In our pursuit of health (the state of being free from illness or injury) we discovered the magic of meditation, the wonderful benefits of prayer, and the infusion of mind, body, and spirit through the consumption of tea. In this pursuit, we have come across various writings, videos, and artistic presentations which can further these efforts. To be of additional service to you, we have compiled an assortment of these works which you may find helpful. Please enjoy as we have.
Bone broth and gelatin have long been used to heal digestive problems, but scientists have recently uncovered the science behind the nutritional power of these foods – the key is collagen! The unique structural properties and amino acid profile of collagen allows this protein to help in reducing gut inflammation, heal stomach ulcers, aid in digestion, and regulate stomach acid secretion. Scientific research has shown collagen synthesis to be an essential biological process in repairing the intestinal lining. Collagen and gut health are related; read below the benefits of supplementing with collagen for leaky gut and other gut conditions.
Collagen Benefits on Gut Health
Collagen Regulates Stomach Acid Secretion
Collagen has been found to regulate the secretion of gastric juices by ensuring enough acid for proper digestion. Collagen protein also prevents an excess of gastric juices, which can lead to heartburn, stomach ulcers, and other painful digestive problems caused from an overly acidic environment1.
Collagen Can Help Heal Stomach Ulcers
Glycine and Proline, the two main amino acids in Further Food Collagen Peptides, can help heal the stomach lining and prevent stress-induced ulcers through their positive impact on the central nervous system. Studies have identified glycine as an effective inhibitor of stomach ulcers due to its ability to prevent harmful gastric secretions in the stomach lining2.
Collagen Aids in Digestion
Another collagen and gut health benefit is that collagen helps digestion. Because collagen is a hydrophilic molecule, it has an attraction to water and acidic molecules, which aids the digestive process. Ingested collagen surrounds itself with water and stomach acid as it moves through the GI tract, which assists the breakdown of other proteins and carbohydrates in the intestines. Additionally, by holding water in the intestine, collagen helps move food through the GI tract more smoothly.
Collagen Helps Repair the Intestinal and Stomach Lining
Want to know how to heal the intestinal and stomach lining? Try supplementing with collagen peptides! Science has identified collagen synthesis as an important component in the process of repairing and healing the intestinal lining. When there is damage or inflammation to the intestinal lining, new smooth muscle cells are made to heal the stomach lining and the intestinal wall. Scientists have found that collagen production in the intestine is greatest when smooth muscle cells are being generated during healing. Thus, collagen is a key component to healing the intestinal wall. Supplementing with collagen can help to repair and heal the stomach lining. 3
Collagen Helps Heal Leaky Gut and IBS
Have you considered supplementing with collagen for leaky gut? Glutamine, one of the amino acids in collagen, has been identified as the key amino acid for preventing inflammation of the gut wall and healing leaky gut syndrome. It has been linked to inhibiting inflammation and oxidative stress associated with the opening of tight junctions in the connective tissue of the intestinal lining4. Studies have found decreased collagen levels in individuals with digestive imbalances. Specifically, there is an association between inflammatory bowel disease and decreased serum collagen levels5. Supplementation with collagen protein is key to providing relief for digestive diseases.
Review of Collagen Benefits for the Gut and Digestion and How to Heal Stomach Lining
– Collagen helps to regulate stomach acid secretion, helping to prevent heartburn, stomach ulcers and other digestive conditions caused by an overly acidic environment
– Further Food Collagen contains two amino acids, glycine and proline, that help heal the stomach lining and prevent stress-induced ulcers
– Collagen helps digestion by holding water in the intestine, helping move food through the GI tract more smoothly
– Collagen is a key component in healing the intestinal wall
– Further Food Collagen contains glutamine which is a key amino acid that prevents inflammation of the gut wall and helps heal leaky gut syndrome
Want to read more?
1. Lin, M. “L-Glutamate Supplementation Improves Small Intestinal Architecture and Enhances the Expressions of Jejunal Mucosa Amino Acid Receptors and Transporters in Weaning Piglets.” National Center for Biotechnology Information. U.S. National Library of Medicine. <http://www.ncbi.nlm.nih.gov/pubmed/25368996>.
2. Tariq, M. Studies on the Antisecretory, Gastric Anti-ulcer and Cytoprotective Properties of Glycine.National Center for Biotechnology Information. U.S. National Library of Medicine, <http://www.ncbi.nlm.nih.gov/pubmed/9344231>.
3. Graham, MF. Collagen Synthesis by Human Intestinal Smooth Muscle Cells in Culture. National Center for Biotechnology Information. U.S. National Library of Medicine. <http://www.ncbi.nlm.nih.gov/pubmed/3792777>.
4. Lin, M. L-Glutamate Supplementation Improves Small Intestinal Architecture and Enhances the Expressions of Jejunal Mucosa Amino Acid Receptors and Transporters in Weaning Piglets.National Center for Biotechnology Information. U.S. National Library of Medicine<http://www.ncbi.nlm.nih.gov/pubmed/25368996>.
5. Koutroubakis, IE. Serum Laminin and Collagen IV in Inflammatory Bowel Disease. National Center for Biotechnology Information. U.S. National Library of Medicine <http://www.ncbi.nlm.nih.gov/pubmed/14600124>.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
The One Food An Inflammation Expert Eats Daily
Chronic inflammation will wreak havoc on your body, both inside and out. The good news is, you can reverse it, and it starts with what you eat. I’m a firm believer in giving my body the absolute best tools to work with, so I eat plenty of organic vegetables, quality proteins, and healthy fats. One of my top priorities is to prevent chronic inflammation, so my diet includes a daily dose of collagen.
Collagen may seem like an unlikely tool in the battle against inflammation, but it’s one of the best ways to keep your body from being in a constant inflammatory state. Collagen’s anti-inflammatory powers come from the role that it plays in our gut health. A healthy gut can reduce inflammation throughout the whole body. The ability of collagen to help restore balance to our digestive tract makes it a major player in the fight against inflammation.
Collagen is one of the most common proteins in the body. In fact, it makes up about a third of the body’s protein content. It’s one of the building blocks of the human body and can help to improve your health, both below and above the surface. It also plays an important role in maintaining skin elasticity, connective tissue flexibility, and even bone strength. Collagen contains glycine, an amino acid with proven anti-inflammatory and immunomodulatory effects.
