Anti-aging made easy

Anti-aging diets have been around since the 15th century, starting with the books written by Luigi Cornaro. Although I addressed the history of Luigi in my book The Anti-Aging Zone written more than a decade ago, it bears repeating. Finding himself near death at age 35, Luigi Cornaro went on a strict calorie-restricted diet consisting primarily of an egg yolk, some vegetable soup, small amounts of locally grown fruits and vegetables, a very small amount of coarse, unrefined bread and about three glasses of red wine per day. He wrote his first anti-aging book (The Sure and Certain Method of Attaining a Long and Healthful Life) at age 83 and his third book at age 95. He finally died at age 99. At the end of his life he was still mentally sharp and physically active.

Isn’t that what anti-aging is supposed to be? Living a long and full life. But do you have to embark on such a restrictive diet? Can’t you just take a pill or alter a gene? In the Aug. 29th issue of Cell Reports, there is an article that suggests it might be possible to alter such a gene (1). The gene in question mTOR expresses two proteins mTORC1 and mTORC2. mTOR is shorthand for “mammalian target of rapamycin”. Rapamycin is an antibiotic isolated from the soil of Easter Island and is also a powerful immune suppressor. It has been demonstrated that the earlier you give rapamycin to mice, the more you slow their aging process (2,3). In this study researchers genetically reduced the activity of mTOR gene by 75% so it was like giving rapamycin at birth. As might be expected, there was an even greater increase in overall lifespan of the mice corresponding to adding another 16 years of life to humans. These genetically altered mice also appeared to maintain their cognitive skills to a greater extent than the controls, but on the down side they also had less muscle mass and bone density. More ominously, the genetically altered mice also appeared to be more susceptible to infections in old age, suggesting that their immune systems were compromised.

OK so you get some tradeoffs by inhibiting mTOR gene expression: A longer life with greater frailty and decreased immune function as you age. Obviously, you don’t want anyone tinkering with your genes because no one knows the outcome. However, you can tweak gene expression using diet.

One way to reduce mTOR activity is to simply reduce the levels of the amino acid leucine in your diet. This is because leucine stimulates mTOR. If you stimulate mTOR, then you build bigger and stronger muscles. That’s why body builders use a lot isolated dairy protein powders that are rich in leucine as well as eat a lot of egg whites (an even richer source of leucine). On the other hand, vegans don’t eat dairy or eggs and therefore get very little dietary leucine, and their lack of muscles show it. Unfortunately, one of the biggest problems with aging is lack of muscle mass and a less than optimal immune system. So just turning down mTOR activity is probably not sufficient for healthy aging. On the other hand, calorie restriction (like that of Luigi Cornaro) stimulates another gene known as SIRT1 that causes the increased expression of the “enzyme of life” (AMP kinase) that controls metabolism and slows the aging process. You can also stimulate SIRT1 by consuming lots of polyphenols. Can’t you just fine-tune both mTOR and AMP kinase and maximize your quality of life as you age?

Of course you can by having a dietary program consisting of consuming small (but not excessive) amounts of leucine in the blood throughout the day. You can do this by eating no more high-quality protein than you can fit on the palm of your hand. This is about 3 ounces for women and 4 ounces for men. This will activate the mTOR that is necessary to build and maintain muscle and bone. By consuming large amounts of non-starchy vegetables, you are consuming polyphenols that stimulate AMP kinase. By doing both, you are constantly balancing mTOR and AMP kinase but without the rigid calorie restriction undertaken by Luigi Cornaro nearly 500 years ago. You are still restricting calories, but now in the range of 1,200 to 1,500 calories per day compared to the estimated 600 calories per day that Luigi was consuming.

Just to cover your bets since you would be consuming more leucine than Luigi did, you need to counter balance that with more polyphenols most likely by supplementation. Consuming one to two glasses of red wine per day is one way to get extra polyphenols. A better way is to use purified extracts rich in polyphenols, but without the alcohol. Finally for good measure, you want to take at least 2.5 grams of EPA and DHA as that level has been shown to increase the levels of telomeres that further decrease the rate of aging (4).

But isn’t that the Zone Diet? Of course it is, and that’s why I wrote The Anti-Aging Zone more than a decade ago. It was true then, and it is still true today.

References

  1. Wu JJ, Chen EB, Wang JJ, Cao L, Narayan N, Fergusson MM, Rovira II, Allen M, Springer DA, Lago CU, Zhang S, DuBois W, Ward T, deCabo R, Garilova O, Mock B, and Finkel T. “Increased mammalian lifespan and a segmental and tissue-specific slowing of aging after genetic reduction of mTOR expression.” Cell Reports 4:1-8 (2013)
  2. Harrison DE, Strong R, Sharp ZD, Nelson JF, Astle CM, Flurkey K, Nadon NL, Wilkinson JE, Frenkel K, Carter CS, Pahor M, Javors MA,Fernandez E, and Miller RA. “Rapamycin fed late in life extends lifespan in genetically heterogeneous mice.” Nature 460: 395-395 (2009)
  3. Miller RA, Harrison DE, Astle CM, Baur JA, Boyd AR, de Cabo R; Fernandez E, Flurkey K, Javors MA, Nelson JF, Orihuela CJ, Pletcher S, Sharp ZD, Sinclair D, Starnes JW, Wilkinson JE, Nadon NL, and Strong R. “Rapamycin, but not resveratrol or simvastatin, extends life span of genetically heterogeneous mice.” J Gerontol A Biol Sci Med Sci 66:191-201 (2011)
  4. Kiecolt-Glaser JK. Epel ES. Belury MA. Andridge R, Lin J, Glaser R, Malarkey WB, Hwang BS, and Blackburn E. “Omega-3 fatty acids, oxidative stress, and leukocyte telomere length: A randomized controlled trial.” Brain Behav Immun 28:16-24 (2013)

What is Cellular Inflammation?

People (including virtually all physicians) are constantly confused what cellular inflammation is. So I decided to take the opportunity to explain the concept in more detail.

There are two types of inflammation. The first type is classical inflammation, which generates the inflammatory response we associate with pain such as, heat, redness, swelling, pain, and eventually loss of organ function. The other type is cellular inflammation, which is below the perception of pain. Cellular inflammation is the initiating cause of chronic disease because it disrupts hormonal signaling networks throughout the body.

