The apostle Paul wrote to the Colossians, "Why … do you subject yourselves to ordinances: Do not handle, nor taste, nor touch, (Regarding things which are all to perish when consumed) …?" He went on to say that "such things indeed have a reputation of wisdom", but were otherwise without value. He was writing about asceticism, which infected the early church within a matter of months after the resurrection and ascension of Jesus, and to some extent the infection remains to this day.
A similar infection is found in the secular world, with prohibitions about many, many things. In particular, food prohibitions are rampant. Food, as a necessity, comes right behind air and water. For most of us, the time spent obtaining food and groceries, cooking, eating, and cleaning up must add up to at least a couple hours a day. And, wouldn't you know it, everybody seems to have advice about food.
I have no idea how many "weight loss" diets there are, but health.com ranks 38 of them on this page! Then we also find multitudes of shrieking voices from all sides, "Meat is poison!", "Salt kills!", "Eggs are heart-attack pills!", and on and on and on. There must be at least 100 holier-than-thou stances on food that is healthy (or not), moral (or not!), or meets one or another standard of "sustainability".
Let's face it. Humans are omnivores. We can eat anything that was once alive, and a few things that never lived (like salt). Hmm…strike out "that was once alive": raw oysters live a little while in the stomach, as do swallowed goldfish. And come to think of it, when you eat a piece of fruit or other raw vegetable, it is still alive. We can eat anything living or recently dead.
But just to drive the point home: one of our closest evolutionary cousins, the Gorilla, is a strict herbivore. Gorillas are vegans. They eat leaves, and they have very long bowels for their size. They also ruminate, even though they don't have a rumen like a cow or deer or sheep does. I have watched a large male gorilla spend an hour or so eating leaves and stems. Then he brought up a mouthful of "stomach gunk", spat it in his hand and looked at it (I also looked; it looked like greenish feces), then put it back in his mouth and chewed it for a while. After swallowing, he brought up another mouthful and the performance continued, presumably all afternoon. I went on to observe other primates after watching a half hour of rumination. A gorilla has a huge pot belly. They are adapted to eating food with few usable calories, even after rumination, so they have to eat lots and lots of it. By contrast, a wolf or lion has a much shorter bowel. They eat only meat. Meat has many more calories per ounce than a diet of leaves, even leaves of delicious Romaine or Kale (eaten raw). A short gut is sufficient to get most of the caloric value from a meat diet.
Humans, bears, and other omnivores have bowels of middling length. The human small intestine is around 20 feet (6m) long, and the large intestine is about 5 feet (1.5m) long. Though a male gorilla weighs about twice as much as a man, its "small" intestine is 60-70 feet (18-20m) long and its large intestine is also longer than ours, plus larger in diameter. That's what it takes to eat leaves, even the tender, choice leaves the Gorilla selects.
OK, on to the book of the week: The Bad Food Bible: How and Why to Eat Sinfully, by Aaron Carroll, MD, a pediatrician who got into nutrition and education because so many parents asked him how to feed their children. He didn't just look up "received wisdom", but dug into the subject. The more he looked, the more surprised he found himself.
Let's cut to the chase, then backtrack a little. This is the bottom line:
Almost every "Don't eat that!" prohibition is wrong.Y'got that? Sure, we all know not to eat rat poison, but you know what I really mean, right? At different times in the past, and up until today, we got all kinds of advice:
- Butter and the fat in red meat cause heart attacks
- Eating eggs and shrimp raise your cholesterol level
- Coffee is bad in a whole lot of ways
- Gluten free is the way to go
- Diet soda will give you diabetes
- Don't eat food full of chemicals
- Organic, ORGANIC, ORGANIC!!!
Oh, you meant we should avoid "artificial" chemicals? Glucose has the chemical formula (CH2O)6. So do several other sugars; they differ from one another because of the way the "H" and "OH" groups hang off the 6-carbon ring that is the backbone of most simple sugars. It is possible (not too hard, really) to make glucose in a laboratory, with test tubes and stuff. Once you crystallize it a time or two to purify it, there is no difference from the stuff made by grapes, or apples, or many other sweet fruits. In your body, many other kinds of sugars and starches (polymerized glucose, mainly) are turned into glucose, and whatever you don't need immediately is converted first to glycogen and stored in the liver, and any excess beyond a certain amount of that, is converted to fat and stored all over the place. Also, excess protein can be turned into glucose or glycogen or fat, depending on the balance of nutrients in the body at the time. And, if you are really low on recent calories, such as after a fast, your digestive apparatus can convert any fat you eat into glucose (and some waste materials). But you have to eat protein to build protein; carbohydrates (including sugar) and fats do not contain nitrogen, which is a part of every link in every protein chain. It is all chemicals, from end to end.
So, is there such a thing as "bad food"? Only in the sense of spoilage! Yeah, if that hunk of leftover roast in the back of the refrigerator is now green and fuzzy, it is probably "bad". If you aren't squeamish, though, you could probably re-fry it and eat it with no ill effects. But what is the "bad food" in The Bad Food Bible? Think things you've been told are "bad for you." Dr. Carroll picked out 11 famously hated foods that turn out to be not all that bad after all.
