Omega-6 / omega-3 ratio 7. August 2008 William Davis (11) Most of us already know that the intake of omega-6 fatty acids in the American diet has gone overboard, much at the expense of the omega-3 fraction. This occurred as a result of the misguided advice of the 1970s and 1980s to eat polyunsaturated oils like corn, sunflower, and safflower, because of their presumed cholesterol-reducing properties compared to saturated fats. However, more recent examinations of this advice have suggested that the omega-6 fraction of oils present in polyunsaturated oils may amplify arachidonic acid and other inflammatory patterns despite the reduction in cholesterol (total and LDL). Dr. Artemis Simopoulos of the Center for Genetics, Nutrition and Health in Washington, D.C. has written extensively on the role of omega-6 and omega-3 fatty acids in diet. In a review entitled The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cadiovacular Disease and Other Chronic Disease , Dr. Simopoulos collects the following comparison of omega-6 to omega-3 ratios from various populations: Paleolithic humans 0.79Greece (prior to 1960) 1.00-2.00Current Japan 4.00Current India, rural 5-6.1Current United Kindom and northern Europe 15.00Current United States 16.74Current India, urban 38-50(The numbers refer to the ratio of omega-6 to omega-3 intake.)If we believe the observations of Dr. Loren Cordain and others, while paleolithic man died of trauma and infectious diseases, they did not die of heart disease. Paleolithic human intake of omega-3 exceeded that of omega-6. Likewise, the traditionally low cardiac event regions of the world like Japan and Greece have less omega-3 intake than Paleolithic man, but still many times more than the U.S. and U.K. Worst of all with an enormous preponderance of omega-6 over omega-3 are urban Indians, who experience among the highest rates of heart disease in the world. Just for perspective, let's assume you eat an 1800 calorie per day diet, of which 30% of calories come from fat. This would amount to 540 calories per day from fat. With 9 calories per gram of fat, this means that there are 60 grams, or 60,000 mg, of fat in your diet per day. Paleolithic man has been found to have existed on a diet consisting of 21% of calories from fats. Again assuming an 1800 calorie per day diet, that comes to 42 grams of fat per day (42,000 mg). If we were to try to recreate the Paleolithic fat composition of diet, we would ingest 21,000 mg of omega-3 fatty acids (EPA, DHA, linolenic acid) per day. Even recreating a Japanese experience with a 4:1 ratio, it would mean 8400 mg of omega-3 per day. (Curiously, this does not agree with all estimates of Japanese intake of omega-3s.)No matter how you look at it, cultures with lower rates of cardiovascular disease take in greater--much greater--quantities of omega-3 fatty acids. So don't complain about your six fish oil capsules (usually containing 6000 mg of total oil, 1800 mg omega-3s)!
Dr. Bernadine Healy on heart scans 5. August 2008 William Davis (1) A Heart Scan Blog reader brought the following tidbit to my attention. Cardiologist and now writer for U.S. News and World Report, Dr. Bernadine Healy, wrote this editorial, a glowing endorsement of heart scans: The approach is beautifully simple. Calcium accumulates in advanced plaques, so calcium visible in the heart's arteries indicates atherosclerosis. An exploding number of studies in the past few years have unequivocally shown that the calcium score predicts both heart attack and sudden death. As a generalization, patients with scores between 100 and 400 face three to four times the risk of a heart attack or death compared with others at the same age with a zero score. Over 400, that elevated risk more than doubles.Most doctors rely instead on the Framingham calculator, which estimates a symptom-free person's risk of a heart attack in the next 10 years based on smoking history, blood pressure, cholesterol levels, sex, and age. It's available free online from the National Institutes of Health. Most people taking the test will have minimal or no coronary disease, though risk estimates over 9 percent should inspire vigorous preventive efforts. For some, however, coronary heart disease is sneaky, and Framingham will underestimate what lies ahead. Roughly half of those who suffer a major heart attack or sudden coronary death are symptom free. Calcium scores are additive to Framingham; they pick up the individual surprises by using X-ray vision to look inside the heart. No wonder insurance companies are scrambling to use coronary calcium scores—life insurers, that is.Dr. Bernadine Healy is no small-time player. In addition to her academic credentials, she is former chief of the National Institutes of Health (the first woman to hold the influential post), former head of the American Red Cross, and former deputy director of the White House Office of Science and Technology Policy under the Reagan administration. An endorsement of CT heart scans, though written under the guise of a probing editorial, will do an enormous amount of good to overcome the hurdles in gaining wider acceptance of heart scans.Those of us applying heart scans in everyday practice have long appreciated their enormous power to detect and track coronary plaque. Framingham scoring can't even touch the certainty and quantification provided by heart scans in day-to-day life. Hundreds of studies have validated their use, but they still suffer from lying in the shadows of the procedural bullies aiming to boost the number of heart catheterizations, angioplasties, stents, bypass surgeries. Dr. Healy, a voice with great weight, not just a political figure but also a cardiologist and scientist, has done a great service to broadcast the message of heart scanning.