Definition of Cellular Inflammation

The definition of cellular inflammation is increased activity of the gene transcription factor know as Nuclear Factor-kappaB (NF-κB). This is the gene transcription factor found in every cell, and it activates the inflammatory response of the innate immune system. Although the innate immune system is the most primitive part of our immune response, it has been resistant to study without recent breakthroughs in molecular biology. In fact, the 2011 Nobel Prize in Medicine was awarded for the earliest studies on the innate immune system and its implications in the development of chronic disease.

There are several extracellular events through which NF-κB can be activated by distinct mechanisms. These include microbial invasion recognized by toll-like receptors (TLR), generation of reactive oxygen species (ROS), cellular generation of inflammatory eicosanoids, and interaction with inflammatory cytokines via defined cell surface receptors. We also know that several of these initiating events are modulated by dietary factors. This also means that appropriate use of the diet can either turn on or turn off the activation of NF-κB. This new knowledge is the foundation of anti-inflammatory nutrition (1-3).

Understanding Cellular Inflammation

Although the innate immune system is exceptionally complex, it can be illustrated in a relatively simple diagram as shown below in Figure 1.

Figure 1. Simplified View of the Innate Immune System

Essential fatty acids are the most powerful modulators of NF-κB. In particular, the omega-6 fatty acid arachidonic acid (AA) activates NF-κB, whereas the omega-3 fatty acid eicosapentaenoic acid (EPA) does not (4). Recent work suggests that a subgroup of eicosanoids known as leukotrienes that are derived from AA may play a significant factor in NF-κB activation (5,6)

Extracellular inflammatory cytokines can also activate NF-κB by their interaction with specific receptors on the cell surface. The primary cytokine that activates NF-κB is tumor necrosis factor (TNF) (7). Toll-like receptors (TLR) are another starting point for the activation of NF-κB. In particular, TLR-4 is sensitive to dietary saturated fatty acids (8). The binding of saturated fatty acids to TLR-4 can be inhibited by omega-3 fatty acids such as EPA. Finally ROS either induced by ionizing radiation or by excess free radical formation are additional activators of NF-κB (9).

Anti-inflammatory Nutrition To Inhibit Cellular Inflammation

Anti-inflammatory nutrition is based on the ability of certain nutrients to reduce the activation of NF-κB.

The most effective way to lower the activation of NF-κB is to reduce the levels of AA in the target cell membrane thus reducing the formation of leukotrienes that can activate NF-κB. Having the patient follow an anti-inflammatory diet, such as the Zone Diet coupled with the simultaneous lowering omega-6 fatty acid intake are the primary dietary strategies to accomplish this goal (1-3).

Another effective dietary approach (and often easier for the patient to comply with) is the dietary supplementation with adequate levels of high-dose fish oil rich in omega-3 fatty acids, such as EPA and DHA. These omega-3 fatty acids taken at high enough levels will lower AA levels and increase EPA levels. This change of the AA/EPA ratio in the cell membrane will reduce the likelihood of the formation of inflammatory leukotrienes that can activate NF-κB. This is because leukotrienes derived from AA are pro-inflammatory, whereas those from EPA are non-inflammatory. The increased intake of omega-3 fatty acids is also a dietary approach that can activate the anti-inflammatory gene transcription factor PPAR-γ (10-12), decrease the formation of ROS (13) and decrease the binding of saturated fatty acids to TLR-4 (14). This illustrates the multi-functional roles that omega-3 fatty acids have in controlling cellular inflammation.

A third dietary approach is the adequate intake of dietary polyphenols. These are compounds that give fruits and vegetables their color. At high levels they are powerful anti-oxidants to reduce the generation of ROS (15). They can also inhibit the activation of NF-κB (16).

Finally, the least effective dietary strategy (but still useful) is the reduction of dietary saturated fat intake. This is because saturated fatty acids will cause the activation of the TLR-4 receptor in the cell membrane (8,14).

Obviously, the greater the number of these dietary strategies implemented by the patient, the greater the overall effect on reducing cellular inflammation.

Clinical Measurement of Cellular Inflammation

Since cellular inflammation is confined to the cell itself, there are few blood markers that can be used to directly measure the levels of systemic cellular inflammation in a cell. However, the AA/EPA ratio in the blood appears to be a precise and reproducible marker of the levels of the same ratio of these essential fatty acids in the cell membrane.

As described above, the leukotrienes derived from AA are powerful modulators of NF-κB. Thus a reduction in the AA/EPA ratio in the target cell membrane will lead to a reduced activation of NF-κB by decreased formation of inflammatory leukotrienes. The cell membrane is constantly being supplied by AA and EPA from the blood. Therefore the AA/EPA ratio in the blood becomes an excellent marker of the same ratio in the cell membrane (17). Currently the best and most reproducible marker of cellular inflammation is the AA/EPA ratio in the blood as it represents an upstream control point for the control of NF-κB activation.

The most commonly used diagnostic marker of inflammation is C-reactive protein (CRP). Unlike the AA/EPA ratio, CRP is a very distant downstream marker of past NF-κB activation. This is because one of inflammatory mediators expressed in the target cell is IL-6. It must eventually reach a high enough level in the blood to eventually interact with the liver or the fat cells to produce CRP. This makes CRP a more long-lived marker in the blood stream compared to the primary inflammatory gene products (IL-1, IL-6, TNF, and COX-2) released after the activation of NF-κB. As a consequence, CRP is easier to measure than the most immediate inflammatory products generated by NF-κB activation. However, easier doesn’t necessarily translate into better. In fact, an increase AA/EPA ratio in the target cell membrane often precedes any increase of C-reactive protein by several years. An elevated AA/EPA ratio indicates that NF-κB is at the tipping point and the cell is primed for increased genetic expression of a wide variety of inflammatory mediators. The measurement of CRP indicates that NF-κB has been activated for a considerable period of time and that cellular inflammation is now causing systemic damage.

Summary

I believe the future of medicine lies in the control of cellular inflammation. This is most effectively accomplished by the constant application of anti-inflammatory nutrition. The success of such dietary interventions can be measured clinically by the reduction of the AA/EPA ratio in the blood.

