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011223--Meditteranean-vs.-Zone-Diet

The Zone Diet versus the Mediterranean Diet

For the past six years, the Mediterranean diet has been voted the Best Diet in America as well as the best diet to manage diabetes. It’s remarkable since no one can define the Mediterranean diet. No one knows how many calories you should consume each day or how many grams of protein or fat should be consumed daily on the Mediterranean diet. There is also no distinction between low-glycemic or high-glycemic carbohydrates, protein-to-carbohydrate balance, etc. It certainly doesn’t give a strong feeling of robust science for the best diet in America as I pointed out in my book, The Mediterranean Zone (1).

            Furthermore, the initial results indicating the breakthrough of the Mediterranean diet published in 2013 had to be retracted and republished because of severe methodological problems in the study (2). Nonetheless, the lack of good science doesn’t prevent the Mediterranean diet from being consistently voted the top diet for general health and diabetes management for the past six years.

            A new study presents much more controlled research that can be used to compare the benefits of the Mediterranean diet to the Zone diet (3). The study was a direct head-on comparison to the Zone diet, so it was a “winner take all.” The study was conducted in a metabolic ward in an Italian hospital where all the food was provided to the subjects. The subjects also had significant insulin resistance (HOMA-IR > 4). Since the subjects were confined to the hospital, their dietary intake was tightly monitored. The control group received a calorie-restricted Mediterranean diet (500 calories less than needed to maintain their current weight) consisting of 55 percent carbohydrates, 20 percent protein, and 25 percent fat. The active group had the same level of calorie restriction but it was composed of 40 percent carbohydrates, 30 percent protein, and 30 percent fat. Although the authors cite this higher protein diet as a “high-protein Mediterranean diet,” it was identical to the Zone diet I described in 1995 (4). Furthermore, it was a crossover study since halfway through the study, the diets the subjects were consuming were switched after ten days to reduce any potential impact of individual metabolic characteristics of the subjects on the results.

The Results

The Zone diet demonstrated superior insulin resistance and hyperinsulinemia reductions compared to the Mediterranean diet.  But there is more. The Zone diet also reduced the variability of blood glucose levels, indicating better hormonal stability between meals than the Mediterranean diet. This result was hardly new since Harvard investigators reported similar results after a single Zone meal compared to an isocaloric meal containing a higher level of carbohydrates and a lower level of protein in 1998 (5). In addition, the Zone diet is the primary dietary program used by the Joslin Diabetes Research Center at Harvard Medical School for treating type 2 diabetes. The reason is that the Zone diet is defined and, more importantly it works (6-9).

            So why don’t you hear more about the Zone diet in the medical research literature? I think the primary reason appears to be that the researchers wish to believe they came up with the idea of the macronutrient balance of the Zone diet all on their own, even though the Zone Diet was granted a U.S. patent for the treatment of hyperinsulinemia and insulin resistance in 2000 (10). Furthermore, since more than six million books on the Zone diet have been sold in the United States since the publication of The Zone in 1995, it is not that no one has ever heard of the Zone diet.

            Another problem is understanding the underlying metabolic problem that causes what is loosely termed “insulin resistance. “ It’s insulin resistance that causes weight gain and diabetes. However, insulin resistance can be best understood as a general term to describe the disruption of your metabolism. Furthermore, insulin resistance is associated with many other chronic disease conditions other than obesity and type 2 diabetes. These other chronic diseases include heart disease and Alzheimer’s. However, the most likely molecular cause of insulin resistance is the inhibition of the master regulator of metabolism known as AMPK (11).

            To optimally activate AMPK, you need a dietary triad consisting of the calorie-restricted Zone diet coupled with adequate intakes of omega-3 fatty acids and polyphenols.  This is the Zone Nutritional System. Each of these nutritional interventions works synergistically with each other to increase AMPK activity.  Any single intervention is good but using all three simultaneously is powerful. The molecular mechanisms of their interactions are complicated, but nutrition is always more complex than simple pharmacology.