Mercury and fish oil 2. August 2008 William Davis (9) As time passes, the dose of fish oil advocated in the Track Your Plaque program is going upward. While epidemiologic studies, like the Chicago Western Electric Study and the Nurses' Health Study suggest that decreases in mortality from heart disease begin by just eating fish a couple times per month, there are newer data that suggest greater quantities confer greater benefits. In the last Heart Scan Blog post, I discussed the recently-released ERA JUMP Study that demonstrated a relationship between higher omega-3 fatty acid blood content and reduced quantities of carotid and coronary plaque. The JELIS Study demonstrated a 19% reduction in cardiovascular events when fish-consuming Japanese added 1800 mg of EPA (only). However, the suggestion that increased quantities of fish oil potentially yield greater protection from heart attack and facilitate coronary plaque regression is also stirring up worries about mercury exposure. So I dug up a Heart Scan Blog post from a year ago that discussed this issue and reprint it here. I often get questions about the mercury content in fish oil. I've even had patients come to the office saying their primary care doctor told them to stop fish oil to avoid mercury poisoning. Manufacturers of fish oil also make claims that this product or that ("super-concentrated", "pharmaceutical grade", "purified", etc.) is purer or less contaminated than competitors' products. The manufacturers of the "drug" Omacor [now Lovaza], or prescription fish oil, have added to the confusion by suggesting that their product is the most pure of all, since it is the most concentrated of any fish oil preparation (900 mg EPA+DHA per capsule). They claim that "OMACOR is naturally derived through a unique, patented process that creates a highly concentrated, highly purified prescription medicine. By prescribing OMACOR® (omega-3-acid ethyl esters), a prescription omega-3, your doctor is giving you a concentrated and reliable omega-3. Each OMACOR capsule contains 90% omega-3 acids (84% EPA/DHA*). Nonprescription omega-3 dietary supplements typically contain only 13%-63% EPA/DHA." How much truth is there in these concerns?Let's go to the data published by the USDA, FDA, and several independent studies. Let's add to that the independent (and therefore presumably unbiased) analyses provided by Consumer Reports and Consumer Labs (www.consumerlab.com). How much mercury has been found in fish oil supplements?None.This is different from the mercury content of whole fish that you eat. Predatory fish that are at the top of the food chain and consume other fish and thereby concentrate organic methyl mercury, the toxic form of mercury. Thus, shark, swordfish, and King mackerel are higher in mercury than sardines, herring, and salmon. The mercury content of fish oil capsules have little to do with the method of processing and much more with the animal source of oil. Fish oil is generally obtained from sardines, salmon, and cod, all low in mercury. Fish oil capsules are not prepared from swordfish or shark. Thus, concerns about mercury from fish oil--regardless of brand--are generally unfounded, according to the best information we have. Eating whole fish--now that's another story for another time. But you and I can take our fish oil to reduce triglycerides, VLDL, IDL, small LDL, and heart attack risk without worrying about mercury.I am not advocating ad libitum eating of fish. Sadly, this may be related to excessive accumulation of contaminants. I am suggesting that greater quantities of omega-3 fatty acids from relatively contaminant- and mercury-free fish oil capsules. More on this in an upcoming webinar on the Track Your Plaque website: Fish Oil and the Track Your Plaque Program - Is More Better?
ERA JUMP: Omega-3 fatty acids and plaque 1. August 2008 William Davis (5) The results of the uniquely-constructed ERA JUMP Study were just released, a fascinating study of the relationship of omega-3 fatty acids to coronary and carotid plaque.The study adds insight into why the Japanese experience only one third of the heart attacks of Americans, and why Japan occupies the bottom of the list for least heart attacks among all developed countries. The Electron-Beam Tomography, Risk Factor Assessment Among Japanese and U.S. Men in the Post-World War II Birth Cohort Study (ERA JUMP), a collaborative U.S.-Japanese effort, compared three groups of men: -- 281 Japanese men living in Japan-- 306 non-Japanese men living in the U.S. (Pittsburgh, Pennsylvania)-- 303 Japanese Americans (having both parents Japanese without “ethnic admixture”) living in Hawaii. The last group represents a group that is genetically similar to the group in Japan, but exposed to an American diet and lifestyle. Three main measures were compared: -- Blood levels of omega-3 fatty acids, EPA and DHA)-- Carotid intimal-medial thickness (CIMT, the thickness of the carotid artery lining that can serve as an index of body-wide atherosclerosis)-- Coronary calcium (heart scan) scores. Interestingly, at the start of the study, the Japanese men possessed an overall cardiovascular risk profile worse than the Americans: Though more slender (BMI 23.6), Japanese men were more likely to be smokers, alcohol drinkers, had more high blood pressure, and were less likely to take cholesterol medications. The Americans, conversely, although heavier (BMI 27.9), were less likely to be smokers and drinkers, and had a four-fold greater use of cholesterol medications. The Japanese Americans were the most likely to be hypertensive, diabetic, with a similar proportion of overweight as the non-Japanese Americans. Despite the overall greater heart disease risk for profile for Japanese men, compared to non-Japanese Americans they had 10% less CIMT. In addition, only 9.3% of Japanese men had abnormal coronary calcium scores vs. 26.1% of non-Japanese Americans. Japanese-Americans were the worst, however, with nearly 10% more CIMT than non-Japanese Americans and 31.4% with abnormal calcium scores. The most intriguing finding of all was the fact that, of all the various groups and degrees of atherosclerosis, whether gauged via CIMT or coronary calcium scores, the blood level of omega-3 fatty acids was inversely related, i.e., the greater the omega-3 blood level, the less plaque by either measure was detected. Japanese men had the highest omega-3 blood levels: twice that of the non-Japanese Americans. The Japanese-Americans had levels only slightly greater than non-Japanese Americans. While other studies, like the GISSI Prevenzione study, have persuasively demonstrated that omega-3 fatty acids substantially reduce heart attack, a weak link in the omega-3 argument has been a study that links greater omega-3 intake with less atherosclerosis. The unique construction of the ERA JUMP Study, employing two groups with sharply different omega-3 intakes, very powerfully argues for the plaque-inhibiting effects of this fraction of fats. How much omega-3 fatty acids do Japanese people eat? Estimates vary, depending on part of the country, coastal vs. inland, age, etc., but Japanese tend to ingest anywhere from 5 to 15-times more omega-3 fatty acids than Americans. The actual intake of omega-3 fatty acids (EPA +DHA) in Japanese ranges from 850 to 3100 mg per day.