Sometimes I include the powdered version in a favorite recipe. The rest of the time, I will get it in my daily serving of bone broth. No matter how I choose to ingest it, I make sure to get a dose of collagen every single day. Here are a few of my favorite ways to ensure I’m getting the powerful and healing anti-inflammatory benefits that come from collagen:
1. Bone broth.
Collagen exists in the body in connective tissue, cartilage, and bones. One way to access this wonderful protein is through bone broth. Bone broth is like stock, only it’s cooked for a much longer time. This helps to pull the nutrients and collagen from the bones, cartilage, and joints. It’s a delicious way to reap all the wonderful anti-inflammatory benefits of collagen! I like to call bone broth “liquid gold.” This is because it’s also packed with other nutrients that have the power to transform your body. You can make your own bone broth or you can buy it pre-made. If you opt for the pre-made variety, make sure to buy only organic, grass-fed products. Avoid preservatives, yeast extracts, and any other additives. You’ll also need to watch out for added sugar, as it’s often hidden in pre-made bone broth products. If you grab any bone broth product off the shelf without checking ingredients, you may be doing your body more harm than good. Try having just one cup of bone broth daily, and I promise, you will be begging for more! Here’s an easy chicken bone broth (and even a vegan version!).
Canned fish might seem like a surprising place to find the health-boosting (and face-saving) benefits of collagen, but sardines pack a solid punch on the collagen front since they are packaged with their bones and connective tissue included. Don’t worry, they’re so soft that you won’t even notice them! You can use them as a pizza topping, chop them up finely and put them in salads or soups, or, like many doctors I know, simply eat them with a fork as an on-the-go snack. For an even better flavor, you can even try mixing them with a little avocado mayo or mustard.
Bone broth isn’t the only way to reap collagen’s incredible benefits. It also comes in powdered form, making it easy to include in your daily supplement or meal routine. Usually, when people think of collagen or bone broth, they tend to think “savory.” Of course, that makes sense; after all, chicken broth is the go-to for a soup base. But there’s no need to limit yourself to salty situations! Powdered collagen is flavorless, so you can mix it into your food and beverages in surprising ways. It mixes seamlessly into smoothies, coffees, and plenty of other unsuspecting places! The textural difference is hardly noticeable, and the benefits are out of this world. Supplemental collagen products have come a long way, especially in flavor. They make it easy to take care of our skin and joints while fighting inflammation at the same time.
What if you’re vegan or vegetarian?
If you are a vegetarian or vegan, you can boost your body’s collagen-building power and help protect your existing collagen through the following foods:
- Foods high in vitamin C such as tomatoes, citrus fruits, kiwis, papayas, bell peppers, and broccoli are vital for the synthesis of collagen.
- Dark, leafy greens like spinach and kale contain antioxidants that protect against the free radicals that break down collagen.
- Red veggies like beets as well as fruits like tomatoes and red peppers are full of lycopene, which boosts collagen.
- Orange veggies like carrots and sweet potatoes are loaded with vitamin A, which restores collagen that’s been damaged.
- Foods rich in sulfur such as broccoli, cauliflower, bok choy, cabbage, onions, shallots, and leeks play a key role in collagen production.
- Foods rich in copper such as nuts activate an enzyme that plays a critical role in collagen production.
- White tea helps to shut down the enzymes that break down collagen and another skin protein, elastin.
The bottom line?
Adding collagen into your daily diet is one of the best things you can do to help your body fight inflammation. If you’re just starting to supplement with collagen, make sure to allow enough time for its effects to show up. It may take eight weeks before you notice a reduction in inflammation, visible changes in skin texture, and improvement in joint health. Although that might seem like a long wait, it gives you plenty of time to discover recipes that you love! By simply adding a daily dose of collagen to your diet, you’ll enjoy the gut-healing properties that will reduce inflammation, both inside and out!
Here’s what happens when you drink collagen every day for a month.
He’s known as the pioneer of alternative medicine and has become one of the best-known and wealthiest figures in the field.
Now at 68 years old, Chopra is teaming up with one of Hollywood’s rising stars in health and nutrition, Kimberly Snyder, to transform the way Americans define beauty and wealth.
“Health is the number one trend in the world. And, if you track well-being not just physical, emotional and spiritual, but also what we call social well-being or community well-being, it directly correlates with financial well-being. So, if people ignore their well-being, they are going to have a financial crisis too,” Chopra tells FOXBusiness.com.
Snyder, author of “The Beauty Detox” series and nutritionist to celebrities like Reese Witherspoon, Drew Barrymore, and Kerry Washington, says the idea that inspired the collaboration was redefining beauty from the inside-out.
“Instead of focusing on one specific thing, eating for weight or putting on makeup for the external, our six pillars cover a whole lifestyle that works internally to have you feel and look your most beautiful,” Snyder tells FOXBusiness.com
In their new book, “Radical Beauty,” they outline tips, tools, and guidelines to help people discover the internal issues that are causing their health ailments and lack of fulfillment. The six key pillars of “Radical Beauty” are internal and external nourishment, peak beauty sleep, primal beauty, beautiful movement, and spiritual beauty.
“Your skin actually reflects the quality of your life and what most people are doing is almost like polishing the flower instead of nourishing the root,” adds Chopra.
Part of that nourishment is going back to what’s natural; and that means tossing out the processed foods and chemical-laden cosmetics.
“When I say natural, I mean taking things from your kitchen and moving them over to the bathroom,” says Snyder. “There are things that cost very little but are actually a lot more effective that don’t include those chemicals that get in your system.”
Snyder says it’s not just Hollywood adopting this lifestyle, it’s catching on in the business community as well.
“Studies show that more and more billionaires and successful people are mediating because they are able to settle their mind and make better business decisions and perform at a higher level.”
Chopra adds that taking care of yourself is not only important for your own success, but directly impacts the world around you as well.
“I’m talking about hospital admissions, traffic accidents, and violence, they are all connected to it,” he says. “It’s the most important thing that we can do for our kids and for the future of the world.”
- Phytosterols are plant-derived compounds that are similar in structure and function to cholesterol. (More information)
- Early human diets were rich in phytosterols, providing as much as 1 g/day; however, the typical Western diet today is relatively low in phytosterols. (More information)
- Phytosterols inhibit the intestinal absorption of cholesterol. (More information)
- Numerous clinical trials have demonstrated that daily consumption of foods enriched with at least 0.8 g of plant sterols or stanols lowers serum LDL cholesterol. (More information)
- Although some epidemiological studies have found that higher intakes of plant foods containing phytosterols are associated with decreased cancer risk, it is not clear whether phytosterols or other compounds in plant foods are the protective factors. (More information)
- The results of a few clinical trials suggest that phytosterol supplementation at relatively low doses can improve urinary tract symptoms related to benign prostatic hyperplasia, but further research is needed to confirm these findings. (More information)
- Foods rich in phytosterols include unrefined vegetable oils, whole grains, nuts, and legumes. (More information)
- Foods and beverages with added plant sterols or stanols are now available in many countries throughout the world, and many countries now allow health claims for such commercial products.