References

  1. Sears B. The Anti-Inflammation Zone. Regan Books. New York, NY (2005)
  2. Sears B. Toxic Fat. Thomas Nelson. Nashville, TN (2008)
  3. Sears B and Riccordi C. “Anti-inflammatory nutrition as a pharmacological approach to treat obesity.” J Obesity doi:10.1155/2011/431985 (2011)
  4. Camandola S, Leonarduzzi G,Musso T, Varesio L, Carini R, Scavazza A, Chiarpotto E, Baeuerle PA, and Poli G. “Nuclear factor kB is activated by arachidonic acid but not by eicosapentaenoic acid.” Biochem Biophys Res Commun 229:643-647 (1996)
  5. Sears DD, Miles PD, Chapman J, Ofrecio JM, Almazan F, Thapar D, and Miller YI. “12/15-lipoxygenase is required for the early onset of high fat diet-induced adipose tissue inflammation and insulin resistance in mice.” PLoS One 4:e7250 (2009)
  6. Chakrabarti SK, Cole BK, Wen Y, Keller SR, and Nadler JL. “12/15-lipoxygenase products induce inflammation and impair insulin signaling in 3T3-L1 adipocytes.” Obesity 17:1657-1663 (2009)
  7. Min JK, Kim YM, Kim SW, Kwon MC, Kong YY, Hwang IK, Won MH, Rho J, and Kwon YG. “TNF-related activation-induced cytokine enhances leukocyte adhesiveness: induction of ICAM-1 and VCAM-1 via TNF receptor-associated factor and protein kinase C-dependent NF-kappaB activation in endothelial cells.” J Immunol 175: 531-540 (2005)
  8. Kim JJ and Sears DD. “TLR4 and Insulin Resistance.” Gastroenterol Res Pract doi:10./2010/212563 (2010)
  9. Bubici C, Papa S, Dean K, and Franzoso G. “Mutual cross-talk between reactive oxygen species and nuclear factor-kappa B: molecular basis and biological significance.” Oncogene 25: 6731-6748 (2006)
  10. Li H, Ruan XZ, Powis SH, Fernando R, Mon WY, Wheeler DC, Moorhead JF, and Varghese Z. “EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: Evidence for a PPAR-gamma-dependent mechanism.” Kidney Int 67: 867-874 (2005)
  11. Kawashima A, Harada T, Imada K, Yano T, and Mizuguchi K. “Eicosapentaenoic acid inhibits interleukin-6 production in interleukin-1beta-stimulated C6 glioma cells through peroxisome proliferator-activated receptor-gamma.” Prostaglandins LeukotEssent Fatty Acids 79: 59-65 (2008)
  12. Chambrier C, Bastard JP, Rieusset J, Chevillotte E, Bonnefont-Rousselot D, Therond P, Hainque B, Riou JP, Laville M, and Vidal H. “Eicosapentaenoic acid induces mRNA expression of peroxisome proliferator-activated receptor gamma.” Obes Res 10: 518-525 (2002)
  13. Mas E, Woodman RJ, Burke V, Puddey IB, Beilin LJ, Durand T, and Mori TA. “The omega-3 fatty acids EPA and DHA decrease plasma F(2)-isoprostanes.” Free Radic Res 44: 983-990 (2010)
  14. Lee JY, Plakidas A, Lee WH, Heikkinen A, Chanmugam P, Bray G, and Hwang DH. “Differential modulation of Toll-like receptors by fatty acids: preferential inhibition by n-3 polyunsaturated fatty acids.” J Lipid Res 44: 479-486 (2003)
  15. Crispo JA, Ansell DR, Piche M, Eibl JK, Khaper N, Ross GM, and Tai TC. “Protective effects of polyphenolic compounds on oxidative stress-induced cytotoxicity in PC12 cells.” Can J Physiol Pharmacol 88: 429-438 (2010)
  16. Romier B, Van De Walle J, During A, Larondelle Y, and Schneider YJ. “Modulation of signaling nuclear factor-kappaB activation pathway by polyphenols in human intestinal Caco-2 cells.” Br J Nutr 100: 542-551 (2008)
  17. Yee LD, Lester JL, Cole RM, Richardson JR, Hsu JC, Li Y, Lehman A, Belury MA, and Clinton SK. “Omega-3 fatty acid supplements in women at high risk of breast cancer have dose-dependent effects on breast adipose tissue fatty acid composition.” Am J Clin Nutr 91: 1185-1194 (2010)

Hard times are ahead

Last month was a red-letter month for the future of mankind as the world population passed 7 billion. Unfortunately, this fact dovetails with recent research that indicates it is likely that one-half of all Americans will be diabetic by 2050 (1).

The combination of these two trends does not bode well for the future. To begin with, how are we going to feed all these people? Most of the arable land on the planet is already under cultivation. Furthermore, urbanization is destroying prime cropland at a rapid pace.

Added to these facts is that the diversity of most of the world’s calories is rapidly decreasing. Currently the five top sources of calories in the world are corn, soybeans, wheat, rice and potatoes (as well as its kissin’ cousin cassava, which is incredibly poor in protein and nutrients). The first two crops (corn and soy) are rich sources of omega-6 fatty acids. In addition, corn, wheat, and rice provide extremely high-glycemic carbohydrates that can be easily refined to last forever and make thus a wide variety of processed foods. (Potatoes and cassava tend to decompose rapidly and can’t be easily refined, except perhaps as potato chips). As a consequence, omega-6 fatty acids and refined carbohydrates are now the cheapest form of calories in the world. In fact, it is estimated that they are 400 times less expensive per calorie than fresh fruits and vegetables.

So how can you feed this growing population of more than 7 billion people? The answer is easy—produce even more refined carbohydrates and omega-6 fatty acids.

Unfortunately, feeding the growing population of the world with cheap omega-6 fatty acids and refined carbohydrates is exactly the best way to increase cellular inflammation and drive the development of diabetes (2). It is estimated that by 2050 diabetes will be the primary non-infectious disease on the planet. This is equally bad news as it is also the most expensive chronic disease to treat on a long-term basis.

Today, more than 26 percent of all Americans older than 65 has diabetes. If the estimates of increased diabetes are correct (1), then it is likely that the number of Americans older than 65 in 2050 with diabetes may be greater than 50 percent. The current level of diabetes is the primary reason why our health-care expenses are spiraling out of control. If you double number of older Americans with diabetes by 2050, there is no way the current health-care system, as we know it can possibly survive. Add to the fact that once you have diabetes, you are 2-4 times more likely to develop heart disease and Alzheimer’s. It is not a very pleasant picture of the future of health care in America.

