Thursday, January 27, 2011

Review of Good Calories Bad Calories

EXTREMELY MISLEADING. NOT A PANACEA FOR WESTERN DISEASES.

IN A NUTSHELL

An Eco-Atkins diet can give you all the advantages of the high-meat Atkins without increasing the risk of heart disease or cancer. In a study by Jenkins et al in 2009, a plant based, low carb diet (26% carbs) produced an extremely good lipid profile, outperforming a low fat diet (25% fat) and the traditional Atkins diet. And in a 26 year study by Fung et al in 2010, an Eco-Atkins diet with only 12% animal protein showed a 43% decrease in all cause mortality compared to a reduced carb diet with 18% animal protein controlled for other variables. (This is not some uncontrolled epidemiological study; it's the kind of study that can be used to establish cause and effect. The high-meat group actually ate slightly less omega-6 and refined carbs so there`s no reason to think something other than grain fed meat caused them to do poorly.)

Both high-meat Atkins and Eco-Atkins are good at producing short term weight loss and blood sugar control. But a long term study of patients on a high-meat diet by Fleming in 2000 showed a worsening of blood flow after one year with an overall 39.7% progression of coronary artery disease. And a study that lasted over 10 years by Sjogren et al in 2010 showed that elderly men eating a Mediterranean diet were 37% less likely to die of heart disease, while elderly men eating a high meat, carbohydrate restricted diet were 44% more likely to die of heart disease.

This book leaves many readers strongly convinced that meat and full fat dairy are the best replacements for refined carbs. But the evidence is mostly based on stories of individuals which tell us nothing about the average person; uncontrolled observational studies of other cultures with many confounding variables (such as genetic differences, calorie restriction, cholesterol lowering saponins, grass fed meat high in CLA and omega-3, absence of alcohol and tobacco, greater vitamin D, organic produce, higher exercise levels etc.); and clinical trials where people practicing low carb were also practicing calorie restriction which is totally misleading about the maintenance phase and about the long term risk of heart disease and cancer. A study in 2009 by Miller et al that compared three diets (Atkins, South Beach and Ornish) during weight maintenance showed Atkins produced less favorable results for lipids and flow-mediated vasodilatation than the other two.

People are different. In a study by Corella et al in 2010, when saturated fat intake was greater than 10% of calories in individuals carrying the APOE4 allele, the risk of heart disease was over 300% higher. About 25 to 30 percent of Americans carry this allele. But cholesterol skeptics have convinced many Americans with the APOE4 allele to try a high animal fat diet and it's giving them heart disease.

Taken together these six studies show that weight loss, fluffy LDL etc. are not protecting people from heart disease. The incomplete risk profile in studies used to promote a high-meat Atkins diet fail to accurately predict what will actually happen decades in the future. They are giving people a false sense of security.

Some people think Denise Minger's blog proves a high-meat diet is safe. But the Tuoli data that Denise makes a big deal about, can't tell us anything about health because it doesn't represent the way the people were eating all year long. The people are nomadic and eat different foods at different times of year and they were feasting to impress the visitors. And the Tuoli culture has confounding variables just like the examples in GCBC. And the fact that the protein deficient rural Chinese benefited from a small amount of animal protein doesn't mean that Americans who are already eating ten times as much animal protein as the rural Chinese need even more. There are places in China as well as the rest for world where high wheat consumption is not associated with heart disease. Denise' analysis does not distinguish between low glycemic index forms of wheat (like pasta cooked al dente) and high glycemic index forms of wheat (like white bread.)

WATCH OUT FOR CONFIRMATION BIAS

According to Wikipedia, "Confirmation bias refers to a type of selective thinking whereby one tends to notice and to look for what confirms one's beliefs, and to ignore, not look for, or undervalue the relevance of what contradicts one's beliefs."

For example, Mr. Taubes is nihilistic about any evidence against animal fat. To him, every study has a flaw, nothing is ever certain. But when it comes to uncontrolled observational studies of other cultures (evidence that's much weaker than the evidence he finds fault with), he accepts it without critical thinking.