Mediterranean diet and blood sugar 31. July 2008 William Davis Toggle navigation Home Blog Home Archive Join Now Regular Site Log in You just THINK you're low-carb 27. ፌብሩወሪ 2010 William Davis (72) Systematically checking postprandial (after-eating) blood sugars is providing some great insights into crafting a better diet for many people. I last discussed the concept of postprandial glucose checks in To get low-carb right, you need to check blood sugars.Here are some important lessons that many people--NON-diabetic people, most with normal blood glucoses or just mildly increased--are learning:Oatmeal yields high blood sugars. Even if your fasting blood sugar is 90 mg/dl, a bowl of oatmeal with skim milk, walnuts, and some berries will yield blood sugars of 150-200 mg/dl in many people. Cheerios yields shocking blood sugars. 200+ mg/dl is not uncommon in non-diabetics. (Diabetics have 250-350 mg/dl.) Fruits like apples and bananas increase blood sugar to 130 mg/dl or higher. Odd symptoms, such as mental "fog," fatigue, and a fullness in the head, are often attributable to high blood sugars. A subset of people with lipoprotein(a) can have wildly increased blood sugars despite their slender build and high aerobic exercise habits. Once you identify the high blood sugar problem, you can do something about it. The best place to start is to reduce or eliminate the sugar-provoking food. The LDL-Fructose Disconnect 26. ፌብሩወሪ 2010 William Davis (8) I believe that we can all agree that the commonly obtained Friedewald LDL cholesterol (what I call "fictitious" LDL cholesterol) is wildly inaccurate. 100%--yes, 100% inaccuracy--is not at all uncommon.This flagrant inaccuracy, unacceptable in virtually every other discipline (imagine your airplane flight to New York lands in Pittsburgh--close enough, isn't it?), is highlighted in the University of California study by Stanhope et al I discussed previously.32 participants consumed either a diet enriched with either fructose or glucose. Compared to the effect of glucose, after 10 weeks fructose:Increased LDL cholesterol (calculated) by 7.6%Increased Apoprotein B (a measure of the number of LDL particles) by 24%Increased small dense LDL by 41%Increased oxidized LDL by 12.6% In other words, conventional calculated LDL substantially underestimates the undesirable effects of fructose. The divergence between calculated LDL and small LDL is especially dramatic. (By the way, this same divergence applies to the studies suggesting that calculated LDL cholesterol is reduced by low fat diets--While calculated LDL may indeed be reduced, small LDL goes way up, a striking divergence.) This is yet another reason to not rely on this "fictitious" LDL cholesterol value that, inaccuracies notwithstanding, serves as the foundation for a $27 billion per year industry. I told you bread was bad 26. ፌብሩወሪ 2010 William Davis (10) "I dream about bread" 25. ፌብሩወሪ 2010 William Davis (14) Marion sat in my office, sobbing. It had been 4 weeks since the last piece of bread, bagel, or bun had passed her lips. "I can't do it! I just can't do it! I've tried to eliminate wheat, but it's making me crazy. I'm having dreams about bread!"Yes, Timmy, such dark corners of human behavior are truly unveiled by removing wheat from the diet. (See the previous Heart Scan Blog post, Wheat withdrawal.)This is a real phenomenon: Wheat is the crack cocaine of the masses. Maybe you don't exchange $100 bills in dark corners of an inner city crack house, but I'll bet you paid $3.99 for your latest fix of French bread. Just in the last 2 weeks, people in my office who have eliminated wheat have experienced:14 lbs weight loss in 14 daysIncreased mental clarity, reduced moodiness, deeper sleep70% reductions in small LDL More than 300 mg/dl reductions in triglyceridesRelief from chronic scalp rashI could go on. All the while, the USDA, the American Heart Association, the American Diabetes Association, the American Dietetic Association, the Surgeon General's Office all advise you to eat more "healthy whole grains." 70% of people (NOT 100%, but the majority) will experience unexpected health benefits by eliminating this corrupt, unphysiologic product called wheat from their diet. You won't know until you try. Prototypical Lipoprotein(a) 25. ፌብሩወሪ 2010 William Davis (23) Here's the prototypical male with lipoprotein(a):Several features stand out in the majority of men with lipoprotein(a), Lp(a):Slender--Sometimes absurdly so: BMIs of 21-23 are not uncommon. These are the people who claim they can't gain weight. Intelligent--Above average to way above average intelligence is the rule. Gravitate to technical work--Plenty of engineers, scientists, accountants, and other people who work with numbers and/or technical details are more likely to have Lp(a). Enjoy high levels of aerobic performance--I tell my Lp(a) patients that, if they want to see a bunch of other people with Lp(a), go to a marathon or triathlon. They'll see plenty of people with the pattern among the aerobically-elite. Are rabid fans of Star Trek. Okay, I made the last one up. But the rest are uncannilly true, shared by the majority (though not all) men with Lp(a). Why? I can only speculate that the gene(s) for Lp(a) are closely linked to gene(s) for intelligence of a quantitative kind and some factor that enhances aerobic performance or yields a desirable emotional state with exercise. Oddly, the same patterns tend not to occur in women in Lp(a). I have yet to discern a personality or body configuration phenotype among the ladies. Gastric emptying: When slower is better 20. ፌብሩወሪ 2010 William Davis (18) When it comes to the Internet and Nascar, speed is good: The faster the better. But when it comes to gastric emptying (the rate at which food passes from the stomach and into the duodenum and small intestine), slower can be better. Slower transit time for foods passing through the stomach leads to lower blood sugar, lower blood glucose area under-the-curve (AUC), i.e., reduced blood glucose levels over time. Lower postprandial (after-eating) blood sugars can reduce cardiovascular risk. It can lead to a reduction in net calorie intake and weight loss. Strategies that can slow gastric emptying include:--Minimizing fluids during a meal--Drinking a lot of fluids, e.g., water, accelerates gastric emptying by approximately 20%. --Cinnamon--While