What can you do about it? On a global basis, not much unless you would like to see an apocalyptic event that reduces the population from 7 billion to a more manageable 1-2 billion individuals. Of course, this is highly unlikely. However, on the individual basis there is a lot you can do to protect yourself in the future. Simply take control of your future by focusing on managing cellular inflammation for a lifetime by following an anti-inflammatory diet. This may be your only real health security in times of increasing demands on the planet’s resources to produce food. There is no question that we have other troubles brewing like climate change, decreasing water supplies, and decreasing cheap energy, all of which will also impact the cost of food, driving more individuals toward inexpensive sources of calories no matter what the health consequences. But the rise of diabetes will occur first.

Old folks like myself will probably be OK, but the future generations will take the brunt of trouble brewing ahead.

References

  1. Boyle JP , Thompson TJ, Gregg EW, Barker LE, and Williamson DF. “Projection of the year 2050 burden of diabetes in the US adult population: dynamic modeling of incidence, mortality, and prediabetes prevalence.” Population Health Metrics 8:29 (2010)
  2. Sears B. “Toxic Fat.” Thomas Nelson. Nashville, TN (2008)

Pass the salt please?

One of the great “truths” in cardiovascular medicine is that to prevent stroke and cardiovascular death you reduce your salt intake. But is it true? A new analysis of the existing literature from the Cochrane Library indicates this may not be the case (1). Analyzing a great number of published studies, researchers came to the conclusion that there is no strong evidence to support the idea that salt restriction reduces cardiovascular disease or all-cause mortality in people with either normal or increased blood pressure. Furthermore, they found that while reducing salt intake did decrease blood pressure, it also increased the risk of all-cause death in people with existing congestive heart failure.

If that wasn’t enough, an article in the May 4 issue of the Journal of the American Heart Association found that low salt increased the risk of death from heart attacks and stokes, while not reducing blood pressure (2). This study was done with middle-aged Europeans and followed them for nearly eight years. During this time, the less salt they consumed, the greater the number who died of heart disease.

Needless to say, the American Heart Association (the same people who recommend eating lots of omega-6 fats) was enraged, similar to the Wizard of Oz telling Dorothy to ignore the man behind the curtain.

So why might restriction of salt consumption cause increased heart attacks? The reason may be due to increased insulin resistance induced by salt restriction (3). Insulin resistance increases insulin levels, and if that is combined with increased consumption of omega-6 fatty acids (remember the American Heart Association), you now have a sure-fire prescription to produce more arachidonic acid. It’s the inflammatory eicosanoids derived from arachidionic acid that would cause inflammation in the arterial wall leading to a heart attack.

This is not to say that some people are not salt-sensitive (African-Americans are particularly so), but I believe the problem is more a matter of balance. You need some sodium, but you also need potassium to balance it. This is confirmed by a recent study from Harvard Medical School that demonstrates that the higher the sodium-to-potassium ratio in the blood, the greater the likelihood of cardiovascular mortality (4). The relationship for increased death was significantly greater for a high sodium-to-potassium level than simply the sodium level itself.

Getting sodium in your diet is easy (sprinkle salt on your food), but getting adequate levels of potassium means eating a lot of fruits and vegetables. So rather than restricting salt intake or taking drugs (i.e. diuretics) to reduce the levels of sodium in the body, think about eating more fruits and vegetables if your goal is to reduce the likelihood of a heart attack. Oh, yes, also ignore the advice of American Heart Association and take more omega-3 and less omega-6 fatty acids.

References

  1. Taylor, RS, Ashton KE, Moxham T, Hooper L and Ebrahim S. “Reduced dietary salt for the prevention of cardiovascular disease.” Cochrane Database of Systematic Reviews DOI: 10.1002/14651858.CD009217 (2011)
  2. Stolarz-Skrzypek K, Kuznetsova T, Thijs L, Tikhonoff V, Seidlerova J, Richart T, Jin Y, Olszanecka A, Malyutina S, Casiglia E, Filipovsky J, Kawecka-Jaszcz K, Nikitin Y, and Staessen JA. “Fatal and nonfatal outcomes, incidence of hypertension, and blood pressure changes in relation to urinary sodium excretion.” JAMA 305: 1777-1785 (2011)
  3. Alderman MH. “Evidence relating dietary sodium to cardiovascular disease.” J Am Coll Nutr 25: 256S-261S (2006)
  4. Yang Q, Liu T, Kuklina EV, Flanders WD, Hong Y, Gillespie C, Chang M-H, Gwinn M, Dowling N, Khoury MJ, and Hu FB. “Sodium and potassium intake and morality among US adults.” Arch Intern Med 171: 1183-1191 (2011)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

The key to a healthy gut

Most people think all you need for a healthy gut is to consume bacterial-fortified yogurt products. In reality, the balance of bacteria in your gut may hold a key toward managing systemic inflammation in our bodies.

First of all, there are a lot of bacteria in our guts. The human body contains about 100 trillion cells, but the number of bacteria in the gut is 10 times greater in number. Furthermore, these bacteria are not just taking up space; they are actually providing numerous useful functions that make them a symbiotic “organ” to our own body. In particular, they can ferment carbohydrates to provide additional energy, make various vitamins, break down toxins we might ingest, and help prevent the growth of pathogenic bacteria.

Although there are literally millions of different bacteria in the world, only about 500 species actually reside in our guts. We also know that these gut bacteria can be further divided into three distinct bacterial ecosystems (1). Just like there are four unique blood groups that can classify every human, we also have three distinct bacterial systems. Once one of these systems becomes established in the gut, it begins to alter the gut environment that only certain species of other bacteria can follow and safely begin their symbiotic relationship with us.

So how does each ecosystem of bacteria keep out the bad apples (like Salmonella)? First of all, the bacteria in each distinct ecosystem have to alert our own immune cells in the intestine that they are friends, not foes. Apparently they have learned how to suppress the immune system in our own cells so they can co-exist in our gut (2). However, I believe even though these ecosystems of bacteria can be recognized as friends and not foes, they still need unique nutrients to help them act as the first line of defense against millions of other harmful bacteria.

Those nutrients are polyphenols. In the plant world, these polyphenols act as antibiotics against microbial attack. There is evidence that the “good” bacteria in our gut can use them as a means to help ward off invading bacteria that threaten our own unique bacterial fingerprint. Of course, the only way we can continue to help our unique bacterial partners in our gut is to continue to eat lots of fruits and vegetables that are rich in polyphenols. That’s why your grandmother told you to eat an apple a day to keep the doctor away.