Throughout much of human evolution, it is likely that large amounts of plant foods were consumed (1). In addition to being rich in fiber and plant protein, the diets of our ancestors were also rich in phytosterols—plant-derived sterols that are similar in structure and function to cholesterol. There is increasing evidence that the reintroduction of plant foods providing phytosterols into the modern diet can improve serum lipid (cholesterol) profiles and reduce the risk of cardiovascular disease (2).
Although cholesterol is the predominant sterol in animals, including humans, a variety of sterols are found in plants (3). Nutritionists recognize two classes of phytosterols: (1) sterols, which have a double bond in the sterol ring (Figure 1); and (2) stanols, which lack a double bond in the sterol ring (Figure 2). The most abundant sterols in plants and the human diet are sitosterol and campesterol. Stanols are also present in plants, but they comprise only about 10% of total dietary phytosterols. Cholesterol in human blood and tissues is derived from the diet as well as endogenous cholesterol synthesis. In contrast, all phytosterols in human blood and tissues are derived from the diet because humans cannot synthesize phytosterols (4).
Phytosterols: a collective term for plant-derived sterols and stanols.
Plant sterols or stanols: terms generally applied to plant-derived sterols or stanols; these phytochemicals are added to foods or supplements.
Plant sterol or stanol esters: plant sterols or stanols that have been esterified by creating an ester bond between a fatty acid and the sterol or stanol. Esterification occurs in intestinal cells and is also an industrial process. Esterification makes plant sterols and stanols more fat-soluble so they are easily incorporated into fat-containing foods, including margarines and salad dressings. In this article, the weights of plant sterol and stanol esters are expressed as the equivalent weights of free (unesterified) sterols and stanols.
Dietary cholesterol must be incorporated into mixed micelles in order to be absorbed by the cells that line the intestine (enterocytes) (5). Mixed micelles are mixtures of bile salts, lipids (fats), and sterols formed in the small intestine after a fat-containing meal is consumed. Inside the enterocyte, cholesterol is esterified and incorporated into triglyceride-rich lipoproteins known as chylomicrons, which enter the circulation (6). As circulating chylomicrons become depleted of triglycerides, they become chylomicron remnants, which are taken up by the liver. In the liver, cholesterol from chylomicron remnants may be repackaged into other lipoproteins for transport throughout the circulation or, alternatively, secreted into bile, which is released into the small intestine.
Although varied diets typically contain similar amounts of phytosterols and cholesterol, serum phytosterol concentrations are usually several hundred times lower than serum cholesterol concentrations in humans (7). Less than 10% of dietary phytosterols are systemically absorbed, in contrast to about 50-60% of dietary cholesterol (8). Like cholesterol, phytosterols must be incorporated into mixed micelles before they are taken up by enterocytes. Once inside the enterocyte, systemic absorption of phytosterols is inhibited by the activity of efflux transporters, consisting of a pair of ATP-binding cassette (ABC) proteins known as ABCG5 and ABCG8 (4). ABCG5 and ABCG8 each form one half of a transporter that secretes phytosterols and unesterified cholesterol from the enterocyte into the intestinal lumen. Phytosterols are secreted back into the intestine by ABCG5/G8 transporters at a much greater rate than cholesterol, resulting in much lower intestinal absorption of dietary phytosterols than cholesterol. Within the enterocyte, phytosterols are not as readily esterified as cholesterol, so they are incorporated into chylomicrons at much lower concentrations. Those phytosterols that are incorporated into chylomicrons enter the circulation and are taken up by the liver. Once inside the liver, phytosterols are rapidly secreted into bile by hepatic ABCG5/G8 transporters. Although cholesterol may also be secreted into bile, the rate of phytosterol secretion into bile is much greater than cholesterol secretion (9). Thus, the low serum concentrations of phytosterols relative to cholesterol can be explained by decreased intestinal absorption and increased excretion of phytosterols into bile.
It is well-established that high intakes of plant sterols or stanols can lower serum total and LDL cholesterol concentrations in humans (see Cardiovascular disease) (10, 11). In the intestinal lumen, phytosterols displace cholesterol from mixed micelles and inhibit cholesterol absorption (12). In humans, the consumption of 1.5-1.8 g/day of plant sterols or stanols reduced cholesterol absorption by 30-40% (13, 14). At higher doses (2.2 g/day of plant sterols), cholesterol absorption was reduced by 60% (15). In response to decreased cholesterol absorption, tissue LDL-receptor expression was increased, resulting in increased clearance of circulating LDL (16). Decreased cholesterol absorption is also associated with increased cholesterol synthesis, and increasing phytosterol intake has been found to increase endogenous cholesterol synthesis in humans (13). Despite the increase in cholesterol synthesis induced by increasing phytosterol intake, the net result is a reduction in serum LDL cholesterol concentration.
Experiments in cell culture and animal models suggest that phytosterols may have biological activities unrelated to cholesterol lowering. However, their significance in humans is not yet known.
Alterations in cell membrane properties
Cholesterol is an important structural component of mammalian cell membranes (17). Displacement of cholesterol with phytosterols has been found to alter the physical properties of cell membranes in vitro (18), which could potentially affect signal transduction or membrane-bound enzyme activity (19, 20). Limited evidence from an animal model of hemorrhagic stroke suggested that very high intakes of plant sterols or stanols displaced cholesterol in red blood cell membranes, resulting in decreased deformability and potentially increased fragility (21, 22). However, daily phytosterol supplementation (1 g/1,000 kcal) for four weeks did not alter red blood cell fragility in humans (23).
Alterations in testosterone metabolism
Limited evidence from animal studies suggests that very high phytosterol intakes can alter testosterone metabolism by inhibiting 5α-reductase, a membrane-bound enzyme that converts testosterone to dihydrotestosterone, a more potent metabolite (24, 25). It is not known whether phytosterol consumption alters testosterone metabolism in humans. No significant changes in free or total serum testosterone concentrations were observed in men who consumed 1.6 g/day of plant sterol esters for one year (26).
Induction of apoptosis in cancer cells
Unlike normal cells, cancerous cells lose their ability to respond to death signals that initiate apoptosis (programmed cell death). Sitosterol has been found to induce apoptosis when added to cultured human prostate (27), breast (28), and colon cancer cells (29).
Limited data from cell culture and animal studies suggest that phytosterols may attenuate the inflammatory activity of immune cells, including macrophages and neutrophils (30, 31).