 

References

  1. Sears B. The Mediterranean Zone. Ballantine Books. New York, NY (2014)
  2. Estruch R et al. “Retraction and Republication: Primary Prevention of Cardiovascular Disease with a Mediterranean Diet. N Engl J Med 2013;368:1279-90 Retraction of Publication.” N Engl J Med. 378:2441-2442. doi: 10.1056/NEJMc1806491. (2018)
  3. Tettamanzi F et al. “A high-protein diet is more effective in improving insulin resistance and glycemic variability compared to a Mediterranean diet: A cross-over controlled inpatient dietary study. Nutrients 13:4380. doi: 10.3390/nu13124380. (2021)
  4. Sears B. The Zone. Regan Books. New York, NY (1995)
  5. Ludwig DS et al. “High glycemic index foods, overeating, and obesity.” Pediatrics 103:E26. doi: 10.1097/00008480-199908000-00005. (1999)
  6. Giusti J and Rizzott J. “Interpreting the Joslin Diabetes Center and Joslin Clinic clinical guideline for overweight and obese adults with type 2 diabetes.” Curr Diab Report 6:405-408. doi: 10.1007/s11892-006-0014-y. (2006)
  7. Hamdy O. “Diabetes weight management in clinical practice—the Why Wait model,” US Endocrinology 4:49–54. doi.org/10.17925/USE.2008.04.2.49. (2008)
  8. 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. doi: doi: 10.1007/s11892-008-0071-5. (2008)
  9. Hamdy O. et al. “Long-term effect of intensive lifestyle intervention on cardiovascular risk factors in patients with diabetes in real-world clinical practice: a 5-year longitudinal study.” BMJ Open Diabetes Res Care 5:e000259. doi: 10.1136/bmjdrc-2016-000259. (2017)
  10. Sears, B. “Method of and nutritional and pharmaceutical compositions for reduction of hyperinsulinemia.” U.S. Patent No. 6,140,304 (2000)
  11. Sears B and Saha A. “Dietary activation of AMP-activated protein kinase (AMPK) to treat insulin resistance.” Evolving Concepts in Insulin Resistance doi: http://dx.doi.org/10.5772/intechopen.103787. (2022)

