saturated fatTag Archives

Dr. Eades on lard

Who would think that we’d actually see a medical doctor post an entry on his blog called “Add lard to your larder”? Dr. Michael Eades, the author of Protein Power, did just that. Among interesting points that he made, he said that the Mediterraneans are actually eating lard more than olive oil. The olive oil they produce in the region is for export. That certainly changes the face of what many believe is one of the healthiest diets!

In another of his posts about “The best low-carb book in print,” he quotes study summaries from the book. One study was particularly interesting. They looked at an ADA low-fat/high-carb diet against a low-carb/high-fat diet. I like studies like this because it pits one intervention diet against another, thus eliminating the conscientiousness factor when comparing the diets. Even though the high-fat dieters were eating considerably more saturated fat, the blood levels of saturated fat decreased from their pre-diet numbers, both in terms of percentage of fat in the blood and in terms of the absolute serum content. By the latter measure, saturated fat in the blood dropped 30% in the high-fat group, even though they were eating more saturated fat. Triglycerides fell by 51% in this group. The latter figure did not surprise me much because I already knew that triglycerides increase with carb intake. It would have been nice to know how they did weight-wise, but Dr. Eades did not quote those results. I guess I’ll have to get the book to find out.

Dietary fats and atherosclerosis

The following is a review of the study, Dietary fats, carbohydrate, and progression of coronary atherosclerosis in postmenopausal women, published in The American Journal of Clinical Nutrition. It’s one of those studies that can make your blood boil because it would indicate that we’ve been given some really bad information over the years about what to eat to prevent heart disease.  This summary of it got me interested in checking out the details:

“A 2004 study from Brigham and Women’s Hospital and Harvard School of Public Health showed that in postmenopausal women, the more PUFA [polyunsaturated fatty acids such as from vegetable oil] they ate, and to a much lesser extent the more carbohydrate they ate, the worse their atherosclerosis became over time. The more saturated fat they ate, the less their atherosclerosis progressed; in the highest intake of saturated fat, the atherosclerosis reversed over time.”

They chose for their study postmenopausal women who’d already had a heart attack and who had measurable atherosclerosis in their arteries. This study is important because it shows that the advice we have been given by the USDA and major medical organizations for preventing cardiovascular disease is the opposite of what actually works. The fact that some of these women were able to reverse the progression of their atherosclerosis is significant as well. We don’t often hear of that happening. The participants eating the most saturated fat were also eating more total fat. In general, the ones eating the most saturated fat had the best lipid profiles. Those eating the most saturated fat were eating more protein and less carbohydrate than other groups. Those eating the most carbohydrate had the greatest decline in coronary artery size. To a lesser extent, those eating the least total fat had the greater decline in coronary artery size. Among types of fat, polyunsaturated fat was associated with the greater progression of atherosclerosis. Particularly noteworthy were actual improvements seen when monounsaturated fat displaced saturated fat and when protein displaced polyunsaturated fat. Stearic acid, most often found in animal fats, was associated with lesser progression (better outcome) than other saturated fats. Oddly, smoking was inversely associated with progression of atherosclerosis. I would say that the summary I read the other day held up under closer review.

This was an observational study. There were no interventions done. In the discussion section of the study, they presented a chart of intervention studies. Many of them studied an intervention to increase the ratio of polyunsaturated fat to saturated fat. Most of these showed improved outcomes for the intervention group. I have to wonder, though, if intervention groups were eating better in other ways as well. Perhaps they were eating less processed foods, too, which could have a tremendous impact on the results of the study. After all, in this study that I just read, carbohydrate intake was highly correlated to progression of atherosclerosis. Considering that grain desserts and pizza are the largest identified sources of saturated fat in the American diet according to the USDA, this could well be the case. Intervention studies in the chart where they increased consumption of certain whole foods generally showed a strong trend in improved outcomes. Only an examination of the other individual studies could determine if change in consumption of processed foods was properly accounted for and analyzed for confounding. Did these studies have only two groups, a single intervention group and a control group? It would be more interesting to see a single study with multiple intervention types and compare those outcomes since an intervention group is more likely to be conscientious, and conscientiousness is likely a confounding factor when comparisons are made to controls. An observational study such as the one I just read would be less impacted by conscientiousness. As for a multiple intervention study, I wonder if scientists would be brave enough to create an intervention group where saturated fats from grain desserts and pizza were replaced by higher quality sources of saturated fat that did not come with a boatload of refined carbohydrates, thus retaining the level of consumption of saturated fat but eliminating the junk. Comparing that intervention group to an intervention group increasing the ratio of polyunsaturated fat might yield different results entirely. It remains to be seen. Interestingly, studies where the ratio of monounsaturated fats was increased were not listed. Have they not been done?