Foods enriched with plant sterols or stanols
LDL cholesterol: Numerous clinical trials have found that daily consumption of foods enriched with free or esterified forms of plant sterols or stanols lowers concentrations of serum total and LDL cholesterol (10, 32-35). A meta-analysis that combined the results of 18 controlled clinical trials found that the consumption of spreads providing an average of 2 g/day of plant sterols or stanols lowered serum LDL cholesterol concentrations by 9-14% (36). More recently, a meta-analysis that combined the results of 23 controlled clinical trials found that the consumption of plant foods providing an average of 3.4 g/day of plant sterols or stanols decreased LDL cholesterol concentrations by about 11% (37). Another meta-analysis examined the results of 23 clinical trials of plant sterol-enriched foods and 27 clinical trials of plant stanol-enriched foods, separately (11). At doses of at least 2 g/day, both plant sterols and stanols decreased LDL cholesterol concentrations by about 10%. Doses higher than 2 g/day did not substantially improve the cholesterol-lowering effects of plant sterols or stanols. Most recently, a meta-analysis that analyzed the results of 59 randomized controlled trials found that reductions in LDL cholesterol are greater in those with higher baseline levels of LDL cholesterol (38). The results of studies providing lower doses of plant sterols or stanols suggest that 0.8-1.0 g/day is the lowest dose that results in clinically significant LDL cholesterol reductions of at least 5% (39-43). In general, trials that have compared the cholesterol-lowering efficacy of plant sterols with that of stanols have found them to be equivalent (44-46). Few of these studies lasted longer than four weeks, but at least two studies have found that the cholesterol-lowering effects of plant sterols and stanols last for up to one year (26, 47). In addition to data from controlled clinical trials, a 5-year study that examined the customary use of phytosterol/-stanol enriched margarines under free-living conditions found beneficial effects on cholesterol levels (48). Recently, concerns have been raised that plant sterols are not as effective as stanols in maintaining long-term LDL-cholesterol reductions (49-51). Long-term trials that directly compare the efficacy of plant sterols and plant stanols are needed to address these concerns (11).
Coronary heart disease risk: The effect of long-term use of foods enriched with plant sterols or stanols on coronary heart disease (CHD) risk is not known. The results of numerous intervention trials suggest that a 10% reduction in LDL cholesterol induced by medication or diet modification could decrease the risk of CHD by as much as 20% (52). The National Cholesterol Education Program (NCEP) Adult Treatment Panel III has included the use of plant sterol or stanol esters (2 g/day) as a component of maximal dietary therapy for elevated LDL cholesterol (53). The addition of plant sterol- or stanol-enriched foods to a heart healthy diet that is low in saturated fat and rich in fruit and vegetables, whole grains, and fiber offers the potential for additive effects in CHD risk reduction. For example, following a diet that substituted monounsaturated and polyunsaturated fats for saturated fat resulted in a 9% reduction in serum LDL cholesterol after 30 days, but the addition of 1.7 g/day of plant sterols to the same diet resulted in a 24% reduction (54). More recently, one-month adherence to a diet providing a portfolio of cholesterol-lowering foods, including plant sterols (1 g/1,000 kcal), soy protein, almonds, and viscous fibers lowered serum LDL cholesterol concentrations by an average of 30%—a decrease that was not significantly different from that induced by statin (drugs that inhibit the enzyme, HMG-CoA reductase) therapy (55). However, analysis of individuals on such a cholesterol-lowering diet for one year found that the average LDL cholesterol reduction was only 13%, but almost a third of the participants experienced LDL cholesterol reductions >20% (56). Plant sterols are the major component in this diet responsible for the observed reductions in cholesterol concentrations (57). The US Food and Drug Administration (FDA) has authorized the use of health claims on food labels indicating that regular consumption of foods enriched with plant sterol or stanol esters may reduce the risk of heart disease (58).
Clinical trials finding daily consumption of foods enriched with plant sterols or stanols can significantly lower LDL cholesterol concentrations do not account for naturally occurring phytosterols in the diet (59). Relatively few studies have considered the effects of dietary phytosterol intakes on serum LDL cholesterol concentrations. Dietary phytosterol intakes have been estimated to range from about 150-450 mg/day in various populations (60). Limited evidence suggests that dietary phytosterols may play an important role in decreasing cholesterol absorption. A cross-sectional study in the UK found that dietary phytosterol intakes were inversely related to serum total and LDL cholesterol concentrations even after adjusting for saturated fat and fiber intake (61). Similarly, an analysis in a Swedish population found that dietary intake of phytosterols was inversely associated with total cholesterol in both men and women and with LDL cholesterol in women (62). In single meal tests, removal of 150 mg of phytosterols from corn oil increased cholesterol absorption by 38% (63), and removal of 328 mg of phytosterols from wheat germ increased cholesterol absorption by 43% (64). Although more research is needed, these findings suggest that dietary intakes of phytosterols from plant foods could have an important impact on cardiovascular health.
Limited data from animal studies suggest that very high intakes of phytosterols, particularly sitosterol, may inhibit the growth of breast and prostate cancer (65-67). Only a few epidemiological studies have examined associations between dietary phytosterol intakes and cancer risk in humans because databases providing information on the phytosterol content of commonly consumed foods have only recently been developed. A series of case-control studies in Uruguay found that dietary phytosterol intakes were lower in people diagnosed with stomach, lung, or breast cancer than in cancer-free control groups (68-70). Case-control studies in the US found that women diagnosed with breast or endometrial (uterine) cancer had lower dietary phytosterol intakes than women who did not have cancer (71, 72). In contrast, another case-control study in the US found that men diagnosed with prostate cancer had higher dietary campesterol intakes than men who did not have cancer, but total phytosterol consumption was not associated with prostate cancer risk (73). Although some epidemiological studies have found that higher intakes of plant foods containing phytosterols are associated with decreased cancer risk, it is not clear whether the protective factors are phytosterols or other compounds in plant foods.
Benign prostatic hyperplasia (BPH) is the term used to describe a noncancerous enlargement of the prostate. The enlarged prostate may exert pressure on the urethra, resulting in difficulty urinating. Plant extracts that provide a mixture of phytosterols (marketed as β-sitosterol) are often included in herbal therapies for urinary symptoms related to BPH. However, relatively few controlled studies have examined the efficacy of phytosterol supplements in men with symptomatic BPH. In a six-month study of 200 men with symptomatic BPH, 60 mg/day of a β-sitosterol preparation improved symptom scores, increased peak urinary flow, and decreased post-void residual urine volume compared to placebo (74). A follow-up study reported that these improvements were maintained for up to 18 months in the 38 participants who continued β-sitosterol treatment (75). Similarly, in a six-month study of 177 men with symptomatic BPH, 130 mg/day of a different β-sitosterol preparation improved urinary symptom scores, increased peak urinary flow, and decreased post-void residual urine volume compared to placebo (76). A systematic review that combined the results of these and two other controlled clinical trials found that β-sitosterol extracts increased peak urinary flow by an average of 3.9 ml/second and decreased post-void residual volume by an average of 29 ml (77). Although the results of a few clinical trials suggest that relatively low doses of phytosterols can improve lower urinary tract symptoms related to BPH, further research is needed to confirm these findings (78).
