Sunday, April 06, 2008

So what's the big (low-fat) deal?

By James J. Gormley
Okay, so $415 million later the Women’s Health Initiative (WHI) Dietary Modification Trial not long back proved what we in the health-food camp have already known for ages — that fat balance and fat quality are key in promoting health and reducing the risk of cancer and heart disease.

The biggest-ever study to look at whether a low-fat diet can lower the risk of cancer or heart disease — one involving nearly 49,000 women aged 50 to 79 who were followed for eight years — found that, overall, a low-fat diet had no protective effect against these diseases.

As Harvard’s Dr. Walter Willett pointed out to the Washington Post at the time, “This should be the nail in the coffin for low-fat diets.”

Maybe, but low-fat and non-fat were, after all, bright, shining beacons of hope from a medical/public-health establishment that has, over the years, produced a series of health intifadas against such erstwhile “evils” as butter (not bad for us in moderation), salt (no persuasive evidence that it’s bad for the heart) and later, of course: fat.

Although public health groups are now saying that they had already well abandoned the “fat is bad” mantra a long time ago, the truth is that, as recently as 2000, the National Cancer Institute (NCI) was issuing cheerleading recommendations for low-fat and high-fiber diets in its Action Guide for Healthy Eating:

“Much research in the last few years has shown that […] eating a healthy diet, low in fat, high in fiber […] may help to lower cancer risk.” The NCI’s related “Action List for Fat” calls for consumers to use reduced-fat or non-fat salad dressings, low fat and fat-free foods and, you guessed it, margarine.

Today, it is known that low-fat salad dressings ironically lead to more weight gain than do their full-fat counterparts since tons of the fat-deprived dressings are heaped on salads since these poor cousins don’t make people feel full.

In terms of high-fiber, a 2005 review of 13 studies that appeared in the Journal of the American Medical Association found that high-fiber diets did not reduce the risk of colon cancer. We also know today that traditional tub margarine is loaded in heart-unfriendly partially hydrogenated (trans) fats.

One danger of these findings about the failings of low-fat diets is that people may feel the converse is true — that we can eat fat (of any kind) in unlimited quantities. False — saturated and trans fats will always be unhealthful, yes, however supplementation with high-potency, purified omega-3 fats is very healthful (and always will be).

Another danger is that people might believe that all dietary advice is unreliable and bad, and that everything should be discounted, which would be very wrong.

Although it is too bad the study did not employ generous levels of essential fats from the Mediterranean Diet, which is rich in omega-9 fat (olive oil) and omega-3 fats (mainly from fish) rather than cutting down all fat, alas it did not.

As I wrote, in DHA—A Good Fat, in 1999, “A balance of fats is what’s critical. […] a balance which existed, by and large, prior to the cholesterol crazes and low-fat/fat-free mania” that began a few decades ago.

Take away? Let’s keep eating healthfully, exercising, and thoughtfully supplementing, while feeling just a wee bit smug that we were right all along.

[Adapted from an editorial that originally appeared in Remedies magazine]
The Gormley Files - Blogged