The Low Fat Study
The direct quotes come from journalists and other commentators.
COMMENTARY: Some said the study was a failure because it didn't look at the type of fat in the diet (e.g. saturated v. unsaturated fat). But the study was designed to test whether low-fat diets work. And proved decisively they don't.
COMMENTARY: 'Keep saturated fat to 10 percent or less of total calories - 7 percent if you already have evidence of heart disease or diabetes - and keep trans fats as low as possible.'
Trans fat consumption should be ZERO. According to the National Academy of Sciences, there is 'no safe level' of consumption of trans fats.
The effect of natural saturated fats (butter) is to raise HDL. As to the virtues of HDL, the National Cholesterol Education Program is clear: 'the higher the better.' I am aware of no clinical evidence showing lower mortality from any cause when saturated fats are limited to 10% of calories compared with a diverse diet including all traditional fats. Mainstream fats researchers have lamented the very lack of such evidence.
In December 2005, the journal Lipids reported in a special issue devoted to stearic acid (a saturated fat in chocolate and beef) that stearic acid lowers LDL. When researchers discovered this about stearic acid in the 1950s, did they tell us that dark chocolate and steak are good for you? No, they proposed to reclassify stearic acid and not group it with other saturated fats!
The advice to limit saturated fats to 10% of fat calories is not well considered. Suppose you ate only olive oil (the 'good' fat). You would consume 14% of your fat calories from saturated fats because olive oil is 14% saturated.
Furthermore, God did not create fats in order to raise or lower blood cholesterol. All fats (monounsaturated, polyunsaturated, and saturated) have vital roles. Saturated fats in particular boost immunity, aid digestion, aid calcium absorption, and extend the life of omega-3 fats.
These functions are well understood by chemists of fats and nutrition, but if anecdotal evidence is more your speed, here is one story.
On a strict diet of olive oil only and zero saturated fats (only non-fat yogurt, no animal fats, no cocoa butter), I suffered from three symptoms typical of saturated fat deficiency: immune problems, digestive problems, and omega-3 depletion. All of my symptoms disappeared when I began to eat butter, cream, coconut oil, and other saturated fats.
What about the dread LDL? In half of all heart disease cases, LDL is 'normal' or 'desirable.' In other words, 'high' LDL predicts heart disease with the accuracy of a coin toss. In older men and women, high LDL means you live longer. (These studies are in my book, Real Food. For more facts like these, see The Cholesterol Skeptics.)
Cholesterol is a poor predictor of death from heart disease. We have been eating natural saturated fats for 3 million years. They are perfectly healthy.
COMMENTARY: 'You don't want to take meat out of the diet and add Wonder Bread or Snackwells. What you want to do is add things like soy burgers in place of hamburgers and use canola and soybean oil on your salads.'
Odd, isn't it, how consumption of meat and saturated fat declined in the US in the latter half of the 20th century, while heart disease rose? Here's another one they call the 'Spanish Paradox.' In 1975, the Spanish got a lot richer. They began to eat more meat and saturated fats and less cereal and pasta. From 1975 to 1990, death rates from heart disease fell by 35%.
Natural beef, sausage, venison, and other red meat do not cause heart disease or cancer.
Industrial soy, meanwhile, is a poor replacement for quality animal protein. It causes other problems, including thyroid dysfunction, hormone disruption (from excess estrogen), and interference with mineral absorption.
Soy bean oil and other polyunsaturated vegetable oils are far too rich in omega-6 fats, which promote obesity, diabetes, heart disease, and cancer. With too many omega-6 fats, the body is unable to make a range of crucial hormone-like agents responsible for multiple functions from immunity to skin health. The hormone-like agents made from omega-3 fats (from fish) have the opposite effects. Most Americans eat 10 to 20 more omega-6 oils than omega-3 oils. The healthy ratio is one to one.
Eat fewer 'yellow' oils (corn, soy bean, safflower) and more 'pink' oils (from fish such as sardines and wild salmon).