the full reason to explain Cassia cinnamon's blood glucose-reducing effect has not been completely worked out, part of the effect is likely to due slowed gastric emptying. Thus, a 1/4-2 teaspoons of cinnamon per day can reduce postprandial blood sugar peaks by 10-25 mg/dl. --Vinegar--Two teaspoons of vinegar in its various forms slows gastric emptying. The effect is likely due to acetic acid, the compound shared by apple cider vinegar, white vinegar, red wine vinegar, Balsamic vinegar, and other varieties. --Increased fat content--Fat is digested more slowly and slows gastric emptying time, compared to the rapid transit of carbohydrates. Not everybody should slow gastric emptying. Diabetics with a condition called diabetic gastroparesis should not use these methods, as they can further slow the abnormal gastric emptying that develops as part of their disease, making a bad situation worse. However, in the rest of us with normal gastric emptying time, a delay in gastric emptying can reduce blood sugar and induce satiety, effects that can work in your favor in reducing cardiovascular risk. Genetic vs. lifestyle small LDL 19. ፌብሩወሪ 2010 William Davis (59) Let me explain what I mean by "genetic small LDL." I think it helps to illustrate with two common examples. Ollie is 50 years old, 5 ft 10 inches tall, and weighs 253 lbs. BMI = 36.4 (obese). Starting lipoproteins (NMR):LDL particle number 2310 nmol/LSmall LDL: 1893 nmol/L (1893/2310 = 81.9% of total, a severe small LDL pattern)Stan is 50 years old, also, 5 ft 10 inches tall, and weighs 148 lbs. BMI = 21.3. Starting lipoproteins:LDL particle number 1424 nmol/LSmall LDL 1288 nmol/L (1288/1424 = 90.4% of total, also severe)Both Ollie and Stan go on the New Track Your Plaque diet and eliminate wheat, cornstarch, and sugars, while increasing oils, meats and fish, unlimited raw nuts, and vegetables. They add fish oil and vitamin D and achieve perfect levels of both. Six months later, Ollie has lost 55 lbs, Stan has lost 4 lbs. A second round of lipoproteins:Ollie:LDL particle number 1810 nmol/LSmall LDL: 193 nmol/L (193/1810 = 10.6% of total)Stan:LDL particle number 1113 nmol/LSmall LDL 729 nmool/L (729/1113 = 65.4% of total)Ollie has reduced, nearly eliminated, small LDL through elimination of wheat, cornstarch, and sugars, along with weight loss, fish oil, and vitamin D. Stan, beginning at a much more favorable weight, reduced both total and small LDL with the same efforts, but retains a substantial proportion (65.4%) of small LDL. Stan's pattern is what I call "genetic small LDL." Of course, this is a presumptive designation, since we've not identified the specific gene(s) that allow this (e.g., gene for variants of cholesteryl ester transfer protein, hepatic lipase, lipoprotein lipase, and others). But it is such a sharp distinction that I am convinced that people like Stan have this persistent pattern as a genetically-determined trait. Carbohydrate sins of the past 17. ፌብሩወሪ 2010 William Davis (15) Fifty years ago, diabetes was a relatively uncommon disease. Today, the latest estimates are that 50% of Americans are now diabetic or pre-diabetic. There are some obvious explanations: excess weight, inactivity, the proliferation of fructose in our diets. It is also my firm belief that the diets advocated by official agencies, like the USDA, the American Heart Association, the American Dietetic Association, and the American Diabetes Association, have also contributed with their advice to eat more “healthy whole grains.” When I was a kid, I ate Lucky Charms® or Cocoa Puffs® for breakfast, carried Hoho’s® and Scooter Pies® in my lunchbox, along with a peanut butter sandwich on white bread. We ate TV dinners, biscuits, instant mashed potatoes for dinner. Back then, it was a matter of novelty, convenience, and, yes, taste. What did we do to our pancreases eating such insulin-stimulating foods through childhood, teenage years, and into early adulthood? Did our eating habits as children and young adults create diabetes many years later? Could sugary breakfast cereals, snacks, and candy in virtually unlimited quantities have impaired our pancreas’ ability to produce insulin, leading to pre-diabetes and diabetes many years later? A phenomenon called glucose toxicity underlies the development of diabetes and pre-diabetes. Glucose toxicity refers to the damaging effect that high blood sugars (glucose) have on the delicate beta cells of the pancreas, the cells that produce insulin. This damage isirreversible: once it occurs, it cannot be undone, and the beta cells stop producing insulin and die. The destructive effect of high glucose levels on pancreatic beta cells likely occurs through oxidative damage, with injury from toxic oxidative compounds like superoxide anion and peroxide. The pancreas is uniquely ill-equipped to resist oxidative injury, lacking little more than rudimentary anti-oxidative protection mechanisms. Glucose toxicity that occurs over many years eventually leaves you with a pancreas that retains only 50% or less of its original insulin producing capacity. That’s when diabetes develops, when impaired pancreatic insulin production can no longer keep up with the demands put on it. (Interesting but unanswered question: If oxidative injury leads to beta cell dysfunction and destruction, can antioxidants prevent such injury? Studies in cell preparations and animals suggest that anti-oxidative agents, such as astaxanthin and acetylcysteine, may block beta cell oxidative injury. However, no human studies have yet been performed. This may prove to be a fascinating area for future.)Now that 50% of American have diabetes or pre-diabetes, how much should we blame on eating habits when we were younger? I would wager that eating habits of youth play a large part in determining potential for diabetes or pre-diabetes as an adult. The lesson: Don’t allow children to repeat our mistakes. Letting them indulge in a lifestyle of soft drinks, candy, pretzels, and other processed junk carbohydrates has the potential to cause diabetes 20 or 30 years later, shortening their life by 10 years. Kids are not impervious to the effects of high sugar, including the cumulative damaging effects of glucose toxicity. Saturated fat and large LDL 16. ፌብሩወሪ 2010 William Davis (44) Here's a half-truth I often encounter in low-carb discussions:Saturated fat increases