Is it just me, or does every new study and food book offer conflicting advice? I'm not happy to hear that we should limit fat and eat lots of whole grains and vegetables; but nor am I thrilled to hear saturated animal fats are back on the menu and carbs are the new bad guys. Can't I love both? Can't we all get along???
This week I took on Nina Teicholtz's The Big Fat Surprise.
Like Gary Taubes' WHY WE GET FAT, Teicholtz takes on some 50 years of dietary advice from the government, academy, food-, and health-powers-that-be. You know the drill: reduce saturated fat in the diet. The higher your heart attack risk, the more drastically you should reduce it. That means cutting out red meat, eggs, milk, cheese--and voila! You'll lower your LDL and live long enough to die of cancer instead.
Teicholtz traces the ascendancy of this advice and the effects of personal biases, statistical hand-waving, and academic infighting on the conclusions drawn or suppressed. She looks in depth at the original studies done and cited, rather than taking the abstract's or another person's word for it, with surprising results. As it happens, rates of heart disease have not declined, despite a 17% increase in American consumption of fruits and vegetables, a 29% increase in grains, and a reduction of fats to 33% of calories. In place of animal fats we now consume 8% of calories by way of vegetables oils (mainly soy and canola), and, in the meantime, obesity, diabetes, and cancer rates have boomed. What went wrong?
A few things:
- We found "lowering cholesterol" was not the cure-all we hoped for. Lowfat diets (and statin drugs) can lower LDL, but it turns out general LDL levels do not correlate closely with heart disease. Having high, small-particle LDL levels does seem to correlate, but the best way to sway the balance to big, floaty LDL particles is to eat animal fats.
- The "Mediterranean Diet" was somewhat an arbitrary invention, but a diet favoring olive oil does seem to improve health factors better than a lowfat diet, although not as well as a diet rich in animal fats.
- At first animal fats were replaced in processed/fast foods with trans fats, but when these started to be frowned upon, everyone switched back to liquid vegetable oils, which oxidize and put out toxic aldehydes when they are heated.
- Calcium and vitamins A, D, K, and E are fat-soluble, meaning they cannot be fully absorbed if not accompanied by fat. That goes for the calcium in nonfat milk and all the spiffy vegetables sprinkled in fat-free dressing.
- Women and children were recommended to follow lowfat diets by extension, but it turns out women with low cholesterol had higher mortality rates that women with high cholesterol, and women on lowfat diets see a greater drop in their good HDL levels than men. Kids need saturated fat for ideal growth.
- When not replacing trans fats with liquid oils, food processors have to rely on fat replacers, which are additional carbohydrate substances.
- Liquid vegetable oils are pro-inflammatory and tied to increased rates of cancer.
...There's more to say, but I'll stop here. Suffice to say, I found the arguments convincing, if depressing, given my deep love for bread and pasta. My kids have been drinking whole milk for years now, and I am determined to wean us at least two days a week from breakfast cereals, but I just don't know how the world can support everyone on a diet high in animal fats. Not to mention, meat is expensive, especially since we do grass-fed. I suppose I'll have to settle for increasing our ratio of animal fats and reducing our refined carbs and liquid vegetable oil.
At least I can fry in butter and bacon fat without a twinge of guilt now, but I guess this means my homemade pot stickers fried in vegetable oil literally are to die for!