Unlike the typical diet in most developed countries today, the diets of our ancestors were rich in phytosterols, likely providing as much as 1,000 mg/day (1). Present-day dietary phytosterol intakes have been estimated to vary from 150-450 mg/day in different populations (3). Vegetarians, particularly vegans, generally have the highest intakes of dietary phytosterols (79). Phytosterols are found in all plant foods, but the highest concentrations are found in unrefined plant oils, including vegetable, nut, and olive oils (3). Nuts, seeds, whole grains, and legumes are also good dietary sources of phytosterols (5). The phytosterol contents of selected foods are presented in Table 1. For information on the nutrient content of specific foods, search the USDA food composition database.
|Wheat germ||½ cup (57 g)||
|Rice bran oil||1 tablespoon (14 g)||
|Sesame oil||1 tablespoon (14 g)||
|Corn oil||1 tablespoon (14 g)||
|Canola oil||1 tablespoon (14 g)||
|Peanuts||1 ounce (28 g)||
|Wheat bran||½ cup (29 g)||
|Almonds||1 ounce (28 g)||
|Brussels sprouts||½ cup (78 g)||
|Rye bread||2 slices (64 g)||
|Macadamia nuts||1 ounce (28 g)||
|Olive oil||1 tablespoon (14 g)||
|Take Control® spread||1 tablespoon (14 g)||
1,650 mg plant sterol esters
(1,000 mg free sterols)
|Benecol® spread||1 tablespoon (14 g)||
850 mg plant stanol esters
(500 mg free stanols)
The majority of clinical trials that demonstrated a cholesterol-lowering effect used plant sterol or stanol esters solubilized in fat-containing foods, such as margarine or mayonnaise (11). More recent studies indicate that low-fat or even nonfat foods can effectively deliver plant sterols or stanols if they are adequately solubilized (10, 59). Plant sterols or stanols added to low-fat yogurt (43, 84-86), low-fat milk (87-89), low-fat cheese (90), dark chocolate (91), and orange juice (92, 93) have been reported to lower LDL cholesterol in controlled clinical trials. A variety of foods containing added plant sterols or stanols, including margarines, mayonnaises, vegetable oils, salad dressings, yogurt, milk, soy milk, orange juice, snack bars, and meats, are available in the US, Europe, Asia, Australia, and New Zealand (10). A recent meta-analysis found that plant sterols/stanols added to fat spreads, mayonnaise, salad dressings, milk, or yogurt were more effective in reducing LDL cholesterol levels compared to when plant sterols/stanols were incorporated into other products, such as chocolate, orange juice, cheese, meats, and cereal bars (38). Available research indicates that the maximum effective dose for lowering LDL cholesterol is about 2 g/day (11) and the minimum effective dose is 0.8-1.0 g/day (10). In the majority of clinical trials that demonstrated a cholesterol-lowering effect, the daily dose of plant sterols or stanols was divided among two or three meals, which may be more effective in lowering LDL cholesterol (38). However, consumption of the daily dose of plant sterols or stanols with a single meal has been found to lower LDL cholesterol in a few clinical trials (43, 85, 86, 94, 95).
Phytosterol supplements marketed as β-sitosterol are available without a prescription in the US. Doses of 60-130 mg/day of β-sitosterol have been found to alleviate the symptoms of benign prostatic hyperplasia (BPH) in a few clinical trials (see Benign prostatic hyperplasia). Soft gel chews providing 0.5 g of plant stanols are being marketed for cholesterol-lowering at a recommended dose of 2 g/day. Phytosterol supplements should be taken with meals that contain fat.
In the United States, plant sterols and stanols added to a variety of food products are generally recognized as safe (GRAS) by the FDA (96). Additionally, the Scientific Committee on Foods of the EU concluded that plant sterols and stanols added to various food products are safe for human use (97). However, the Committee recommended that intakes of plant sterols and stanols from food products should not exceed 3 g/day because there is no evidence of health benefits at higher intakes and there might be undesirable effects at high intakes.
Few adverse effects have been associated with regular consumption of plant sterols or stanols for up to one year. People who consumed a plant sterol-enriched spread providing 1.6 g/day did not report any more adverse effects than those consuming a control spread for up to one year (26), and people consuming a plant stanol-enriched spread providing 1.8-2.6 g/day for one year did not report any adverse effects (47). Consumption of up to 8.6 g/day of phytosterols in margarine for three to four weeks was well-tolerated by healthy men and women and did not adversely affect intestinal bacteria or female hormone levels (98). Although phytosterols are usually well-tolerated, nausea, indigestion, diarrhea, and constipation have occasionally been reported (74, 76).
Sitosterolemia, also known as phytosterolemia, is a very rare hereditary disease that results from inheriting a mutation in both copies of the ABCG5 or ABCG8 gene (99). Individuals who are homozygous for a mutation in either transporter protein have dramatically elevated serum phytosterol concentrations due to increased intestinal absorption and decreased biliary excretion of phytosterols. Although serum cholesterol concentrations may be normal or only mildly elevated, individuals with sitosterolemia are at high risk for premature atherosclerosis. People with sitosterolemia should avoid foods or supplements with added plant sterols (10). Two studies have examined the effect of plant sterol consumption in heterozygous carriers of sitosterolemia, a more common condition. Consumption of 3 g/day of plant sterols for four weeks by two heterozygous carriers (100) and consumption of 2.2 g/day of plant sterols for 6-12 weeks by 12 heterozygous carriers did not result in abnormally elevated serum phytosterols (101).
Plant sterols or stanols added to foods or supplements are not recommended for pregnant or breast-feeding women because their safety has not been studied (10). At present, there is no evidence that high dietary intakes of naturally occurring phytosterols, such as those consumed by vegetarian women, adversely affects pregnancy or lactation.
The LDL cholesterol-lowering effects of plant sterols or stanols may be additive to those of HMG-CoA reductase inhibitors (statins) (102, 103). The results of controlled clinical trials suggest that consumption of 2-3 g/day of plant sterols or stanols by individuals on statin therapy may result in an additional 7-11% reduction in LDL cholesterol, an effect comparable to doubling the statin dose (50, 104-106). Consumption of 4.5 g/day of stanol esters for eight weeks did not affect prothrombin times (INR) in patients on warfarin (Coumadin) for anticoagulation (107).