large LDL particlesFor those of you unfamiliar with the argument, I advocate a low-carbohydrate approach, specifically elimination of all wheat, cornstarch, and sugars, to reduce expression of the small LDL pattern (not to mention reduction of triglycerides, relief from acid reflux and irritable bowel, weight loss, various rashes, diabetes, etc). Small LDL particles have become the most common cause for heart disease in the U.S., exploding on the scene ever since agencies like the USDA and American Heart Association have been advising the public to increase consumption of "healthy whole grains." This has led some to make the pronouncement that saturated fat increases large LDL, thereby representing a benign effect. Is this true? It is true, but only partly. Let me explain. There are two general categories of factors causing small LDL particles: lifestyle (overweight, excess carbohydrates) and genetics (e.g., variants of the gene coding for cholesteryl-ester transfer protein, or CETP). If small LDL is purely driven by excess carbohydrates, then adding saturated fat will reduce small LDL and increase large LDL. If, on the other hand, your small LDL is genetically programmed, then saturated fat will increase small LDL. In other words, saturated fat tends to increase the dominant or genetically-determined form of LDL. If your dominant genetically-determined form is small, then saturated fat increases small LDL particles. So to say that saturated fat increases large LDL is an oversimplification, one that can have dire consequences in the wrong situation. Is glycemic index irrelevant? 14. ፌብሩወሪ 2010 William Davis (20) University of Toronto nutrition scientist, Dr. David Jenkins, was the first to quantify the phenomenon of "glycemic index," describing how much blood sugar increased over 90 minutes compared to glucose. The graph is from their 1981 study, The glycemic index of foods: a physiologic basis for carbohydrate exchange. The research originated with an effort to characterize carbohydrates for diabetics to gain better control over blood sugar.Since Dr. Jenkins’ original work, thousands of clinical studies have been performed by others exploring this concept. The food industry has also devoted plenty of effort exploiting it (e.g., low-glycemic index noodles, low-glycemic index cereals, etc.). Most Americans are now familiar with the concept of glycemic index. You likely know that table sugar has a high glycemic index (60), increasing blood sugar to a similar degree as white bread (glycemic index 71). Oatmeal (slow-cooked) has a lower glycemic index (48), since it increases blood sugar less than white bread. A number of studies have shown that when low glycemic index foods replace high glycemic index foods (e.g., whole wheat bread in place of cupcakes), people are healthier: less diabetes, less heart attack, less high blood pressure. Books have been written about glycemic index, touting its benefits for health and weight control. Health-conscious people will try to substitute low-glycemic index foods for high-glycemic index foods. So what’s not to like here? There are several fundamental flaws with the notion that low-glycemic index foods are good for you:1) Check your blood sugar after a low-glycemic index food like oatmeal. Most non-diabetic adults will show blood sugars in the 140 to 200 mg/dl range. The more central (visceral) fat you have, the higher the value will be. In other words, an apparently “healthy” whole grain food like oatmeal can generate extravagantly high blood sugars. Repeated high blood sugars of 125 mg/dl or greater after eating increase heart disease risk by 50%. 2) Foods like whole wheat pasta have a low glycemic index because the blood sugar effect over the usual 90 minutes is increased to a lesser degree. The problem is that it remains increased for an extended period of up to several hours. In other words, the blood sugar-increasing effect of pasta, even whole grain, is long and sustained. 3) Low-glycemic index foods trigger other abnormalities, such as small LDL particles, triglycerides, and c-reactive protein (a measure of inflammation). While they are not as bad as high-glycemic index foods, they are still quite potent triggers. Low-glycemic index foods trigger the very same responses as high-glycemic index foods—they’re just less bad. But less bad does not equate to good. Low-glycemic index foods cause weight gain, trigger appetite, increase blood pressure, and lead to the patterns that cause heart disease. High-glycemic index foods are bad for you. This includes foods made with white flour (bagels, white bread, pretzels). Low-glycemic foods (whole grain bread, whole wheat crackers, whole wheat pasta) are less bad for you—but they are not necessarily good. Don’t be falsely reassured by foods because they are billed as “low-glycemic index.” View low-glycemic index foods as indulgences, something you might have once in a while, since a slice of whole grain bread is really not that different from a icing-covered cupcake. << Older posts Newer posts >> Newer posts12...282930313233343536...123124Older posts
You just THINK you're low-carb 27. ፌብሩወሪ 2010 William Davis (72) Systematically checking postprandial (after-eating) blood sugars is providing some great insights into crafting a better diet for many people. I last discussed the concept of postprandial glucose checks in To get low-carb right, you need to check blood sugars.Here are some important lessons that many people--NON-diabetic people, most with normal blood glucoses or just mildly increased--are learning:Oatmeal yields high blood sugars. Even if your fasting blood sugar is 90 mg/dl, a bowl of oatmeal with skim milk, walnuts, and some berries will yield blood sugars of 150-200 mg/dl in many people. Cheerios yields shocking blood sugars. 200+ mg/dl is not uncommon in non-diabetics. (Diabetics have 250-350 mg/dl.) Fruits like apples and bananas increase blood sugar to 130 mg/dl or higher. Odd symptoms, such as mental "fog," fatigue, and a fullness in the head, are often attributable to high blood sugars. A subset of people with lipoprotein(a) can have wildly increased blood sugars despite their slender build and high aerobic exercise habits. Once you identify the high blood sugar problem, you can do something about it. The best place to start is to reduce or eliminate the sugar-provoking food.