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062524---Keto-Blog

Ketogenic Diets and Aging

Chances are, you or someone you know has tried the keto diet at some point in time. This high-fat, very low-carbohydrate eating plan appeals to many due to its promise of rapid weight loss. In this blog, Dr. Sears explores some of the latest scientific findings on ketogenic diets and provides caution before hopping on this trend. What is a Ketogenic Diet? The ketogenic diet is a high-fat, very low-carbohydrate eating plan. This significant reduction in carbohydrates to induce a metabolic state is called ketosis. This only occurs when there is not enough carbohydrates in your liver to completely convert fatty acids to carbon dioxide and water. The normal conversion generates the chemical energy (ATP) that keeps us alive. In the absence of ketosis, each fatty acid generates 108 molecules of ATP when oxidized in the mitochondria. Ketone bodies make less ATP when they are metabolized by mitochondria. How much less? About five times less. This is like switching the gasoline in your car from high-octane fuel to low octane fuel as ketone bodies increase in the blood. Furthermore, contrary to popular belief, ketones are not an ideal energy source for the brain, as glucose remains the preferred fuel for ATP production in brain cells. Lack of blood glucose is a highly stressful situation for the brain. This is why the body secretes the stress hormone cortisol from the adrenal glands during ketosis to breakdown protein and convert the amino acids into glucose for the brain. This explains why even under complete starvation for 38 days, the blood glucose levels never dropped below 68 mg/dL. This is still considered as a normal blood sugar level. Where did this blood glucose come from if there was none in the diet for 38 days? The answer is neo-glucogenesis primarily using lean body mass. Ketogenic Diets Pros and Cons Interest in ketogenic diets rises and falls about every 20 years. They’re very low-carbohydrate diets that claim that carbohydrates make you fat and keep you fat. This is simply not true. It is not carbohydrates per se but a disrupted metabolism that makes you fat. To be more specific, it is the inhibition of AMPK, the master regulator of your metabolism that makes you fat. Why? As AMPK activity increases, you burn stored fat faster. Frankly, I’ve always been amazed by the re-emergence of ketogenic diets. Eighteen years ago, I published the premier clinical study demonstrating that, under equal calorie intake in which all the food was provided to the subjects for six weeks, the Zone Diet was better than a ketogenic diet in reducing total weight, excess body fat, and inflammation. Now, a recent study revealed some more very concerning findings about the long-term effects of ketogenic diets. This new study indicated that following a keto diet causes a rise in senescent cells, popularly known as “zombie cells.” Zombie Cells are damaged cells that no longer divide but don't die. That’s bad enough, but zombie cells continue spreading inflammation throughout the body. As the number of zombie cells increases in your body, they become a living nightmare. Why? Zombie cells accelerate aging because they cause the earlier development of many chronic diseases. In this study they found that zombie cells in the animals began to appear while they were on a ketogenic diet. The zombie cells then disappeared when researchers changed the diet to a “non-ketogenic diet” (i.e., the Zone diet). And when the animals were given a Keto diet again, the zombie cells reappeared. Notice a trend? If you want to hear more about this study you can listen to our recent podcast at Dr.Sears.com. Based on earlier blogs, this adds to the list of downsides for following a ketogenic diet versus the Zone Diet. PROS Rapid initial weight loss: This is primarily due to the loss of retained water from the glycogen stores in the liver, which is rapidly used up to maintain blood sugar levels. Since these glycogen stores in the liver contain significant levels of retained water, much of the initial weight loss is water rather than stored body fat. If your main goal is loss retained water, this can be seen as a benefit. Of course, going to a sauna would also work. Reduced hunger: Ketogenic diets are rich in protein. Any increase in protein intake can help reduce hunger. CONS Production of acetone: One of the ketone bodies produced during ketosis is acetone, which is also the main chemical in nail polish. Increased calcium loss: A ketogenic diet can lead to higher calcium loss from bones. Limited fat utilization: High levels of dietary fat reduce the likelihood of using stored body fat for energy unless you also significantly restrict calories. Reduced energy levels: The lack of ATP production on a ketogenic diet can lead to easier fatigue during mild exercise. Damage from cheat meals: After seven days on a keto diet, a single high-carb cheat meal can damage blood vessels. Lack of polyphenols: This makes it difficult to activate genes that optimize metabolism by improving mitochondrial efficiency in converting fat into ATP. No long-term weight loss advantage: Long-term studies show no difference in weight loss between a ketogenic diet and a low-fat, high-carb diet. No short-term metabolic advantage: Careful studies demonstrate that fat loss on a ketogenic diet is the same as on a low-fat, high-carb diet with the same caloric intake. Compromised gut health: A lack of fermentable fiber from carbohydrates can lead to poor gut health and an increased risk of developing a leaky gut, which can cause significant inflammation. Furthermore, short-chain fatty acids (SCFA) are the metabolic product of fermentable fiber. These SCFA are powerful epigenetic signaling agents that enhance gene transcription. Ketosis generates a different type of hydroxylated short fatty acid (3-hydroxyl butyrate, that has no effect on gene transcription. In addition, the lack of SCFA has significant negative consequences on the gut-brain axis. Cortisol build-up: To produce glucose for the brain, cortisol levels increase to breakdown protein to make sufficient glucose via neoglucogenesis. Excess cortisol can lead to insulin resistance that cause regain of some of initially loss body fat. In addition, increased cortisol levels cause a depressed immune system as well as destruction of memory cells in the hippocampus. The initial benefits of following the ketogenic diet result in some initial weight loss (primarily water weight rather than fat loss), long-term studies show no significant differences in overall weight loss. Now new findings show a ketogenic diet may lead to significant adverse health consequences by accelerating the formation of zombie cells. Call me crazy, but I feel the key to longevity and wellness comes down to better metabolic control instead of living in a constant state of ketosis. Following Metabolic Engineering® for a lifetime provides that pathway of losing body fat without ketosis. References 1. 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 2006 83:1055-61. 2. White AM, Johnston CS, Swan PD, Tjonn SL, and Sears B. “Blood ketones are directly related to fatigue and perceived effort during exercise in overweight adults adhering to low-carbohydrate diets for weight loss: a pilot study.” J Am Diet Assoc. 2007 107:1792-1796. 3. Sung-Jen Wei, Joseph R Schell, E Sandra Chocron, Mahboubeh Varmazyad, Guogang Xu, Wan Hsi Chen, Gloria M Martinez, Felix F Dong, Prethish Sreenivas, Rolando Trevino Jr , Haiyan Jiang, Yan Du, Afaf Saliba, Wei Qian, Brandon Lorenzana, Alia Nazarullah, Jenny Chang, Kumar Sharma, Erin Munkácsy, Nobuo Horikoshi, David Gius. Ketogenic diet induces p53-dependent cellular senescence in multiple organs. Sci Adv. 2024 May 17;10(20):eado1463. doi: 10.1126/sciadv.ado1463. 4. Owen OE, Felig P, Morgan AP, Wahren J, Cahill GF Jr. Liver and kidney metabolism during prolonged starvation. J Clin Invest. 1969 Mar;48(3):574-83. doi: 10.1172/JCI106016. 5. Chriett, S., Dąbek, A., Wojtala, M. et al. Prominent action of butyrate over β-hydroxybutyrate as histone deacetylase inhibitor, transcriptional modulator and anti-inflammatory molecule. Sci Rep 9, 742 (2019). https://doi.org/10.1038/s41598-018-36941-9. 6. Silva YP, Bernardi A, Frozza RL. The Role of Short-Chain Fatty Acids From Gut Microbiota in Gut-Brain Communication. Front Endocrinol (Lausanne). 2020 Jan 31;11:25. doi: 10.3389/fendo.2020.00025. 