References

  1. Arumugam M, Raes J, Pelletier E, et al. “Enterotypes of the human gut microbiome.” Nature DOI: 10.1038/nature09944 (2011)
  2. Round JL, Lee SM, Li Jennifer, Tran G, Bana J, Chatila TA and Mazmanian SK. “The toll-like receptor 2 pathway establishes colonization by a commensal of the human microbiota.” Science DOI:10.1126/scienc.1206095 (2011)
  3. Moreno S, Scheyer T, Romano CS, and Vojnov AA. “Antioxidant and antimicrobial activities of rosemary extracts linked to their polyphenol composition.” Free Radic Res 40: 223-231 (2006)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

Zone diet validation studies

Weight Loss

Any diet that restricts calories will result in equivalent weight loss. However, the same doesn’t hold true as to what the source of that weight loss is. Weight loss from either dehydration (such as ketogenic diets) or cannibalization of muscle and organ mass (such as low-protein diets) has no health benefits. Only when the weight loss source is from stored fat do you gain any health benefits. Here the Zone diet has been shown to be superior to all other diets in burning fat faster (1-4). It has been demonstrated that if a person has a high initial insulin response to a glucose challenge, then the Zone diet is also superior in weight loss (5,6). A recent study from the New England Journal of Medicine indicates that a diet composition similar to the Zone diet is superior to other compositions in preventing the regain of lost weight (7). This is probably caused by the increased satiety induced by the Zone diet compared to other diets (1,8,9).

Reduction of cellular inflammation

There is total agreement in the research literature that the Zone diet is superior in reducing cellular inflammation (10-12). Since cellular inflammation is the driving force for chronic disease, then this should be the ultimate goal of any diet. Call me crazy for thinking otherwise.

Heart disease

It is ironic that the Ornish diet is still considered one of the best diets for heart disease, since the published data indicates that twice as many people had fatal heart attacks on the Ornish diet compared to a control diet (13). This is definitely the case of don’t confuse me with the facts. On the other hand, diets with the same balance of protein, carbohydrate and fat as the Zone diet has have been shown to be superior in reducing cardiovascular risk factors, such as cholesterol and fasting insulin (14,15).

Diabetes

The first publication validating the benefits of the Zone diet in treating diabetes appeared in 1998 (16). Since that time there have been several other studies indicating the superiority of the Zone diet composition for reducing blood glucose levels (17-20). In 2005, the Joslin Diabetes Research Center at Harvard Medical School announced its new dietary guidelines for treating obesity and diabetes. These dietary guidelines were essentially identical to the Zone diet. Studies done at the Joslin Diabetes Research Center following those dietary guidelines confirm the efficacy of the Zone diet to reduce diabetic risk factors (21). If the Zone diet isn’t recommended for individuals with diabetes, then someone should tell Harvard.

Ease of use

The Zone diet simply requires balancing one-third of your plate with low-fat protein with the other two-thirds coming from fruits and vegetables (i.e. colorful carbohydrates). Then you add a dash (that’s a small amount) of heart-healthy monounsaturated fats. The Zone diet is based on a bell-shaped curve balancing low-fat protein and low-glycemic-index carbohydrates, not a particular magic number. If you balance the plate as described above using your hand and your eye, it will approximate 40 percent of the calories as carbohydrates, 30 percent of calories as protein, and 30 percent of the calories as fat. Furthermore, it was found in a recent Stanford University study that the Zone diet provided greater amounts of micronutrients on a calorie-restricted program than any other diet (22).

Eventually all dietary theories have to be analyzed in the crucible of experimentation to determine their validity. So far in the past 13 years since I wrote my first book, my concepts of anti-inflammatory nutrition still seem to be at the cutting edge.