Along the way, the author discusses at some length just what "medical evidence" truly is. When someone says or writes, "Studies show…", we need to ask, "What kind of study?" He discusses several kinds of things that are called "studies" when people are being sloppy. The story by your Aunt Millicent, about the liniment that a local cobbler makes up, and how "wonderful" it is for her "palpitations" is an anecdote. That's a 50-cent word for "story". If you gather 1,000 stories, is that research? No it is still stories. But someone with an agenda just might call it a "study". To what were the stories compared? How many people tried the cobbler's liniment and never finished the first jar because it just made them feel oily and smell bad?…and it didn't help anyway. Without knowing how often it didn't work, you don't know anything useful about that liniment. At the other end of the scale is the mighty RDBCT, the Randomized, Double-Blinded, Controlled Trial, frequently shortened to RCT. This is called the Gold Standard, for two reasons. Firstly, a properly conducted RCT is truly valuable; it is the only kind of "study" that can determine cause and effect. Every other kind of study can at best hint at, or maybe strongly indicate, an association. For example, it is known that a higher proportion of alcoholics get lung cancer. Does that mean that alcohol can cause lung cancer? No. It was hard enough getting proof that smoking causes lung cancer! Rather, there is a secondary association that provides the link: A high proportion of alcoholics are also smokers. So, the chain of evidence is
- Smoking → Cancer
- Factor X → both Smoking and Alcohol Abuse
Whatever "Factor X" is, it must be one of several things that, taken together, make a person more likely to either smoke, abuse alcohol, or both.
The other reason that RCT's are called a Gold Standard is that they are very expensive. Food is one of the biggest industries out there. Food is, quite literally, a trillion-dollar enterprise. So there must be lots of research that has been done on food, using high-quality RCT's, right? No, they are rather rare. Dr. Carroll has to do a lot of digging to find an RCT here or there, and then he must assess the quality. Many try, but few do it well. So most "studies" just don't have the oomph to tell us anything useful.
Where there is gold, there are gold seekers. Among the multitude of paid-for "studies" about food, if you can follow the money you can reason out the conclusion that the researchers were asked to find. That's right. Much "research" was done to "prove" one point or another. Here is the biggest smoking gun: We've heard for 50 (maybe 100?) years that eating too much fat makes us fat, and that saturated fat was the worst. But the early "solution" to saturated fats was margarine, which turned out to be about 40% trans fats, which are much worse for us than saturated fats! Where are the studies that prove that eating fat causes us to get fat? Those that exist are actually poor in quality and there are hardly any RCT's, …and those show little or no association! But a lot of lower-quality "studies" were published, and guess who paid for them? The sugar industry. Now that a few folks with the financial backing to do so have begun conducting RCT's about it, the real culprit is sugar.
Humans lived for tens of thousands of years on high-protein, high-fat, low-sugar diets. Our bodies are used to coping with that. I remember reading an archaeological report about a Roman colony that was abandoned 1,700 years ago or so. The author of that report wrote, "Their teeth were perfect, even the old people. Clearly, they didn't have sugar in their diet." They were also more physically fit than people in colonies of the same era that were closer to the trade routes and could get abundant sugar.
All this is background for Chapter 9: "Diet Soda". Diet soda is well-hated by some. Sugar substitutes (there are 3-4 found different ones in packets on the tables of most restaurants I visit) are all tarred with two brushes, "Causes cancer" and "Promotes diabetes". The fact is, neither is true. All the "studies" on these were done in rats. To speed things up in cancer studies, researchers use strains of rats that are prone to getting cancer. Let's say a study shows that, of rats fed regular stuff, 5% get cancer in one year; of those fed the same food with some sugar substitute added, 7% get cancer. Both these rates are incredibly high compared to human cancer risk for a typical year. But it "justifies" someone saying, "Sweetener X increases the chance of cancer 40%!" (7/5-1 = 0.4 = 40% increase). They never, ever mention that the amount of Sweetener X given to the rats was comparable to you drinking 400 cans of diet cola every day...for a year. I think the rats really died of disgust!
Dr. Carroll's conclusion, after discussing what is really known about sugar substitutes, from Stevia to Sucralose, is that too little is known as yet. However, if there are risks, either of cancer or diabetes, no human trial has been done to figure it out. None ever will be, because you can't pay someone enough to eat a heaping tablespoon of Sucralose (or whatever) every day for a year or more. In concentrated form, it is awful! There is probably an ethics question also. So the follow-on conclusion is that if there are risks they are small, while the risks of excess sugar are very real and much better known. So he lets his kids have a diet soda from time to time. The rest of the time they drink water, except prior to weaning, when they drink milk.
One bit of almost accidental wisdom came from the Federal Government in recent weeks. They proclaimed that it is OK to drink as much as four cups of coffee daily. Wow! I though it was a big deal, a few years ago, when they said, "up to a cup or to, not more." Before that, it was, "The less coffee, the better." But the studies have been done, with enough quality to convince the FDA folks, so they have this new statement.
A final note: Alcohol is a problematic substance. It turns out, a man who drinks 1-2 ounces of the stuff daily, in whatever form, is in the "sweet spot" for living just a tad longer than those who don't drink at all, or those who drink more than that. Women, being proportionately smaller, can have up to one ounce. But for some, that first ounce leads to a second, then a third. So if you are drinking, keep it moderate. If you are drinking less than that, don't increase it. If you aren't drinking at all, don't start. But if you are drinking more, a shorter life will be the price you pay. Of course, maybe that's the life you want, anyway. Just don't drive afterwards, OK? Alcohol and table salt share this characteristic: there is a "sweet spot". With salt it is more dramatic. For most of us, the sweet spot is 4-7 grams daily. Ingesting 3 grams or less is as bad as getting 10 or more. Your body needs the elements in salt (sodium and chlorine) to live. Without any, you die, and soon. So this final point is, as with salt, so with many foods. Too much is probably bad. Too little can also be bad. Find the sweet spot, and you'll be the best off.
Dr. Carroll also hosts the YouTube channel Healthcare Triage.
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