"Confirmation biases contribute to overconfidence in personal beliefs and can maintain or strengthen beliefs in the face of contrary evidence. Hence they can lead to disastrous decisions, especially in organizational, military, political and social contexts."

"Individuals have to constantly remind themselves of this tendency and actively seek out data contrary to their beliefs." Since this isn't easy, most of the time we're stuck with bias. Nobody can be completely free of bias but we can make an effort. But we should always be biased in favor of studies published in peer reviewed journals over opinions published in books or on web sites. (Peer review attempts to find obvious errors and correct biased interpretations that go beyond the data.) And we should always value long term studies that measure disease more than short term studies that only measure risk factors.

For example, if Mr. Taubes had submitted his book to peer review, someone would have pointed out that the Masai are not a good argument for eating a high animal fat diet since they eat cholesterol lowering saponins and are believed to have genetic hypocholesterolemia.

FULL REVIEW

POINTS OF AGREEMENT

1) I agree that low carb is effective for diabetes and weight loss (but so are low fat, high fiber diets.)
2) I agree that high glycemic index carbs should be included in the long list of risk factors for heart disease (but animal fat is as least as bad and probably worse.)
3) I agree that total cholesterol below 150 is associated with a greater risk of stroke, but only for people with untreated hypertension or who smoke or drink alcohol or caffeine.

POINTS OF DISAGREEMENT

1) MISLEADING ABOUT THE DIET OF HUNTER GATHERERS : On page 69 of GCBC, Mr. Taubes cites a study by Loren Cordain et al that says hunter-gatherers ate 28% to 58% total fat. Taubes uses this study as evidence that all humans are adapted to a high saturated fat diet. But when you look at the details, Taubes completely misrepresents what Cordain believes. Here's what Cordain says about saturated fat, "The typical Paleolithic diet compared with the average modern American diet contained 2 to 3 times more fiber [from fruits and vegetables], 1.5 to 2.0 times more polyunsaturated and monounsaturated fats, 4 times more omega-3 fats, but 60% to 70% less saturated fat." This is in spite of the fact that they consumed the entire carcass of the animal. This is because they ate wild game (average of .89 grams saturated fat per serving) instead of grain fattened domestic animals (average of 7.04 grams saturated fat per serving). Grass fed meat also contains more CLA and omega-3 fatty acids which are associated with a reduced risk of heart disease and cancer.

2) MISLEADING ABOUT HEALTHY CARBS:  Beans have a low glycemic index and if eaten on a regular basis their fiber and resistant starch (depending on the variety) can lower fasting blood sugar, insulin, triglycerides and improve the HDL/total cholesterol ratio. Oats and barley contain beta glucan and resistant starch which can lower fasting blood sugar, insulin and improve the HDL/total cholesterol ratio. Insoluble fiber like wheat bran is very important for digestive health. For the small percentage of people with celiac disease (1%) or gluten sensitivity (3 - 15%) there are many grains without gluten. Cultures where people live the longest eat more whole grains, beans and yams than the average American.

Most people handle low glycemic index, high fiber carbs just fine (these include fruit, non-starchy vegetables, peas, beans, whole grain pasta cooked al dente, rolled oats, corn on the cob, brown rice, sprouted grain bread, yams etc.) They don't cause the metabolic syndrome or increase the number of small dense LDL particles. The American public has never tried replacing saturated animal fat, sugar, white flour and baking potatoes with low glycemic index, high fiber carbs, nuts, olive or canola oil and fish. And the average American is eating out more often (sometimes twice a day instead of twice a week) and getting bigger portions than we would at home. Therefore the obesity epidemic proves nothing about beans and peas and whole grains and yams.

On page 454 GCBC says "By stimulating insulin secretion, carbohydrates make us fat and ultimately cause obesity. The fewer carbohydrates we consume the leaner we will be." If there is even one exception then there is something wrong with the hypothesis. In rural China during the 80s, they ate 75.8% carbs (but they're healthy carbs) and more calories than Americans and they had extremely low rates of obesity, diabetes and heart disease. These facts about China are not in dispute. By ignoring them GCBC misleads us about the complexities of physiology and the fact that some people do best on low carb while many others do best on low fat.