References

  1. Skov AR, Toubro S, Ronn B, Holm L, and Astrup A. “Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity.” Int J Obes Relat Metab Disord 23: 528-536 (1999)
  2. Layman DK, Boileau RA, Erickson DJ, Painter JE, Shiue H, Sather C, and Christou DD. “A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women.” J Nutr 133: 411-417 (2003)
  3. Fontani G, Corradeschi F, Felici A, Alfatti F, Bugarini R, Fiaschi AI, Cerretani D, Montorfano G, Rizzo AM, and Berra B. “Blood profiles, body fat and mood state in healthy subjects on different diets supplemented with omega-3 polyunsaturated fatty acids.” Eur J Clin Invest 35: 499-507 (2005)
  4. Layman DK, Evans EM, Erickson D, Seyler J, Weber J, Bagshaw D, Griel A, Psota T, and Kris-Etherton P. “A moderate-protein diet produces sustained weight loss and long-term changes in body composition and blood lipids in obese adults.” J Nutr 139: 514-521 (2009)
  5. Ebbeling CB, Leidig MM, Feldman HA, Lovesky MM, and Ludwig DS. “Effects of a low-glycemic-load vs low-fat diet in obese young adults: a randomized trial.” JAMA 297: 2092-2102 (2007)
  6. Pittas AG, Das SK, Hajduk CL, Golden J, Saltzman E, Stark PC, Greenberg AS, and Roberts SB. “A low-glycemic-load diet facilitates greater weight loss in overweight adults with high insulin secretion but not in overweight adults with low insulin secretion in the CALERIE Trial.” Diabetes Care 28: 2939-2941 (2005)
  7. Larsen TM, Dalskov SM, van Baak M, Jebb SA, Papadaki A, Pfeiffer AF, Martinez JA, Handjieva-Darlenska T, Kunesova M, Pihlsgard M, Stender S, Holst C, Saris WH, and Astrup A. “Diets with high or low protein content and glycemic index for weight-loss maintenance.” N Engl J Med 363: 2102-2113 (2010)
  8. Ludwig DS, Majzoub JA, Al-Zahrani A, Dallal GE, Blanco I, Roberts SB, Agus MS, Swain JF, Larson CL, and Eckert EA. “Dietary high-glycemic-index foods, overeating, and obesity.” Pediatrics 103: E26 (1999)
  9. Agus MS, Swain JF, Larson CL, Eckert EA, and Ludwig DS. “Dietary composition and physiologic adaptations to energy restriction.” Am J Clin Nutr 71: 901-907 (2000)
  10. Pereira MA, Swain J, Goldfine AB, Rifai N, and Ludwig DS. “Effects of a low-glycemic-load diet on resting energy expenditure and heart disease risk factors during weight loss.” JAMA 292: 2482-2490 (2004)
  11. Pittas AG, Roberts SB, Das SK, Gilhooly CH, Saltzman E, Golden J, Stark PC, and Greenberg AS. “The effects of the dietary glycemic load on type 2 diabetes risk factors during weight loss.” Obesity 14: 2200-2209 (2006)
  12. Johnston CS, Tjonn SL, Swan PD, White A, Hutchins H, and Sears B. “Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets.” Am J Clin Nutr 83: 1055-1061 (2006)
  13. Ornish D, Scherwitz LW, Billings JH, Brown SE, Gould KL, Merritt TA, Sparler S, Armstrong WT, Ports TA, Kirkeeide RL, Hogeboom C, and Brand RJ, “Intensive lifestyle changes for reversal of coronary heart disease.” JAMA 280: 2001-2007 (1998)
  14. Wolfe BM and Piche LA. “Replacement of carbohydrate by protein in a conventional-fat diet reduces cholesterol and triglyceride concentrations in healthy normolipidemic subjects.” Clin Invest Med 22: 140-1488 (1999)
  15. Dumesnil JG, Turgeon J, Tremblay A, Poirier P, Gilbert M, Gagnon L, St-Pierre S, Garneau C, Lemieux I, Pascot A, Bergeron J, and Despres JP. “Effect of a low-glycaemic index, low-fat, high-protein diet on the atherogenic metabolic risk profile of abdominally obese men.” Br J Nutr 86:557-568 (2001)
  16. Markovic TP, Campbell LV, Balasubramanian S, Jenkins AB, Fleury AC, Simons LA, and Chisholm DJ. “Beneficial effect on average lipid levels from energy restriction and fat loss in obese individuals with or without type 2 diabetes.” Diabetes Care 21: 695-700 (1998)
  17. Layman DK, Shiue H, Sather C, Erickson DJ, and Baum J. “Increased dietary protein modifies glucose and insulin homeostasis in adult women during weight loss.” J Nutr 133: 405-410 (2003)
  18. Gannon MC, Nuttall FQ, Saeed A, Jordan K, and Hoover H. “An increase in dietary protein improves the blood glucose response in persons with type 2 diabetes.” Am J Clin Nutr 78: 734-741 (2003)
  19. Nuttall FQ, Gannon MC, Saeed A, Jordan K, and Hoover H. “The metabolic response of subjects with type 2 diabetes to a high-protein, weight-maintenance diet.” J Clin Endocrinol Metab 2003 88: 3577-3583 (2003)
  20. Gannon MC and Nuttall FQ. “Control of blood glucose in type 2 diabetes without weight loss by modification of diet composition.” Nutr Metab (Lond) 3: 16 (2006)
  21. Hamdy O and Carver C. “The Why WAIT program: improving clinical outcomes through weight management in type 2 diabetes.” Curr Diab Rep 8: 413-420 (2008)
  22. Gardner CD, Kim S, Bersamin A, Dopler-Nelson M, Otten J, Oelrich B, and Cherin R. “Micronutrient quality of weight-loss diets that focus on macronutrients: results from the A TO Z study.” Am J Clin Nutr 92: 304-312 (2010)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

The demise of the Mediterranean diet?

This week is Mediterranean diet week. Unfortunately after 2,000 years, no one really knows what the Mediterranean diet actually consists of. Is it the Italian, Spanish, Moroccan, Egyptian, Greek or Lebanese Mediterranean diet? Each diet is very different from each other. What is clear is that people in the Mediterranean region are becoming fatter and less healthy (1).

Part of the reason for the demise of the benefits of a “Mediterranean diet” is the time it takes to prepare a quality meal. It takes time to purchase fresh vegetables. It takes even more time to prepare them. In a world without globalization, you have a lot more time. Now you are competing with every human on the face of the globe for a job, and the result is time-compression. The first casualty of this time-compression effect of globalization is the inability to cook and consume good food containing high-quality food ingredients. Another sinister aspect of globalization is the reduction in the number of food ingredients being used by the general population. In particular, those food ingredients are the least expensive, have an extended shelf life and can be made into very inexpensive, convenient, and portable (not requiring a knife or fork to eat) processed foods. The only food ingredients that meet those requirements are cheap refined grains and cheap refined vegetable oils. And the low-cost producer of these food ingredients is not China, but the United States.

Fruits and vegetables are really expensive unless you grow them yourself. With urbanization of the Mediterranean region, most people now rely on processed foods and restaurants for their meals. Not surprisingly, is the consumption of cheap, refined grains and vegetable oils, which in the past were alien components to the Mediterranean diet (regardless of the location). Now they have replaced vegetables, fruits and olive oil (the primary food ingredients of a Mediterranean diet) because they are cheaper. For example, vegetables and fruits are now 400 times more expensive for the same number of calories as cheap, refined grains imported from America. Corn oil from America is now five times cheaper than olive oil produced in the Mediterranean region.

The people in the Mediterranean regions are eating the same foods that have produced the Perfect Nutritional Storm in America. This explains why 75 percent of Greeks are now overweight or obese and more than half the populations of Italy, Spain and Portugal are now overweight or obese. They are making the right economic choices (cheap food), but the wrong health choices (an increasingly inflammatory diet).

Even if you were to go back to the original Mediterranean diet (circa Roman times), it is apparently still not the best diet for health. This was demonstrated in a recent publication that compared the Mediterranean diet (50 percent calories as carbohydrates, 20 percent calories as protein, and 30 percent of calories as fat) to a diet that contained 40 percent carbohydrates, 30 percent protein, and 30 percent fat in a cross-over study. The higher protein, lower carbohydrate diet was more satiating and had better clinical results, especially in hormonal responses, than a real Mediterranean diet (2). Besides having a different macronutrient ratio, the other diet was extremely limited in grains and dairy products compared to the Mediterranean diet.

So if you want to follow a diet that is the evolution of the Mediterranean diet, then make it a diet that is higher in low-fat protein, lower in carbohydrates (but rich in vegetables and fruits) and low in omega-6 fats. Sure sounds like the Zone diet, but call me crazy (3).