Looking at the USDA Dietary Guidelines

Today’s reading included a blog post by Denise Minger looking at USDA recommendations. The USDA recommends reducing saturated fat in the diet as well as reducing overall fat content. In their library of supporting documents, only one of the 12 studies cited actually supports these recommendations. The one study that does, a meta-analysis of studies, is later contradicted by a larger meta-analysis that shows no improvements. The first study is apparently confounded by publication bias. To further confound such studies, the USDA presented a pie chart showing where saturated fat in the American diet comes from. Grain-based desserts and pizza provide the largest portions of saturated fat in the American diet. But I just learned from the “Forks over Knives” post that China Study II positively correlates wheat with heart disease death and deaths from all medical causes. In fact, wheat correlates with heart disease better than any other food. Those grain-based desserts and pizza that we’re getting our saturated fat from have a lot of wheat in them. Meanwhile, animal protein and animal fat were negatively correlated in that study, meaning that death rates were lower. That’s an interesting finding from a scientist who promotes a vegan diet. So anything showing that saturated fat is harmful is likely confounded by the junkie carbohydrate and wheat intake that often accompanies the saturated fat. Furthermore, studies supporting increased intake of polyunsaturated vegetable oils are confounded by the overall healthier habits of those consuming those oils. When the data are corrected for these healthy habits, the benefit of the vegetable oils disappears.

By the way, the cited USDA studies and also Dr. Caldwell Esselstyn’s results cited in “Forks over Knives” blog post would support my modifications to the NutriSystem diet for attempting to keep my cholesterol levels healthy. This further increases my optimism that I have made the right modifications. We’ll see when I get the results back from this coming Thursday’s blood draw.

As an interesting aside, the USDA was unable to be conclusive as to whether fruits and vegetables are actually good for you. They say further study is needed. Very interesting indeed! Results from China Study II would support the inclusion of green vegetables, at least, since they are negatively correlated to deaths from all medical causes. Fruit is positively correlated with deaths from heart disease, stroke, and diabetes in that same study, though. Have I not said before that fruit poses problems due to the sugar content? That’s why I decided to eliminate fruit from my modified diet. There are better sources for the micronutrients fruits provide among the vegetables, and I do make sure to include those.

U.S. Department of Agriculture, U.S. Department of Health and Human Services. Dietary Guidelines for Americans 2010.
Denise Minger. The New USDA Dietary Guidelines: Total Hogwash, and Here’s Why, Raw Food SOS.
Denise Minger. “Forks Over Knives”: Is the Science Legit? (A Review and Critique), Raw Food SOS.

Critique of studies on which our “healthy diet” advice is based

I just read Dr. Mercola’s critique of the principal studies on which our “healthy diet” advice is based, The Cholesterol Myths that May be Harming Your Health.  It would seem that there’s a lot of misleading information being promulgated.

To start with, Dr. Ancel Keys cherry-picked his cases for the Seven Countries Study back in 1953 when he told us that higher fat intake correlated to higher rates of coronary heart disease.  Had he used data from all 22 countries that had data available, no correlation between dietary fats and coronary heart disease would have been found.

Analysis of the Framingham Study showed that lower blood cholesterol levels were associated with a lower cardiac risk.  What they did not tell us was that the same study determined that the more cholesterol and saturated fat people ate, the lower their blood cholesterol levels.  And yet we were told to lower our cholesterol and saturated fat intakes.

And finally, while the “MrFit” Study did show a marginal decrease in coronary heart disease for those who ate a low-saturated fat and low-cholesterol diet, there was an increased all-cause mortality rate for those who followed such a diet with an increase in deaths from cancer, brain hemorrhage, suicide, and violent death.

Does the American Heart Association know about these studies?

I continue to read Natural Health & Weight Loss by Barry Groves.  I am currently reading about fats.

A study was done in 1965 by Rose GA et al to assess survival rates in patients eating different fats and oils.  In this study, patients who had already had a heart attack were assigned to one of three groups.  These were given polyunsaturated corn oil, mono-unsaturated olive oil or saturated animal fats respectively.  Blood cholesterol levels were lowered by an average of 30% in the polyunsaturated group, while there was no change in the other two groups.  At first sight, therefore, it seemed that men in the polyunsaturated group had the best chance of survival.  However, at the end of the trial only 52% of the polyunsaturated group were still alive and free of a second heart attack.  Those in the mono-unsaturated group fared little better: 57% survived and had no further attack.  But the saturated animal fats group fared the best with 75% surviving and without a further attack.

There was also a Finnish trial published in 1985 by Miettinen TA et al in which middle aged men were given interventions such as instruction on diet, smoking, and exercise and were also treated for high blood pressure and cholesterol when present.  The control group was given no such interventions.  At the 15-year follow-up, there were 67 total deaths and 34 heart disease deaths in the intervention group.  In the control group, there were 46 total deaths and 14 heart disease deaths.

Would it be fair to say that we are being given bad advice where it relates to heart health?

Barry Groves. Natural Health & Weight Loss, 2007.
Rose GA, Thomson WB, Williams RT. Corn oil in treatment of ischaemic heart disease. Br Med J. 1965 Jun 12;1(5449):1531-3.
Miettinen TA et al. Multifactorial Primary Prevention of Cardiovascular Diseases in Middle-aged Men, JAMA. 1985;254(15):2097-2102.