3) MISLEADING ABOUT DIABETES : Following the diet recommended by the American Diabetes Association reduced HbA1c by 0.4 percentage points, but eating an ultra low fat diet with low glycemic index, high fiber carbs reduced HbA1c by 3 times that amount. This is a greater effect than taking a diabetic medication. (See [[ASIN:1594868107 Dr. Neal Barnard's Program for Reversing Diabetes: The Scientifically Proven System for Reversing Diabetes without Drugs]].) So both low fat and low carb diets lower blood sugar and improve insulin resistance compared to the standard American diet.

Excess insulin is just one factor in a long list of things that affect Western diseases. Excess calories, excess IGF1, vitamin D insufficiency (See [[ASIN:B002B55DTA Vitamin D Prescription: The Healing Power of the Sun & How It Can Save Your Life]]), a sedentary lifestyle, a shortage of phytochemicals from fruit and vegetables, a shortage of omega-3, eating too much salt, excess alcohol and smoking all have huge effects on Western diseases. And according to Weston Price free range meat and dairy, organically grown food, minimally processed food, calcium and fat soluble nutrients and whole grains were important reasons for the health of the people he studied. Since just eating less carbs can't correct all these problems, even the beneficial Eco-Atkins is not a panacea for Western disease.

4) MISLEADING ABOUT HEART DISEASE : Dr. Esselstyn used a 10% fat, low glycemic index, high fiber diet to reverse heart disease. (See [[ASIN:1583333002 Prevent and Reverse Heart Disease: The Revolutionary, Scientifically Proven, Nutrition-Based Cure]].) We know it worked because of before and after coronary angiograms and cardiac PET scans. People given less than a year to live are alive and healthier 20 years later. Done right, the 10% fat, low glycemic index, high fiber diets reduce small dense LDL particles, inflammation, homocysteine, insulin resistance, blood sugar and increase nitric oxide which dilates arteries like nitroglycerin. There is no requirement to count calories or exercise to get these results.
Dr. Ornish also reversed heart disease using similar diet plus exercise and meditation. Since then Dr. Ornish has enrolled at least 3800 patients in demonstration projects (to demonstrate savings on surgery) which resulted in over 40 insurance companies including Medicare covering a program in diet and lifestyle for heart disease patients. According to Dr. Ornish, "In brief, we found that almost 80 percent of patients who were eligible for bypass surgery or angioplasty were able to safely avoid it for at least three years."

The book leads us to believe that lowering cholesterol may reduce heart disease but not increase longevity and that cholesterol levels don't matter in elderly people. But a meta-analysis by Afilalo et al. shows Statins reduce all-cause mortality 22% in elderly heart disease patients.

On page 454 GCBC says "Through their direct effect on insulin and blood sugar, refined carbohydrates, starches, and sugars are the dietary cause of coronary heart disease and diabetes." The initial studies by Dr. Esselstyn and Dr. Ornish that reversed heart disease on a low fat, high carb, high fiber diet are over 20 years old and something he knew about (because he debated Dr. Ornish in 2002) but chose not to mention!

5) MISLEADING ABOUT CANCER : The book leads us to believe that low cholesterol causes cancer. But calorie restriction lowers cholesterol and reduces the risk of cancer and heart disease at the same time. The latest meta-analysis of statin use, based on 26 randomized trials and 170,000 patients, shows they are not associated with higher cancer rates. Countries with low cholesterol have lower rates of prostate, breast and colon cancer than the U.S. In clinical trials, ultra low fat diets slow cancer growth. So why would low cholesterol levels in this country be associated with cancer? Because cancer and other chronic diseases cause lower cholesterol, not the other way around.