References

  1. Ciezaldlo A. “Does the Mediterranean diet even exist?” New York Times April 1, 2011
  2. Jonsson T, Granfeldt Y, Erlanson-Albertsson C, Ahren B, and Lindeberg S. “A paleolithic diet is more satiating per calorie than a Mediterranean-like diet in individuals with ischemic heart disease.” Nutr Metab 7:85 (2010)
  3. Sears B. “The Zone.” Regan Books. New York, NY (1995)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

Fish oil and fat loss

I have often said, “It takes fat to burn fat”. As I describe in my book “Toxic Fat,” increased cellular inflammation in the fat cells turns them into “fat traps” (1). This means that fat cells become increasingly compromised in their ability to release stored fat for conversion into chemical energy needed to allow you to move around and survive. As a result, you get fatter, and you are constantly tired and hungry.

One of the best ways to reduce cellular inflammation in the fat cells is by increasing your intake of omega-3 fatty acids. This was demonstrated in a recent article that indicated supplementing a calorie-restricted diet with 1.5 grams of EPA and DHA per day resulted in more than two pounds of additional weight loss compared to the control group in a eight-week period (2).

How omega-3 fatty acids help to ”burn fat faster” is most likely related to their ability to reduce cellular inflammation in the fat cells (3,4) and to increase the levels of adiponectin (5). Both mechanisms will help relax a “fat trap” that has been activated by cellular inflammation.

However, there is a cautionary note. This is because omega-3 fatty acids are very prone to oxidation once they enter the body. This is especially true relative to the enhanced oxidation of the LDL particles (6-9).

This means that to get the full benefits any fish oil supplementation, you have to increase your intake of polyphenols to protect the omega-3 fatty acids from oxidation. How much? I recommend at least 8,000 additional ORAC units for every 2.5 grams of EPA and DHA that you add to your diet. That's about 10 servings per day of fruits and vegetables, which should be no problem if you are following the Zone diet. If not, then consider taking a good polyphenol supplement.

Once you add both extra fish oil and polyphenols to a calorie-restricted diet, you will burn fat faster without any concern about increased oxidation in the body that can lead to accelerated aging.

References

  1. Sears B. “Toxic Fat.” Thomas Nelson. Nashville, TN (2008)
  2. Thorsdottir I, Tomasson H, Gunnarsdottir I, Gisladottir E, Kiely M, Parra MD, Bandarra NM, Schaafsma G, and Martinez JA. “Randomized trial of weight-loss diets for young adults varying in fish and fish oil content.” Int J Obes 31: 1560-1566 (2007)
  3. Huber J, Loffler M, Bilban M, Reimers M, Kadl A, Todoric J, Zeyda M, Geyeregger R, Schreiner M, Weichhart T, Leitinger N, Waldhausl W, and Stulnig TM. “Prevention of high-fat diet-induced adipose tissue remodeling in obese diabetic mice by n-3 polyunsaturated fatty acids.” Int J Obes 31: 1004-1013 (2007)
  4. Todoric J, Loffler M, Huber J, Bilban M, Reimers M, Kadl A, Zeyda M, Waldhausl W, and Stulnig TM. “Adipose tissue inflammation induced by high-fat diet in obese diabetic mice is prevented by n-3 polyunsaturated fatty acids.” Diabetologia 49: 2109-2119 (2006)
  5. Krebs JD, Browning LM, McLean NK, Rothwell JL, Mishra GD, Moore CS, and Jebb SA. “Additive benefits of long-chain n-3 polyunsaturated fatty acids and weight-loss in the management of cardiovascular disease risk in overweight hyperinsulinaemic women.” Int J Obes 30: 1535-1544 (2006)
  6. Pedersen H, Petersen M, Major-Pedersen A, Jensen T, Nielsen NS, Lauridsen ST, and Marckmann P. “Influence of fish oil supplementation on in vivo and in vitro oxidation resistance of low-density lipoprotein in type 2 diabetes.” Eur J Clin Nutr 57: 713-720 (2003)
  7. Turini ME, Crozier GL, Donnet-Hughes A, and Richelle MA. “Short-term fish oil supplementation improved innate immunity, but increased ex vivo oxidation of LDL in man–a pilot study.” Eur J Nutr 40: 56-65 (2001)
  8. Stalenhoef AF, de Graaf J, Wittekoek ME, Bredie SJ, Demacker PN, and Kastelein JJ. “The effect of concentrated n-3 fatty acids versus gemfibrozil on plasma lipoproteins, low-density lipoprotein heterogeneity and oxidizability in patients with hypertriglyceridemia.” Atherosclerosis 153: 129-138 (2000)
  9. Finnegan YE. Minihane AM, Leigh-Firbank EC, Kew S, Meijer GW, Muggli R, Calder PC, and Williams CM. “Plant- and marine-derived n-3 polyunsaturated fatty acids have differential effects on fasting and postprandial blood lipid concentrations and on the susceptibility of LDL to oxidative modification in moderately hyperlipidemic subjects.” Am J Clin Nutr 77: 783-795 (2003)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

Omega-3 fatty acids and blood pressure

Blood Pressure CuffIt was recognized many years ago that fish oil has a dose-dependent effect on lowering blood pressure (1). So how does it do it? There are a lot of different ways.

The first is the ability of the omega-3 fatty acids in fish oil to alter the levels of a group of hormones known as eicosanoids (2,3). These are the hormones that cause blood vessels to contract, thereby increasing the pressure needed to pump blood through the arteries. The omega-3 fatty acids, especially eicosapentaenoic acid (EPA), inhibit both the synthesis and release of the omega-6 fatty acid arachidonic acid (AA) that is the molecular building block necessary to produce those eicosanoids that cause constriction of blood vessels.

The second way that fish oil helps reduce blood pressure is to accelerate weight loss. When you lose excess weight, blood pressure invariably decreases. A recent trial has indicated that when you add fish oil to a calorie-restricted diet, there is greater weight loss (4). This study was followed by an additional trial that indicated when adding fish oil to a weight-reduction diet, there was a further effect on lowering blood pressure (5). So how does fish oil help you lose excess weight? The answer lies in the ability of the omega-3 fatty acids in fish oil to reduce cellular inflammation in the fat cells (6). It's that cellular inflammation that makes you fat and keeps you fat. Reducing that cellular inflammation in the fat cells is the key to weight loss.

Finally another cause of increased blood pressure is increased stress. It was shown in 2003 that high levels of fish oil reduce the rise of blood pressure induced by mental stress (7).

Of course, the best way to reduce blood pressure is to follow an anti-inflammatory diet rich in omega-3 fatty acids. That means a diet rich in fruits and vegetables with adequate levels of low-fat protein and low levels of omega-6 and saturated fats. It's also commonly known as the Zone diet.

