The Epistemology of Food
One thing I spend way too much time on is food. If you don’t believe me, see my new cooking blog. I’m running an experiment in which I plan to cook 100 meals from cookbooks published by excellent chefs in one year and blog each one of them. I hope to also write about my personal history with food and cooking, as well as what I learn along the way. I’ve actually cooked a lot more dishes than I have posted, I just haven’t had time to write them all yet, but I’m on track.
Anyway, in addition to food I’ve been concerned with diet for quite some time. Unfortunately the more you read about what you’re supposed to eat the more frustrated you get. You come to realize quickly that there are some deep epistemological issues with nutrition. People get their information from a combination of science (good and bad, but mostly bad) and lobbying money, and science funded by lobbying money.
So when I see stuff like this extremely popular article I read recently, Eating Healthy for $3 A Day, in which the author strives to “eat healthy” by using the same USDA guidelines that have led us straight into an obesity epidemic I cringe. He’s using caloric ratios determined by our government and doesn’t seem even remotely cognizant where they come from or what effect they’ve had on the populace over the last 30 years. I hope for his sake this is just a brief experiment.
If you want to read a great article about just one small piece of the dietary puzzle, here’s one from the New York Times in 2002 with the best name ever: What if It’s All Been a Big Fat Lie? It’s about the interplay between science (both good and bad), Dr. Atkins, and government health recommendations.
The short story, and you should know this, is that in the 1970’s a link was theorized between saturated fat and cholesterol. Cholesterol was believed at the time to cause heart disease, so by the transitive property of bad science it was decided that saturated fat causes heart disease. (We now know the cholesterol-heart disease link itself is not that simple; there are two types of cholesterol and one appears to actually prevent heart disease, but at the time it was considered a slam dunk. Unfortunately it turned out to be a slam dunk in the much the way WMDs in Iraq did.)
As a result the government and medical institutions like the AMA gathered together and decided to recommend replacing calories from fat with calories from carbohydrates. Unfortunately it was bad science. The last decade since that article was written has essentially proven that if medicine had the same standards as, say, economics, that link would never have been considered valid in the first place and certainly wouldn’t have become the basis for government recommendations and regulations. Meta-studies have shown no statistically significant impact of saturated fat from meats on heart health. Tons of individual studies have been published with mixed results.
Also there’s a distinct correlation between the switch from fat to carb calories in the western diet and the rise of obesity, diabetes, and heart disease. Hilariously in our attempts to become healthier we did things like cutting out butter, which contains a mix of saturated and unsaturated fats that may in fact be healthy, for margarine which contained trans-fats which, it turns out, are one of the few things we know for sure are really bad for you. We ditched meat but replaced it with preservatives and sugar, largely from high fructose corn syrup.
Interestingly when I talk to people most still believe firmly that saturated fat is unhealthy. My generation grew up hearing that. Two plus two is four, and red meat will give you a heart attack if you eat too much of it. These are things we just accept because we’ve been told that by people who should know. In reality it turns out that, while saturated fat in some quantity may be bad for you, we just don’t know. It may also be good for you. The results are wildly inconclusive. The one thing we do know for sure is that cutting out carbs leads to weight loss, which is a really strong indicator that we’re eating too many of them.
But really there’s a pretty good chance we’ll never know much of anything for sure because diets are zero sum. People have to eat something. If people eat less fat and more carbs and then they start getting sick (which is undoubtedly what has happened in the last 30 years) why is that? Is it because of the reduction in fat, or the increase in carbs, or because some nature-intended balance got thrown off? Is it because the fat came from meat which is also high in protein, iron, zinc, and various vitamins and now they’re not getting enough of those? Is it because most of the carbs comes from prepared foods loaded with preservatives and high fructose corn syrup? Even if they just cut out fat and didn’t add carbohydrates, and assume they can get the rest of what’s missing from multi-vitamins (which, by the way, are statistically proven to have zero impact on health) now we don’t know if they’re getting sick because they’re just not eating enough.
This is the main failing of nutritionism. Science has given us this idea that it’s not about what foods you eat but what nutrients. If we could just get the right combinations of nutrients, we’ve come to believe, we’ll be fine and would be even if we got them from a pill. Of course, scientists also discover a new nutrient multiple times a year. When I was a kid nobody knew what lycopene was. Now every bottle of anything containing tomatoes is touting its benefits.
So if you want to think about diet, you have to do it holistically. You have to think in terms of what foods the human animal is designed to eat. There are a few ways to do this.
First, you can look at remote tribes of people who haven’t been told about things like carbohydrates and saturated fat. What do they eat, and, when you control for the many causes of death they suffer from that we don’t, are they healthier? As bad as carbohydrates may be for you, a guy who eats bean burritos and ice cream all day is still going to live longer than a guy who gets his water from a river.
It turns out they eat lots of two things: green vegetables and lean red meat. Interestingly, they eat them in vastly different quantities. Some tribes are almost all gatherers, some eat almost no vegetation, and most are somewhere in between. They don’t eat preservatives. They’ve never heard of sodium benzoate. They don’t know what bread is. Their diets actually look a bit like Dr. Atkins’ recommendations, though without all of the silly phases. When you’ve never even heard of rice or ice cream it turns you don’t need very many rules.
The human body is remarkably flexible when it comes to diet which is, undoubtedly, one of our most significant adaptations. In fact this is a second way we can figure out what we should be eating, by comparing ourselves to similar animals. Our teeth and digestive systems are a perfect hodgepodge of carnivore and herbivore. Both are clearly able to process large amounts of both meat and vegetables, which is not common in the animal world. The size and nutrient requirements of our brain indicate we’re meant to eat at least a decent amount of meat.
I think the best you can do, really, is to not overthink it. The human body is remarkably resilient; small quantities of anything are unlikely to have long-term negative effects. Stay away from processed foods and you’ve already taken a big step. Try to reduce carbohydrate intake, but don’t worry too much about eliminating it. If you’re out at a nice restaurant then sure, have a little bread and maybe a desert, but don’t keep it in your house regularly.
Just keep your calories low and stick to food that is, well, food. Avoid eating things humans were clearly not designed for, like refined carbs and preservatives, and just accept the fact that beyond that you’ll never really know what you should or shouldn’t be eating so save your brainpower for the stuff that can make a difference.