The LDL-Fructose Disconnect 26. ፌብሩወሪ 2010 William Davis (8) I believe that we can all agree that the commonly obtained Friedewald LDL cholesterol (what I call "fictitious" LDL cholesterol) is wildly inaccurate. 100%--yes, 100% inaccuracy--is not at all uncommon.This flagrant inaccuracy, unacceptable in virtually every other discipline (imagine your airplane flight to New York lands in Pittsburgh--close enough, isn't it?), is highlighted in the University of California study by Stanhope et al I discussed previously.32 participants consumed either a diet enriched with either fructose or glucose. Compared to the effect of glucose, after 10 weeks fructose:Increased LDL cholesterol (calculated) by 7.6%Increased Apoprotein B (a measure of the number of LDL particles) by 24%Increased small dense LDL by 41%Increased oxidized LDL by 12.6% In other words, conventional calculated LDL substantially underestimates the undesirable effects of fructose. The divergence between calculated LDL and small LDL is especially dramatic. (By the way, this same divergence applies to the studies suggesting that calculated LDL cholesterol is reduced by low fat diets--While calculated LDL may indeed be reduced, small LDL goes way up, a striking divergence.) This is yet another reason to not rely on this "fictitious" LDL cholesterol value that, inaccuracies notwithstanding, serves as the foundation for a $27 billion per year industry.
"I dream about bread" 25. ፌብሩወሪ 2010 William Davis (14) Marion sat in my office, sobbing. It had been 4 weeks since the last piece of bread, bagel, or bun had passed her lips. "I can't do it! I just can't do it! I've tried to eliminate wheat, but it's making me crazy. I'm having dreams about bread!"Yes, Timmy, such dark corners of human behavior are truly unveiled by removing wheat from the diet. (See the previous Heart Scan Blog post, Wheat withdrawal.)This is a real phenomenon: Wheat is the crack cocaine of the masses. Maybe you don't exchange $100 bills in dark corners of an inner city crack house, but I'll bet you paid $3.99 for your latest fix of French bread. Just in the last 2 weeks, people in my office who have eliminated wheat have experienced:14 lbs weight loss in 14 daysIncreased mental clarity, reduced moodiness, deeper sleep70% reductions in small LDL More than 300 mg/dl reductions in triglyceridesRelief from chronic scalp rashI could go on. All the while, the USDA, the American Heart Association, the American Diabetes Association, the American Dietetic Association, the Surgeon General's Office all advise you to eat more "healthy whole grains." 70% of people (NOT 100%, but the majority) will experience unexpected health benefits by eliminating this corrupt, unphysiologic product called wheat from their diet. You won't know until you try.
Prototypical Lipoprotein(a) 25. ፌብሩወሪ 2010 William Davis (23) Here's the prototypical male with lipoprotein(a):Several features stand out in the majority of men with lipoprotein(a), Lp(a):Slender--Sometimes absurdly so: BMIs of 21-23 are not uncommon. These are the people who claim they can't gain weight. Intelligent--Above average to way above average intelligence is the rule. Gravitate to technical work--Plenty of engineers, scientists, accountants, and other people who work with numbers and/or technical details are more likely to have Lp(a). Enjoy high levels of aerobic performance--I tell my Lp(a) patients that, if they want to see a bunch of other people with Lp(a), go to a marathon or triathlon. They'll see plenty of people with the pattern among the aerobically-elite. Are rabid fans of Star Trek. Okay, I made the last one up. But the rest are uncannilly true, shared by the majority (though not all) men with Lp(a). Why? I can only speculate that the gene(s) for Lp(a) are closely linked to gene(s) for intelligence of a quantitative kind and some factor that enhances aerobic performance or yields a desirable emotional state with exercise. Oddly, the same patterns tend not to occur in women in Lp(a). I have yet to discern a personality or body configuration phenotype among the ladies.