References:

  1. Morris MC, Sacks F, and Rosner B. “Does fish oil lower blood pressure? A meta-analysis of controlled trials.” Circulation 88: 523-533 (1993)
  2. Sears B. “The Zone.” Regan Books. New York, NY (1995)
  3. Sears B. “The OmegaRx Zone.” Regan Books. New York, NY (2002)
  4. Thorsdottir I, Tomasson H, Gunnarsdottir I, Gisladottir E, Kiely M, Parra MD, Bandarra NM, Schaafsma G, and Martinez JA. “Randomized trial of weight-loss diets for young adults varying in fish and fish oil content.” Int J Obes 31: 1560-1566 (2007)
  5. Ramel A, Martinez JA, Kiely M, Bandarra NM, and Thorsdottir I. “Moderate consumption of fatty fish reduces diastolic blood pressure in overweight and obese European young adults during energy restriction.” Nutrition 26: 168-174 (2010)
  6. Sears B. “Toxic Fat.” Thomas Nelson. Nashville, TN (2008)
  7. Delarue J, Matzinger O, Binnert C, Schneiter P, Chiolero R, and Tappy L. “Fish oil prevents the adrenal activation elicited by mental stress in healthy men.” Diabetes Metab 29: 289-295 (2003)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.

What is the Mediterranean diet?

The mediterranean dietToday we continually hear about the health benefits of following a Mediterranean diet. For example, a recent analysis of more than 50 published studies indicated that a Mediterranean diet would lead to a 30-percent reduction in metabolic syndrome (1). Since metabolic syndrome can be considered pre-diabetes, the public health implications are enormous. However, are we talking about the Spanish Mediterranean diet or the Italian, or the Moroccan, the Egyptian or the Lebanese versions? Here is the basic problem with all diets: Trying to define them correctly.

In order to compare one diet to another, each diet must ultimately be defined by its balance of the macronutrients (protein, carbohydrate and fat). This is because the macronutrient balance determines hormonal responses generated by that diet (2).

A Mediterranean diet can be considered to contain approximately 50 percent of the calories as carbohydrates, 20 percent of the calories as protein and 30 percent of the calories as fat. This is a higher protein-to-carbohydrate balance than is found in the usually recommended “healthy” diets for weight loss and cardiovascular health. As a result, this difference in the balance of the protein-to-carbohydrate ratio will generate different hormonal responses between the two types of diets, especially in terms of reducing insulin responses and controlling cellular inflammation.

This is important since it is excess insulin that makes you fat and keeps you fat, and it's cellular inflammation that makes you sick. Since insulin levels are determined by the protein-to-carbohydrate ratio, would more protein and less carbohydrate generate an even better response? Of course it would. That is why the Zone diet contains 40 percent of the calories as carbohydrates, 30 percent of the calories as protein, and 30 percent of the calories as fat. This improved protein-to-carbohydrate balance means lower insulin levels and less cellular inflammation.

Why stop there? Let's just continue reducing the carbohydrates. Now you get low-carbohydrate diets, like the Atkins diet. Unlike the Zone diet, carbohydrates are no longer the primary macronutrient in a true low-carbohydrate diet. Now the primary macronutrient is fat. Using these low-carbohydrate diets creates some real problems by generating an abnormal metabolic state known as ketosis. This occurs when you don't have enough carbohydrates (fewer than 20 percent of total calories) in the diet to metabolize fat completely to carbon dioxide and water. When that happens, your blood vessels lose their elastic nature, (3) increasing the risk of a heart attack (4). This is probably a consequence of lowering insulin too much as well as increasing inflammatory mediators (3). If you are trying to lose weight, increasing the likelihood of a heart attack is not a good idea. So it seems you need some carbohydrates, but not too few if your goal is to lose weight safely.

That's why people (as well as physicians and diet editors) get confused when they read articles in the New England Journal of Medicine talking about low-carbohydrate diets for weight loss when such diets actually contain 40 percent carbohydrates (5). To be correct, they should use the term “the Zone diet” instead of a “low-carbohydrate diet” to be correct. Despite the poor dietary description used in this article, the “low-carbohydrate” (aka the Zone) diet generated greater weight loss after two years, a greater reduction in the total cholesterol-to-HDL cholesterol (a marker of future cardiovascular risk), a greater decrease in triglycerides and a greater decrease in inflammatory markers when compared to a Mediterranean diet or the always-recommended low-fat diet (5). That's why you do controlled clinical trials instead of guessing what the best might be.

So if you want to lose weight and reduce your future heart disease risk, it seems prudent to follow the Zone diet and make most of your carbohydrates colorful ones (i.e., fruits and vegetables) and add olive oil and nuts for fat instead of using vegetable oils and saturated fats just as I recommended more than 15 years ago (2). Just call it the Mediterranean Zone diet. Now everyone is not only happy, but also they are finally using the proper diet terminology.

References

  1. Kastorini C-M, Milionis HJ, Esposito K, Giuglian D, Goudevnos JA, and Panagiotakos DB. “The effect of Mediterranean diet on metabolic syndrome and its components.” J Am Coll Cardiol 57: 1299-1313 (2011)
  2. Sears B. “The Zone.” Regan Books. New York, NY (1995)
  3. Buscemi S, Verga S, Tranchina MR, Cottone S, and Cerasola G. “Effects of hypocaloric very-low-carbohydrate diet vs. Mediterranean diet on endothelial function in obese women.” Eur J Clin Invest 39: 339-347 (2009)
  4. Yeboah J, Crouse JR, Hsu FC, Burke GL, and Herrington DM. “Brachial flow-mediated dilation predicts incident cardiovascular events in older adults.” J Am Coll Cardio 51: 997-1002 (2008)
  5. Shai I, Schwarzfuchs D, Henkin Y, Shahaar DR, Witkow S, Greenberg I, Golan R, Fraser D, boltin A, Vardi H, Tangi-Roxental O, Zuk-Ramot R, Sarusi B, Fricner D, Schwartz Z, Sheiner E, Marko R, Katorza E, Thiery J, Fielder GM, Bluher M, Stumvoll M and Stamper MJ. “Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet.” N Engl J Med 359: 229-241 (2008)

Nothing contained in this blog is intended to be instructional for medial diagnosis or treatment. If you have a medical concern or issue, please consult your personal physician immediately.