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050824---Tofu-Blog

Tofu: Tips and Recipes Ideas

I have been eating tofu for a very long time, much longer than the 30 or so years I have been following the Zone Diet. Back then many of my favorite recipes came from the Tassajara cookbooks by Edward Espe Brown, the celebrated chef from the kitchen at California’s famous Zen Mountain Center, and cookbooks by Louise Hagler, a.k.a. Wendy Louise, a well-known authority on vegetarian cooking who is associated with a community in Tennessee known as The Farm. Those books are still among the best resources for tofu recipes. My mantra has always been if you don’t like something, don’t eat it. Keep this in mind if you’re new to tofu, start slowly by combining it with flavors and foods you like.    Tips and Suggestions    Firm-sprouted tofu is my preference for the Zone Diet. Unlike traditional tofu, which contains significant amounts of both protein and carbohydrate, sprouted has almost no carbohydrates. It’s lighter tasting, refreshing, and very filling.   Freezing tofu results in a chewy, sponge-like texture. I don’t recommend freezing, but some people prefer it when using tofu to substitute for meat in a recipe.    Baked tofu comes in a variety of flavors and makes an excellent quick meal with some vegetables and fruit added. It’s also great in salads.     Tofu made it into the book “The Top 100 Zone Foods” by Barry Sears.    Some recipes call for draining the tofu first. I find that usually isn’t necessary.   Tofu takes on the flavor of whatever is added to it.    Add nutritional yeast flakes to give a cheesy flavor to vegan tofu scrambles and dips. It’s also rich in protein and vitamin B12.   Cherry Vanilla Tofu “Ice Cream”   Tip: This doesn’t freeze or store well, so prepare only the amount you plan to serve immediately.   Using an immersion blender or a food processor blend equal parts of frozen dark cherries and firm tofu, plus some vanilla extract (preferably alcohol-free for best flavor). Serve immediately.  Tofu Scramble  This is great for breakfast, lunch, or dinner, and we’ve even brought it on long day hikes for a snack.   Crumble some firm tofu and stir in a generous amount of seasonings, taking care not to overdo it with the salt. Heat in a well-seasoned or nonstick skillet with a little Zone-friendly oil to the desired doneness.    Optional: If time allows, sauté some chopped onion in the skillet before adding the tofu and seasonings.    My favorite seasoning combination for this dish at my house is onion powder, garlic powder, turmeric, paprika, some oregano or thyme, nutritional yeast flakes, salt, and ground black pepper. The yellow color of the turmeric makes it somewhat like scrambled eggs.   Tofu Veggie Almond Pasta Salad   Dressing: Thin some smooth almond butter by stirring in some water, a little vinegar, and either soy sauce or Bragg’s Liquid Aminos (an unfermented soy sauce found in the health food section of most grocery stores).    Toss together cooked Dr. Sears’ Zone PastaRx Fusilli, tofu cut into cubes, matchstick cut red bell pepper, chopped green parts of scallions (a.k.a. green onions), and the almond butter dressing. Serve immediately or chill to serve later. It will keep well in the fridge for two or three days.   Use your imagination and see what you can come up with.  Experiment and have fun with it. Try using tofu to make cheesecakes, whipped desserts, tofu chocolate pudding, tofu “cream” based soups, tofu pot pie (think chicken pot pie), tofu burgers, tofu burritos, Buffalo tofu (like Buffalo wings), layered Mediterranean dips, tofu “meatballs”, grilled tofu, and more.    Enjoy! 

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