COMMENTARY: The WHI study 'allowed researchers to question some popular notions about diet and obesity. There is a common belief that Americans get fat because they eat too many carbohydrates. The idea is that a high-carbohydrate, low-fat diet leads to weight gain, higher insulin and blood glucose levels, and more diabetes, even if the calories are the same as in a higher-fat diet. That did not happen here.'
That 'did not happen' here because neither diet restricted carbohydrates! The WHI study did not attempt to confirm that it's easer to lose weight eating protein than flour, the gist of several sensible and balanced diets. These diets are not recent, by the way. In the 1950s, the nutritionist Adele Davis advised eating protein and limiting sugar for 'reducing.' That's how hunter-gatherers stay thin.
On what grounds do the commentators suggest that the WHI study disproved the already-proven sugar and insulin mechanism of weight gain? Because the low-fat group didn't lose weight! Note the logical fallacy. What they found was that a low-fat diet doesn't help you lose weight. They did not attempt to test whether a low-sugar diet would help you lose weight. But we know it does. Carbohydrates, especially simple carbohydrates like sugar, have a large effect on insulin and thus fat storage; the effect of fat on insulin is zero.
Neither group lost weight because both groups ate generous amounts of carbohydrates - by design. (One was deprived of fat.) The low-fat group ate an extra one-half serving of grains daily. This is not a significant increase in carbs to compare the two groups on weight loss.
What both groups did eat was a low protein diet, with 17% of calories from protein, and 47-53% of calories from carbohydrates - not in any way a low-carbohydrate diet, much less low in refined carbs. (Whole grains slow the insulin response.) Many nutritionists recommend 25-35% of calories from protein for weight control.
A 'moderate' and balanced diet is 40% carbohydrate and 30% each from fat and protein. Consistent with our cheap grain policy, the US government recommends a lot of carbs: 55% carbohydrate, 30% fat, and 15% of calories from protein. Note that the none of the women in the low-fat study (who, remember, did not lose weight) ate as many carbs as the US government recommends. I wouldn't try.
COMMENTARY: 'Even 'bad' carbs aren't so bad.'
The study offered no evidence for or against whole grains versus refined carbohydrates such as white flour and corn syrup. Both groups ate mostly refined carbohydrates and a paltry one serving of whole grains daily. For people who are sensitive to carbohydrates, any carbohydrate (even whole grains) may lead to weight gain. In people with gluten intolerance and colitis, almost no grains are healthy. Rice and millet may be tolerable.
What about fruit & vegetables?
The study failed to show anything useful on fruit and vegetables, because they could only get the low-fat group to eat an extra one serving of fruit and vegetables daily! Recall that one cup of lettuce (a bare handful) or one-half cup of cooked spinach is a serving. Again, a paltry increase. Evidence supporting eating large, daily, and diverse quantities of fresh produce is abundant in any case.
Statin Drugs Don't Work in Women
An interesting (but ignored) finding of the study was this: statins had no effect on death rates. This confirms other findings, showing that for women and especially elderly women, statins are of no benefit.
Low-Fat Diets Don't Work
It's worth repeating the main findings: the 49,000-woman, 8-year 'Rolls Royce' of studies demonstrates definitively that total fat intake does not prevent heart disease, cancer, or stroke, and that a low-fat diet does not aid weight loss.
Typical, healthy, and traditional fat intake is 35-45% of calories. The women who ate anything they wanted got about 37% of calories from fat - just right! Thus you don't need to count grams of fat (or anything else).
Fats do matter, however. Fats that contribute to heart disease, cancer, and stroke are not traditional foods but industrial ones: trans fats and polyunsaturated vegetable oils. Avoid them like the proverbial Black Death and you'll live long and happy. (They don't taste good, either.)
For Geeks & Professionals: Look Up the JAMA Paper
'Low-Fat Dietary Pattern and Risk of Cardiovascular Disease.' The Women's Health Initiative Randomized Controlled Dietary Modification Trial, published in JAMA, February 2006. In that issue, researchers also reported findings from the same study on breast cancer.
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