Tuesday, December 04, 2007

disgusting details about fat, scurvy, and fiber

I’m about 60% through the Taubes book now and it’s steadily getting more intriguing.

I like the bit in Chapter 18, Fattening Diets, where the author describes the diets of sumo wrestlers: about 5500 calories a day, very very low in fat (16% of total calories) and high in carbs (57%). And that’s for the top-ranked sumo wrestlers. The lower-tier competitors, who weigh about the same but have less muscle mass than their brethren, eat about 5100 calories a day, but up to 80% is carbs (this means proportionately less protein, hence the reduced muscle) and as little as 9% fat. (p307)

That right there should end the debate about whether it is fat or carbs that make you fat. And please note that the sumo are not fat because they eat so many calories; no, they crave enormous amounts of food because all the rice kicks their insulin levels sky-high and they are hungry all the time. Trust me; I lived with a guy who was sumo-sized for several years and this was exactly how he ate. He liked his meat ok, and he could take or leave butter, but he'd polish off a loaf of Wonder Bread literally overnight.

Chapter 19, Reducing Diets, talks about a guy named Stefansson who lived with the Inuit (Eskimo) for a decade before WWI, during which he ate their native diet of fatty meat and little else, and suffered no ill effects. If anything, he was healthier than he had been on his previous “balanced” diet, as were the Inuit and all the foreigners who came to live with them and adopted the diet.

Laboratory attempts to replicate this diet on volunteers, in the 40’s and 50’s, yielded much the same results. The volunteers lost weight, eating as many or more calories than they had before the experiment, except with the carbs greatly reduced, and while they were losing body fat and inches, they gained muscle, felt more energetic, suffered no hunger pains, and in the case of some female college students, saw their skin clear up.

All of that I knew, and could attest to personally. Here’s the kicker:

None of the volunteers on this diet of meat and fat suffered from malnutrition. They didn’t get beriberi (thiamin deficiency), or pellagra (niacin deficiency) or even scurvy. This surprised me. I’ve heard repeatedly that humans and guinea pigs are the only two mammals who can’t synthesize vitamin C in their bodies, and I always assumed that vitamin C was the only thing I might need to supplement myself with. There is little or no vitamin C in meat, milk, eggs and cheese.

So why did I never seem to be bothered by scorbutic symptoms? I figured it was because I ate enough green stuff, although if I’m being strictly honest with myself, I don’t eat much. More to the point, why didn’t the Inuit and their guests get scurvy after years on such a diet? I'd never seen this question addressed before; it was one of the questions those post-WWII researchers were trying to answer.

Turns out that “high blood sugar and/or high levels of insulin work to increase the body’s requirements for vitamin C. The vitamin-C molecule is similar in configuration to glucose and other sugars in the body. It is shuttled from the bloodstream into the cells by the same insulin-dependent transport system used by glucose. Glucose and vitamin C compete in this cellular-uptake process, like strangers trying to flag down the same taxicab simultaneously. Because glucose is greatly favored in the contest, the uptake of vitamin C by cells is globally inhibited when blood-sugar levels are elevated.” (p325)

In other words, the starches in our diets flush the C out of our systems, while inhibiting the use our bodies can make of the C we get. That would explain those studies that show how mega-doses of C just get flushed out in the urine. The high-carb diets prevent our bodies from absorbing it. So the greater proportion of carbs in your diet—including root vegetables, legumes, and particularly fruits—the more C you need to injest just to break even. And all that pureed fruit juice will do you no good: your body will just soak up the sugars and flush the vitamins right out of there.

I had no idea. But maybe it helps explain why I hardly ever get sick.

Also, that old saw about excessive protein damaging your kidneys? That came from a guy named Newburgh who force-fed soybeans, eggs and beef to rabbits. Rabbits are herbivores—one could hardly be surprised if a diet of this sort gave them health problems.

The human subjects who participated in various high-fat, high-protein diet studies, which Taubes discusses in the last third of the book, suffered no kidney problems, and no problems with bowel disruptions. Lest I venture into the realm of Too-Much-Information, I can verify that my guts work smoother, produce less waste and less odor, when I eat fewer carbs and starches. A friend of mine, who was once diagnosed with Irritable Bowel Syndrome, reported the same improvement with his change in diet--which makes me cringe for those poor bastards with IBS who are told to increase their fiber.

Frankly, I never saw the point of eating a high-fiber diet. That argument is based on two things: one, that the fiber will fill you up and you will feel less hungry; two, that fiber is ‘nature’s broom’ and will sweep out the nasty bad meat waste.

First of all, eating things that are not food will not stop you from being hungry. The Donner party chewed on shoes, ate paper and boiled rugs for broth, but it didn’t stop them from starving. If you dilute the food of rats with water, they will keep feeding until they bloat, but they will not stop until they have consumed their usual number of calories. It’s a nutrient-balance thing; volume has little to do with it.

Second—what meat waste? The protein is going to my muscles; the fat is soothing my liver, processing vitamins, making my skin and hair silky. So I have to wince when I hear dieticians, particularly the vegetarian variety, pushing fiber on people. All you’re doing is making your bowels and small intestine work harder for fewer nutrients.

Not efficient, to my way of thinking.


Lisa said...

First, I really enjoy your food posts. Just wanted to get that out of the way.

Second, I have to find this book you're talking about because it sounds interesting. I did a modified version of the low carb diet a few years ago and it had a huge positive impact on my general health and well-being, so none of what you say in this post surprises me.

I am hypoglycemic, so I pretty much switched to a low-glycemic/diabetic diet. I didn't eat steak for breakfast or anything nuts like that, but I did have an egg every day in the morning and increased the oily fish in my diet. When I eat red meat I usually just go for filet, but also eat a lot of other lean meats like turkey and pork. I try to keep all of my servings to the size of my palm. I try to keep my meals balanced between carbs and protein, and tipped a little toward more protein when I can.

I also made my own yogurt for a while. These two dietary changes together stopped my sugar crashes, cleared up a brain fog I didn't even know I had and evened out my mood. This might be TMI, but it helped me in intestinally as well. I have a family history of Crohn's and colitis and was ready to get some medical help if this hadn't made such a difference.

Fiber does seem to help reduce cholesterol, but those fiber supplements are nasty and the side effects of the can make you feel just as bad as the reason for taking them. Nutritionists stress that getting what our bodies need from food instead of supplements is best, so I occasionally add some ground flax seed to my oatmeal. However, I have to make sure I couple that oatmeal with some protein or an hour later I'm crashing.

Corbie said...

Neat post. Pretty much corresponds to my experience with low-carb, too.

Holly said...

Lisa, I hope you will find and enjoy Good Calories, Bad Calories. I certainly found it eye-opening. It also devotes a great deal of space to the cholesterol myth--bottom line? There's no evidence, not even a corellation, between high blood cholesterol and heart disease. Zip. Zilch.

There's a nice summation of the subject here: http://creativerefuge.com/pages/eatnaturally5.htm

Thom said...

Ugh... there's SO MUCH misinformation flying around about this topic.

It's worth checking out this blog post here at the Dietary Supplement Information Bureau. Refreshingly unbiased, but plenty of scientific results to validate their points..

Holly said...

Thanks for the link, Thom. It never hurts to have common sense reiterated.