Fat-soluble vitamins (vitamins A, D, E, and K)
Because plant sterols and stanols decrease cholesterol absorption and serum LDL cholesterol concentrations, their effects on fat-soluble vitamin status have also been studied in clinical trials. Plasma vitamin A (retinol) concentrations were not affected by plant stanol or sterol ester consumption for up to one year (11, 26). Although the majority of studies found no changes in plasma vitamin D (25-hydroxyvitamin D3) concentrations, one placebo-controlled study in individuals consuming 1.6 g/day of sterol esters for one year observed a small (7%) but statistically significant decrease in plasma 25-hydroxyvitamin D3 concentrations (26). There is little evidence that plant sterol or stanol consumption adversely affects vitamin K status. Consumption of 1.6 g/day of sterol esters for six months was associated with a nonsignificant 14% decrease in plasma vitamin K1 concentrations, but carboxylated osteocalcin, a functional indicator of vitamin K status, was unaffected (26). In other studies of shorter duration, consumption of plant sterol and stanol esters did not significantly change plasma concentrations of vitamin K1 (108, 109) or vitamin K-dependent clotting factors (110). Consumption of plant sterol or stanol-enriched foods has been found to decrease plasma vitamin E (α-tocopherol) concentrations in a number of studies (11, 109). However, those decreases generally do not persist when plasma α-tocopherol concentrations are standardized to LDL cholesterol concentrations. This suggests that observed reductions in plasma α-tocopherol are due in part to reductions in its carrier lipoprotein, LDL. In general, consumption of plant sterol- and stanol-enriched foods at doses of 1.5 g/day or more have not been found to have adverse effects on fat-soluble vitamin status in well-nourished populations.
Dietary carotenoids are fat-soluble phytochemicals that circulate in lipoproteins. A number of studies have observed 10-20% reductions in plasma carotenoids after short-term and long-term consumption of plant sterol- or stanol-enriched foods (11). Even when standardized to serum total or LDL cholesterol concentrations, decreases in α-carotene, β-carotene, and lycopene may persist, suggesting that phytosterols can inhibit the absorption of these carotenoids (111). It is not clear whether reductions in plasma carotenoid concentrations confer any health risks, but several studies have found that increasing intakes of carotenoid-rich fruit and vegetables can prevent phytosterol-induced decreases in plasma carotenoids (112). In one case, advice to consume five daily servings of fruit and vegetables, including one serving of carotenoid-rich vegetables, was enough to maintain plasma carotenoid levels in people consuming 2.5 g/day of plant sterol or stanol esters (113).
Originally written in 2005 by:
Jane Higdon, Ph.D.
Linus Pauling Institute
Oregon State University
Updated in September 2008 by:
Victoria J. Drake, Ph.D.
Linus Pauling Institute
Oregon State University
Reviewed in September 2008 by:
Peter J.H. Jones, Ph.D.
Professor of Nutrition
Director, Mary Emily Clinical Nutrition Research Center
School of Dietetics and Human Nutrition
Copyright 2005-2016 Linus Pauling Institute
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By now, everyone’s heard about the life-extending benefits of caloric restriction. Lab results show that drastically cutting food intake can nearly double longevity in rodents, worms, and flies, and a massive 20-year study on rhesus monkeys, a species closely related to humans, found that the benefits of the diet seem to be universal: a resistance to cancer, heart disease, and age-related cognitive decline.
There’s even a Calorie Restriction Society International, with thousands of members who live off roughly 30 percent fewer calories than the number recommended by conventional medicine. The downside, of course – and it’s a big one – is, who wants to live a life of deprivation? But what if there were a shortcut? What if you could get the benefits of calorie restriction without the same degree of sacrifice? Many people now believe you can. The idea is called intermittent fasting (IF), and it’s becoming the diet du jour of weightlifters, crossfitters, and the paleo set.
“When people hear the term fasting, they tend to think of a week of not eating,” says Brad Pilon, author of the book ‘Eat Stop Eat.’ “Instead, I like to think of it as taking a break from eating.”
IF is not what most people typically think of as fasting – going without food or sustenance for days. Instead, IFers believe you can reap all the benefits (and more) of chronic calorie restriction after as few as 12 hours without food. Which means that simply skipping breakfast and waiting until lunch to eat any food (most say it’s OK to put a splash of cream in your coffee) counts as IF.
It seems counterintuitive, but skipping meals helps you feel more energized, recover better from exercise, blast fat, and retain lean muscle mass, and even protects your body from heart disease, cancer, diabetes, and cognitive decline – which is why NASA is interested in looking at fasting to improve the cognitive functioning of pilots and unmanned-aerial-vehicle operators.
How does skipping meals provide these types of benefits? Because we were once hunters and gatherers who sometimes went days between meals, our bodies were designed to survive in times of feast and famine. Most Americans now live off a constant drip of processed food, which keeps blood sugars elevated and immune systems depressed.
Breaking off this continual drip of refined, high-sugar, high-carbohydrate food isn’t as tricky as it might seem, say proponents of IF, who swear the diet’s protocol is simple and easy to follow. “Once you get through the first couple of weeks, it’s easy,” says John Olson, former director of the Strategic Analysis and Integration Division in Human Exploration and Operations at NASA. “If you have a healthy diet going into it, it’s not really that big of a deal,” he adds. “If you have a junk diet, it’s going to be hard. For me, it’s been transformational. I would say, anecdotally, the cognitive improvements are noticeable almost immediately.”
Weight loss and fitness gains
We learned in high school biology that the body’s fuel source is glucose – blood sugar. We get it in abundance by eating sugar and refined carbohydrates like bread, pasta, and sports drinks. But our body can burn another type of fuel known as ketones. These molecules are created when your body runs out of glucose and starts to burn fat, which happens when you fast. Your system switches fuel sources from sugar to fat without breaking down muscle.
If you exercise during your fasted state, you can supercharge your body’s fat-burning potential. Studies show that growth hormone, which has serious muscle-building properties, surges during fasts. The spike of this muscle-molding hormone proves that fasting is not simply about calories in and calories out. The human body appears to have adapted to thrive during short bouts of going without food.
That’s not to say, though, that you should attempt a marathon during a fast. Most people do a short stretch – around 45 minutes – of moderate exercise like strength training or bike riding that can run through their blood glucose and turbocharge ketosis. “My clients find fasting not only increases fat burning, but they feel better and feel stronger as they get used to it,” says Jon Haas, owner of functional fitness gym Warrior Fitness in Hainesport, New Jersey. Proponents also say the notion of not having to eat three square meals a day is freeing and makes you feel more in control of your body. “It provides another level of mental toughness,” says Haas. “This is how your body was designed to function.”