Complete protein is the main thing that raises IGF1 which increases the risk of cancer (whey seems to be the only exception). Cancer patients who eat low fat and low meat have much higher survival rates. GCBC tells us people can be healthy eating 100% meat, but fruit, vegetables, whole grains and beans contain phytonutrients that act like low dose chemotherapy. (See [[ASIN:0756628679 Foods to Fight Cancer: Essential foods to help prevent cancer]].) Even Sally Fallon, cofounder of the Weston Price Foundation, in her book Nourishing Traditions admits "... meatless diets often prove beneficial in the treatment of cancer ..." although she does not believe that meat increases the risk of getting cancer.

However in the Fung et al study mentioned earlier, people eating a version of reduced carb with 18% animal protein were 32% more likely to die of cancer than the Eco-Atkins group eating 12% animal protein. In other studies, red meat is associated with an increased risk gastric and colon cancer; saturated fat is associated with an increased risk of breast cancer and dairy is associated with an increased risk of prostate cancer. And in animal studies, cancer rates increase rapidly when complete protein is more than 10% to 12%.

According to the World Health Organization, modern adult humans only require about 0.38 g/lb per day of protein with a protein digestibility-corrected amino acid score (PDCAAS) value of 1.0 to be healthy and maintain nitrogen balance. And the average American eats about 50% more than this. (Pregnant women, children, adolescents, elderly people with congestive heart failure and people recovering from an infection or injury need extra protein.)

6) MISLEADING ABOUT PHYSICAL EXERCISE: Just walking 30 minutes a day reduces the risk of heart disease, cancer, diabetes, hypertension, and Alzheimer's. (See [[ASIN:0345496310 The Spectrum: A Scientifically Proven Program to Feel Better, Live Longer, Lose Weight, and Gain Health]].) Conductors in double-decker buses have about half the rate of heart disease as the drivers who sit all day long. And exercise benefits your health whether you lose weight or not.

CONCLUSION : THERE ARE SEVERAL WAYS TO BE HEALTHY

People are different but medical research can only tell us what is likely to be true for the average person in a carefully defined group using statistical analysis. Some people do best with low fat or Mediterranean and others with Eco-Atkins. Most people with heart disease do well on the diet of Dr. Ornish or Dr. Esselstyn. But there's no evidence that a diet high in grain fed meat is good for anybody in the long run.

1. Vegetarian Adventist men and women live an average of 87 and 89 years, respectively and have a typical cholesterol level in the 180s. They abstain from alcohol and tobacco, exercise regularly and eat nuts,  eggs and dairy products.
2. In the 50's and 60's Crete had the best longevity in the world. They ate 40% fat mostly from olive oil, but only 8% saturated fat. The total red meat, poultry and fish consumed per-person, per-week in Crete was only about 371 grams (13 ounces). Ancel Keys followed the Mediterranean diet and lived to be 100 years old.
3. Japan has the best life expectancy of any country. The average man lives 79.4 years and the average women 86.1 years. They eat more carbs (about 59% versus 49%) and less fat (about 28% versus 38%) than the U.S. They eat more seafood than they do meat.
4. Iceland has the best longevity in Europe. The average man lives 80.1 years and the average women 83.5 years. They eat less carbs and more fat than the U.S. They eat more seafood than they do meat and their meat is grass fed. (In France they also eat grass fed meat.)
5. If you have heart disease, a low-fat diet with low glycemic index, high fiber carbs can save your life. This diet is associated with higher levels of telomerase, an enzyme that maintains telomere length which is associated with health and longevity. Skim milk and egg whites are allowed. People without heart disease can eat more fat including wild salmon
6. An Eco-Atkins diet with regular meat, that includes 12% or less animal protein and 12% or less saturated animal fat has been shown to be healthier than the standard American Diet. Lower values give even better lipid profiles.
7. Eat like a hunter gatherer. But unless you have the right genes, eat grass fed meat and copy most of their protective behaviors you are not likely to get good results for heart disease and cancer (even if you lose weight and lower your blood sugar.)

Two bad choices

1) Follow the USDA pyramid version of low fat and eat lots of sugar, white flour, white rice and potatoes. It will increase your risk of the metabolic syndrome and diabetes.
2) Eat low carb with grain fed meat. It will increase your risk of heart disease and cancer.