Gastric emptying: When slower is better 20. ፌብሩወሪ 2010 William Davis (18) When it comes to the Internet and Nascar, speed is good: The faster the better. But when it comes to gastric emptying (the rate at which food passes from the stomach and into the duodenum and small intestine), slower can be better. Slower transit time for foods passing through the stomach leads to lower blood sugar, lower blood glucose area under-the-curve (AUC), i.e., reduced blood glucose levels over time. Lower postprandial (after-eating) blood sugars can reduce cardiovascular risk. It can lead to a reduction in net calorie intake and weight loss. Strategies that can slow gastric emptying include:--Minimizing fluids during a meal--Drinking a lot of fluids, e.g., water, accelerates gastric emptying by approximately 20%. --Cinnamon--While the full reason to explain Cassia cinnamon's blood glucose-reducing effect has not been completely worked out, part of the effect is likely to due slowed gastric emptying. Thus, a 1/4-2 teaspoons of cinnamon per day can reduce postprandial blood sugar peaks by 10-25 mg/dl. --Vinegar--Two teaspoons of vinegar in its various forms slows gastric emptying. The effect is likely due to acetic acid, the compound shared by apple cider vinegar, white vinegar, red wine vinegar, Balsamic vinegar, and other varieties. --Increased fat content--Fat is digested more slowly and slows gastric emptying time, compared to the rapid transit of carbohydrates. Not everybody should slow gastric emptying. Diabetics with a condition called diabetic gastroparesis should not use these methods, as they can further slow the abnormal gastric emptying that develops as part of their disease, making a bad situation worse. However, in the rest of us with normal gastric emptying time, a delay in gastric emptying can reduce blood sugar and induce satiety, effects that can work in your favor in reducing cardiovascular risk.
Genetic vs. lifestyle small LDL 19. ፌብሩወሪ 2010 William Davis (59) Let me explain what I mean by "genetic small LDL." I think it helps to illustrate with two common examples. Ollie is 50 years old, 5 ft 10 inches tall, and weighs 253 lbs. BMI = 36.4 (obese). Starting lipoproteins (NMR):LDL particle number 2310 nmol/LSmall LDL: 1893 nmol/L (1893/2310 = 81.9% of total, a severe small LDL pattern)Stan is 50 years old, also, 5 ft 10 inches tall, and weighs 148 lbs. BMI = 21.3. Starting lipoproteins:LDL particle number 1424 nmol/LSmall LDL 1288 nmol/L (1288/1424 = 90.4% of total, also severe)Both Ollie and Stan go on the New Track Your Plaque diet and eliminate wheat, cornstarch, and sugars, while increasing oils, meats and fish, unlimited raw nuts, and vegetables. They add fish oil and vitamin D and achieve perfect levels of both. Six months later, Ollie has lost 55 lbs, Stan has lost 4 lbs. A second round of lipoproteins:Ollie:LDL particle number 1810 nmol/LSmall LDL: 193 nmol/L (193/1810 = 10.6% of total)Stan:LDL particle number 1113 nmol/LSmall LDL 729 nmool/L (729/1113 = 65.4% of total)Ollie has reduced, nearly eliminated, small LDL through elimination of wheat, cornstarch, and sugars, along with weight loss, fish oil, and vitamin D. Stan, beginning at a much more favorable weight, reduced both total and small LDL with the same efforts, but retains a substantial proportion (65.4%) of small LDL. Stan's pattern is what I call "genetic small LDL." Of course, this is a presumptive designation, since we've not identified the specific gene(s) that allow this (e.g., gene for variants of cholesteryl ester transfer protein, hepatic lipase, lipoprotein lipase, and others). But it is such a sharp distinction that I am convinced that people like Stan have this persistent pattern as a genetically-determined trait.
Carbohydrate sins of the past 17. ፌብሩወሪ 2010 William Davis (15) Fifty years ago, diabetes was a relatively uncommon disease. Today, the latest estimates are that 50% of Americans are now diabetic or pre-diabetic. There are some obvious explanations: excess weight, inactivity, the proliferation of fructose in our diets. It is also my firm belief that the diets advocated by official agencies, like the USDA, the American Heart Association, the American Dietetic Association, and the American Diabetes Association, have also contributed with their advice to eat more “healthy whole grains.” When I was a kid, I ate Lucky Charms® or Cocoa Puffs® for breakfast, carried Hoho’s® and Scooter Pies® in my lunchbox, along with a peanut butter sandwich on white bread. We ate TV dinners, biscuits, instant mashed potatoes for dinner. Back then, it was a matter of novelty, convenience, and, yes, taste. What did we do to our pancreases eating such insulin-stimulating foods through childhood, teenage years, and into early adulthood? Did our eating habits as children and young adults create diabetes many years later? Could sugary breakfast cereals, snacks, and candy in virtually unlimited quantities have impaired our pancreas’ ability to produce insulin, leading to pre-diabetes and diabetes many years later? A phenomenon called glucose toxicity underlies the development of diabetes and pre-diabetes. Glucose toxicity refers to the damaging effect that high blood sugars (glucose) have on the delicate beta cells of the pancreas, the cells that produce insulin. This damage isirreversible: once it occurs, it cannot be undone, and the beta cells stop producing insulin and die. The destructive effect of high glucose levels on pancreatic beta cells likely occurs through oxidative damage, with injury from toxic oxidative compounds like superoxide anion and peroxide. The pancreas is uniquely ill-equipped to resist oxidative injury, lacking little more than rudimentary anti-oxidative protection mechanisms. Glucose toxicity that occurs over many years eventually leaves you with a pancreas that retains only 50% or less of its original insulin producing capacity. That’s when diabetes develops, when impaired pancreatic insulin production can no longer keep up with the demands put on it. (Interesting but unanswered question: If oxidative injury leads to beta cell dysfunction and destruction, can antioxidants prevent such injury? Studies in cell preparations and animals suggest that anti-oxidative agents, such as astaxanthin and acetylcysteine, may block beta cell oxidative injury. However, no human studies have yet been performed. This may prove to be a fascinating area for future.)Now that 50% of American have diabetes or pre-diabetes, how much should we blame on eating habits when we were younger? I would wager that eating habits of youth play a large part in determining potential for diabetes or pre-diabetes as an adult. The lesson: Don’t allow children to repeat our mistakes. Letting them indulge in a lifestyle of soft drinks, candy, pretzels, and other processed junk carbohydrates has the potential to cause diabetes 20 or 30 years later, shortening their life by 10 years. Kids are not impervious to the effects of high sugar, including the cumulative damaging effects of glucose toxicity.