The downside of IF is that research shows people who fast are much more likely to reach for high-calorie, carbohydrate-rich foods when they eat again. These foods were never a problem, evolutionarily speaking, until the advent of soda, hoagies, and all-you-can-eat pasta buffets. Still, the research makes sense: If you haven’t eaten in 20 hours, why wouldn’t your body go for the biggest bang for the caloric buck? But IFers go a step further and claim the science behind bingeing after a fast is faulty. “To my knowledge,” says Mark Sisson, author of ‘The Primal Blueprint‘ and a proponent of IF, “these studies are not done on people adjusted to burning fat, so it’s not surprising that someone on a moderate- to high-carbohydrate diet is going to go for the carbs when they start eating again – the brain of a sugar burner is always expecting sugar.” Sisson’s comments mirror the reports of the legions of people who claim there’s an adaptation period as the body becomes more efficient at converting fat into ketones – or, as Sisson calls it, “becoming a fat-burning beast.”
An extensive body of research conducted by institutions like the University of California at Berkeley, the University of Southern California, and Chicago’s Mount Sinai now shows that IF may help prevent and treat cancer. During a fast, the cells in our bodies go into a protective mode, while cancerous cells continue their metastatic, robotic growth. But the fasted state is hostile to cancer cells in part because their fuel – glucose – disappears from the bloodstream. The same is true of precancerous cells – the type that lead to cancer – says Valter Longo, director of the University of Southern California Longevity Institute. “Imagine someone who has precancerous cells,” says Longo. “The process of developing cancer could take years, but if that person fasted, those cells could be killed before they had a chance to spread.” Longo, who has shown that the act of fasting itself can kill cancer cells, is now working with the Dr. Otto Buchinger Clinic in Germany, an institute that has promoted therapeutic fasting for almost a century, to develop more human studies to better understand why IF may be beneficial for treating and preventing cancer.
Longevity and neuroprotection
Fasting challenges your brain in a way that’s similar to exercising muscle, says Mark Mattson, of the National Institute on Aging. “When the brain goes under energy restriction, we see neural activity that’s associated with protection against degeneration from stroke and aging,” says Mattson. “Fasting increases BDNF, a protein that’s crucial for learning and protection against age-related cognitive decline.” There’s also evidence that ketone bodies converted from fat and used as fuel during fasting may protect against neurodegenerative diseases like epilepsy, moderate autism, and Alzheimer’s.
Master the fast
When Brad Pilon, a major guru of the IF diet, dropped out of his job in the supplement industry to attend graduate school, his goal was to create the ultimate diet. He was astonished to learn the key to longevity was to regularly skip eating. He developed what’s since become the main reference title of IF followers: ‘Eat Stop Eat’. It’s updated annually, and it recommends two 24-hour fasts a week. But it’s by no means the only protocol in the world of fasting. While most IF adherents have their own method for restricting food, the most popular seems to be skipping breakfast, which allows you to include sleep in your fasting cycle. If you eat dinner by 9 p.m., for example, all you need to do is skip breakfast and then resume eating at 1 pm for a solid 16-hour fast, or push it longer. “Fat loss starts happening at about 12 to 13 hours and plateaus around 18 hours,” says Pilon, who also has a master’s in human biology and nutritional science from the University of Guelph in Ontario.
Though we’ve been told for years to fuel up before working out, IF loyalists report that doing strength training midfast provides them with more energy than they would have had if they’d eaten breakfast. It does take some getting used to, however. You’re essentially switching fuel sources from glucose to ketone molecules, and your body becomes more efficient at doing so over time – something IF advocates call being keto-adapted. It’s like tapping into a tank of different fuel, and people report having greater concentration while burning ketones. As with so many things in the health sphere these days, what’s old seems to be what’s new. Many of the world’s great religions call for fasting regimens; Socrates was a fanatical proponent; and Benjamin Franklin may have said it best: “To lengthen thy life, lessen thy meals.”
Despite the most widely accepted and well-established chronic disease practice guidelines uniformly calling for lifestyle change as the first line of therapy, doctors often don’t follow these recommendations. As seen in my video below, lifestyle interventions are not only safer and cheaper but often more effective in reducing heart disease and failure, hypertension, stroke, cancer, diabetes and deaths from all causes than nearly any other medical intervention.
“Some useful lessons may come from the war on tobacco,” Dr. Neal Barnard wrote in the American Medical Association’s ethics journal. When he stopped smoking himself in the 1980s, the lung cancer death rate was peaking in the United States. As the prevalence of smoking dropped, so have lung cancer rates. No longer were doctors telling patients to “[g]ive your throat a vacation” by smoking a fresh cigarette. Doctors realized they were “more effective at counseling patients to quit smoking if they no longer had tobacco stains on their own fingers.” “In other words, doctors went from being bystanders—or even enablers—to leading the fight against smoking.” And today, says Dr. Barnard, “Plant-based diets are the nutritional equivalent of quitting smoking.”
From an editorial in the journal Alternative Therapies in Health and Medicine: “If we were to gather the world’s top nutrition scientists and experts (free from food industry influence), there would be very little debate about the essential properties of good nutrition. Unfortunately, most doctors are nutritionally illiterate. And worse, they don’t know how to use the most powerful medicine available to them: food.”
Physician advice matters. When doctors told patients to improve their diets by cutting down on meat, dairy, and fried foods, patients were more likely to make dietary changes. It may work even better if doctors practice what they preach. Researchers at Emory University randomized patients to watch one of two videos. In one video, a physician briefly mentioned her personal dietary and exercise practices and visible on her desk were both a bike helmet and an apple. In the other video, she did not discuss her personal healthy practices, and the helmet and apple were missing. In both videos, the doctor advised the patients to cut down on meat, not usually have meat for breakfast, and have no meats for lunch or dinner at least half the time. In the disclosure video, the physician related that she herself had successfully cut down on meat. Perhaps not surprisingly, patients rated that physician to be more believable and motivating. Physicians who walk the walk—literally—and have healthier eating habits not only tend to counsel more about exercise and diet, but have been found to seem more credible or motivating when they do so.
It may also make them better doctors. A randomized controlled intervention to clean up doctors’ diets, called the Promoting Health by Self Experience (PHASE) trial, found that healthcare providers’ personal lifestyles were correlated directly with their clinical performance. Healthcare providers’ improved wellbeing and lifestyle cascaded to the patients and clinics, suggesting an additional strategy to achieve successful health promotion.
Are you ready for the best kept secret in medicine? Given the right conditions, the body can heal itself. For example, treating cardiovascular disease with appropriate dietary changes is good medicine, reducing mortality without any adverse effects. We should keep doing research, certainly, but educating physicians and patients alike about the existing knowledge regarding the power of nutrition as medicine may be the best investment we can make.