Saturated fat and large LDL 16. ፌብሩወሪ 2010 William Davis (44) Here's a half-truth I often encounter in low-carb discussions:Saturated fat increases large LDL particlesFor those of you unfamiliar with the argument, I advocate a low-carbohydrate approach, specifically elimination of all wheat, cornstarch, and sugars, to reduce expression of the small LDL pattern (not to mention reduction of triglycerides, relief from acid reflux and irritable bowel, weight loss, various rashes, diabetes, etc). Small LDL particles have become the most common cause for heart disease in the U.S., exploding on the scene ever since agencies like the USDA and American Heart Association have been advising the public to increase consumption of "healthy whole grains." This has led some to make the pronouncement that saturated fat increases large LDL, thereby representing a benign effect. Is this true? It is true, but only partly. Let me explain. There are two general categories of factors causing small LDL particles: lifestyle (overweight, excess carbohydrates) and genetics (e.g., variants of the gene coding for cholesteryl-ester transfer protein, or CETP). If small LDL is purely driven by excess carbohydrates, then adding saturated fat will reduce small LDL and increase large LDL. If, on the other hand, your small LDL is genetically programmed, then saturated fat will increase small LDL. In other words, saturated fat tends to increase the dominant or genetically-determined form of LDL. If your dominant genetically-determined form is small, then saturated fat increases small LDL particles. So to say that saturated fat increases large LDL is an oversimplification, one that can have dire consequences in the wrong situation.
Is glycemic index irrelevant? 14. ፌብሩወሪ 2010 William Davis (20) University of Toronto nutrition scientist, Dr. David Jenkins, was the first to quantify the phenomenon of "glycemic index," describing how much blood sugar increased over 90 minutes compared to glucose. The graph is from their 1981 study, The glycemic index of foods: a physiologic basis for carbohydrate exchange. The research originated with an effort to characterize carbohydrates for diabetics to gain better control over blood sugar.Since Dr. Jenkins’ original work, thousands of clinical studies have been performed by others exploring this concept. The food industry has also devoted plenty of effort exploiting it (e.g., low-glycemic index noodles, low-glycemic index cereals, etc.). Most Americans are now familiar with the concept of glycemic index. You likely know that table sugar has a high glycemic index (60), increasing blood sugar to a similar degree as white bread (glycemic index 71). Oatmeal (slow-cooked) has a lower glycemic index (48), since it increases blood sugar less than white bread. A number of studies have shown that when low glycemic index foods replace high glycemic index foods (e.g., whole wheat bread in place of cupcakes), people are healthier: less diabetes, less heart attack, less high blood pressure. Books have been written about glycemic index, touting its benefits for health and weight control. Health-conscious people will try to substitute low-glycemic index foods for high-glycemic index foods. So what’s not to like here? There are several fundamental flaws with the notion that low-glycemic index foods are good for you:1) Check your blood sugar after a low-glycemic index food like oatmeal. Most non-diabetic adults will show blood sugars in the 140 to 200 mg/dl range. The more central (visceral) fat you have, the higher the value will be. In other words, an apparently “healthy” whole grain food like oatmeal can generate extravagantly high blood sugars. Repeated high blood sugars of 125 mg/dl or greater after eating increase heart disease risk by 50%. 2) Foods like whole wheat pasta have a low glycemic index because the blood sugar effect over the usual 90 minutes is increased to a lesser degree. The problem is that it remains increased for an extended period of up to several hours. In other words, the blood sugar-increasing effect of pasta, even whole grain, is long and sustained. 3) Low-glycemic index foods trigger other abnormalities, such as small LDL particles, triglycerides, and c-reactive protein (a measure of inflammation). While they are not as bad as high-glycemic index foods, they are still quite potent triggers. Low-glycemic index foods trigger the very same responses as high-glycemic index foods—they’re just less bad. But less bad does not equate to good. Low-glycemic index foods cause weight gain, trigger appetite, increase blood pressure, and lead to the patterns that cause heart disease. High-glycemic index foods are bad for you. This includes foods made with white flour (bagels, white bread, pretzels). Low-glycemic foods (whole grain bread, whole wheat crackers, whole wheat pasta) are less bad for you—but they are not necessarily good. Don’t be falsely reassured by foods because they are billed as “low-glycemic index.” View low-glycemic index foods as indulgences, something you might have once in a while, since a slice of whole grain bread is really not that different from a icing-covered cupcake.