Michael Greger, M.D.
PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations—2013: Uprooting the Leading Causes of Death, More Than an Apple a Day, 2014: From Table to Able: Combating Disabling Diseases with Food, 2015: Food as Medicine: Preventing and Treating the Most Dreaded Diseases with Diet, and my latest, 2016: How Not To Die: The Role of Diet in Preventing, Arresting, and Reversing Our Top 15 Killers.
In the first evidence of a natural intervention triggering stem cell-based regeneration of an organ or system, a study in the June 5 issue of the Cell Stem Cell shows that cycles of prolonged fasting not only protect against immune system damage — a major side effect of chemotherapy — but also induce immune system regeneration, shifting stem cells from a dormant state to a state of self-renewal.
In both mice and a Phase 1 human clinical trial involving patients receiving chemotherapy, long periods of not eating significantly lowered white blood cell counts. In mice, fasting cycles then “flipped a regenerative switch,” changing the signaling pathways for hematopoietic stem cells, which are responsible for the generation of blood and immune systems, the research showed.
We could not predict that prolonged fasting would have such a remarkable effect in promoting stem cell-based regeneration of the hematopoietic system.
The study has major implications for healthier aging, in which immune system decline contributes to increased susceptibility to disease as people age. By outlining how prolonged fasting cycles — periods of no food for two to four days at a time over the course of six months — kill older and damaged immune cells and generate new ones, the research also has implications for chemotherapy tolerance and for those with a wide range of immune system deficiencies, including autoimmunity disorders.
“We could not predict that prolonged fasting would have such a remarkable effect in promoting stem cell-based regeneration of the hematopoietic system,” said corresponding author Valter Longo, Edna M. Jones Professor of Gerontology and the Biological Sciences at the USC Davis School of Gerontology and director of the USC Longevity Institute. Longo has a joint appointment at the USC Dornsife College of Letters, Arts and Sciences.
“When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged,” Longo said. “What we started noticing in both our human work and animal work is that the white blood cell count goes down with prolonged fasting. Then when you re-feed, the blood cells come back. So we started thinking, well, where does it come from?”
Prolonged fasting forces the body to use stores of glucose, fat and ketones, but it also breaks down a significant portion of white blood cells. Longo likens the effect to lightening a plane of excess cargo.
During each cycle of fasting, this depletion of white blood cells induces changes that trigger stem cell-based regeneration of new immune system cells. In particular, prolonged fasting reduced the enzyme PKA, an effect previously discovered by the Longo team to extend longevity in simple organisms and which has been linked in other research to the regulation of stem cell self-renewal and pluripotency — that is, the potential for one cell to develop into many different cell types. Prolonged fasting also lowered levels of IGF-1, a growth-factor hormone that Longo and others have linked to aging, tumor progression and cancer risk.
“PKA is the key gene that needs to shut down in order for these stem cells to switch into regenerative mode. It gives the OK for stem cells to go ahead and begin proliferating and rebuild the entire system,” explained Longo, noting the potential of clinical applications that mimic the effects of prolonged fasting to rejuvenate the immune system. “And the good news is that the body got rid of the parts of the system that might be damaged or old, the inefficient parts, during the fasting. Now, if you start with a system heavily damaged by chemotherapy or aging, fasting cycles can generate, literally, a new immune system.”
Prolonged fasting also protected against toxicity in a pilot clinical trial in which a small group of patients fasted for a 72-hour period prior to chemotherapy, extending Longo’s influential past research.
“While chemotherapy saves lives, it causes significant collateral damage to the immune system. The results of this study suggest that fasting may mitigate some of the harmful effects of chemotherapy,” said co-author Tanya Dorff, assistant professor of clinical medicine at the USC Norris Comprehensive Cancer Center and Hospital. “More clinical studies are needed, and any such dietary intervention should be undertaken only under the guidance of a physician.”
“We are investigating the possibility that these effects are applicable to many different systems and organs, not just the immune system,” said Longo, whose lab is in the process of conducting further research on controlled dietary interventions and stem cell regeneration in both animal and clinical studies.
The study was supported by the National Institute of Aging of the National Institutes of Health (grant numbers AG20642, AG025135, P01AG34906). The clinical trial was supported by the V Foundation and the National Cancer Institute of the National Institutes of Health (P30CA014089).
Chia Wei-Cheng of USC Davis was first author of the study. Gregor Adams, Xiaoying Zhou and Ben Lam of the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC; Laura Perin and Stefano Da Sacco of the Saban Research Institute at Children’s Hospital Los Angeles; Min Wei of USC Davis; Mario Mirisola of the University of Palermo; Dorff and David Quinn of the Keck School of Medicine of USC; and John Kopchick of Ohio University were co-authors of the study.
Eastern nutrition and diet recommendations
- Eat in season, local grown food and a wholesome diet at least 90% of the time.
- Eat according to your constitution: if you’re from an Asian background, you probably won’t do well on dairy because it’s not part of that continent’s diet. If you’re from a Scandinavian background, you probably won’t do well with very spicy foods, as again it isn’t part of the northern Europe’s diet.
- Eat according to where you are in your life and adapt to changes. If you’re a menopausal woman and are hot all the time, even though, you used to be cold most of your life, it’s time to adapt and avoid warming foods such as hot spices, alcohol or lamb. If you have a constant stuffy nose and allergies in the spring, you need to avoid mucus forming foods such as dairy, wheat, sugar and beer.
- For a complete diet assessment: talk to your acupuncturist.
The 5 flavors of foods and their influence on our health
It is important to have a balance diet with all flavors. If a person has not reached optimum health, then some foods with certain flavors may help restore a healthy body and mind. Here are the 5 flavors and their healing properties, as well as their cautions. Now you can incorporate more or less of these foods depending on your health and condition.
Cooling, contracting, astringent, prevent fluid leakage, dry & firm tissues
Season: Best used in Fall
Sour & Bitter: Vinegar
Sour & pungent: Leek
Sour & Sweet
Cooling, descending, clears & reduces, lower fever, dry fluid, drain dampness, induce bowel movement
Season: Best used in winter, at any time if heat symptoms
Bitter & Pungent
Bitter & Sweet
Ascending, goes outward, harmonizing, slowing, relaxing, build fluids tonifying thin-dry weak people.
Season: Best used in between seasons but may be used in all seasons
Sweet & Sour
Sweet & Bitter
Sweet & Pungent
Disperse, expand, stimulate circulation, ascending & outward direction
Season: Best used in the spring
Cooling, descending, moistens, soften hard lumps, reduce stiffness, detoxify, purge bowel
Season: Best used in the Fall & winter
Salty & sweet