Approaching nutrition from first principles
Let’s take the physics approach to nutrition. Physicists like to take a cow and go “let’s model this as a perfectly round sphere of a given mass”. Let’s do something like this, but for people: imagine your body is straw. You have food coming in one end and something else coming out the other. The straw has all sorts of mechanical processes in it that turn food into more straw. A healthy straw stands tall and firm. A sick straw slouches, metaphorically speaking.
Atoms
On the most basic level, how do we decide what we should eat? We do need our Vitamins, our Omega-3 fatty acids, etc but that’s already too high level. We’re gonna start from rock bottom and quickly take off from there. So… what atomic elements is your body composed of?
You can see that the top 3 elements make up 93% of your body mass. The top 5 make up 98%. Suppose someone comes along with a diet that someone manages to not include any phosphorus. You’ll know to discount it. Chances are, most diets will pass this test, but you get the idea. You might go “I don’t like greens” until you realize the chlorophyll molecule that gives greens their color has magnesium right in the center (Mg):
A salad on its own is cool. Clearly lots of magnesium in there. But what’s important is not salad eating per se, but that your body is getting magnesium. You can also eat chocolate to get it. Lots of different foods have magnesium. What matters is that you cover all your bases. It doesn’t matter how you do it (well, it does matter a little). Your body knows how to extract magnesium from chlorophyll, but that doesn’t necessarily mean it can do the same if you swallow some magnesium shavings. And then where does this magnesium go? Does is just get diluted evenly throughout your body? Probably not. Magnesium is mostly in bone and muscle. And what happens if you don’t eat it…
Now how would we even know that the above is the case though? It’s not too complicated. You put people into two groups and one group gets magnesium and the other doesn’t. Both groups have their magnesium levels tracked. At least, that’s the experiment I’d like to have performed. I follow the link to their study and it turns out this is not what they did. They observed magnesium levels along with other things and showed a correlation over the course of a few years. Interesting, but there’s a good chance people who don’t eat their greens could be missing other things as well. In short, they haven’t proven that adding magnesium shavings to my diet is gonna cure my depression. But what this study does tell me is that people that eat healthy foods (likely greens) are less likely to have all sorts of issues. But they do have a story where a mentally ill guy defecated on a bed because it “smelled nice”. Psychiatrists couldn’t help him, but they gave him magnesium and “these manifestations disappeared".
Molecules
This brings us to the second pass when it comes to foods: molecules. Your body is a machine. Imagine your body as a straw again. Imagine that the inside surface is like a conveyer belt that takes the food you eat and turns it into more of you. It’s sort of like an assembly line.
Imagine a car assembly line. Now imagine you keep getting rubber shipments. This would be useful if you had machinery in the factory to turn rubber into tires. Imagine a neighboring factory making fun of you for not being able to process rubber into tires and belittling you as a “disabled” or even a “diseased” factory for being incapable of producing cars with wheels. Maybe nothing is truly wrong at all, you just need a different “diet” of shipments. The entire problem would be fixed if you got shipments of tires as opposed to rubber.
In the northern US, a lot of blacks have low Vitamin D levels. It’s not that their bodies can’t produce it, it’s that their bodies are optimized for a sunnier environment. As you age, it’s common to lose the ability to metabolize lactose. It’s like having a car factory that runs on solar being uprooted and placed in an environment where the sun hardly comes out.
Some people are SUVs. Others are Mini Coopers. Some come with 4 wheel drive while others don’t. Some are high performance, high maintenance machines while others are indestructible and adaptable. What you need and what others need may be different. You might have some internal machinery to turn rubber into tires. Your neighbor might not. So, advice that works for you might not work for your neighbor.
What makes humans different from cars is that when you scrape a car, it stays that way, but when you fall and scrape your knees, you heal. Humans are like the car and the car factory all rolled into one thing. Imagine if you take your car to the gas station and the pump has more than just gas, but little bits of rubber that the car uses to replenish the tread on your tires. Human fuel isn’t too far off from this description. If you eat a bowl of pasta, most of that is carbs (pure fuel) along with trace amounts of vitamins and minerals.
So, your body needs nutrients, and some of these need to be topped off regularly. For example, you need Sodium and Chlorine. This usually comes in the form of salt (sodium chloride) and you sweat it out. Others take a while to draw down. The common way to distinguish them is fat soluble vs water soluble. What makes “fat-soluble” vitamins special is they tend to stick around for months and are stored in your body’s fat.
As you’d expect, your body knows how to feed itself to an amazing degree. Why does colorful food look tasty? We went over how green = magnesium. But also, orange/red = Vitamin A. Store-bought tomatoes don’t look as appetizing as home-grown, and for good reason. Your eyes aren’t deceiving you. The one on the right tastes better and is better for you.
When it comes to food, just going for low prices is good as long as you’re getting all your nutrition. Some foods are worth the extra price. Others aren’t worth the bargain. Imagine getting a tire shipment to your car factory, but each semi-transparent crate of tires has half the tires you normally get. You might be getting a bargain if you’re counting the crates, but you not so much if you’re counting the tires in them.
If you feel hungry after eating what you think should be “enough”, then it’s time to do some investigating. The food probably lied to you. It probably lured you in with promises of fulfillment only to leave you hanging. They gave you empty crates and left you wanting more.
Cells
Tiny micro organisms line your gut. Think of them as machines that sit inside the straw. I don’t know much about them. The microbiome is important. Some people do fecal microbiome transplants if they believe their biome was disrupted by antibiotics or poor diet.
Unknowns
We went over atoms and molecules, but until scientists can give you a feeding tube with a better balance of nutrition than what you can get through food, I think we shouldn’t dismiss the value of traditional foods.
The above image shows a lot of the biochemical pathways we already know about. What it doesn’t show you are the pathways we don’t know about. What we know for certain is that our ancestors lived to reproduce. The best way to ensure your own health is to eat exactly what your ancestors ate, and even this will come with pitfalls. For example, soil today isn’t the same as it was back then. Hell, even the fruits and vegetables we know and love have been ruthlessly genetically engineered for centuries even before we gained the ability to genetically engineer our foods.
Agriculture is international too. Regardless, the plants you eat won’t grow unless certain prerequisites are met. In the same way that your body will show signs of illness due to malnutrition, so will the plants. Lots of food has been cultivated to be sweeter. My best guess is that sweetness isn’t the best metric to go for when choosing which fruits and vegetables are the best. Instead, I’d go for strong and distinct flavors other than “sweet”.
Toxins
They say you can catch a lot more flies with honey than with vinegar. Sometimes the healthy stuff you want gets packaged up with something bad that you don’t want.
Plants don’t want to die. Seems obvious, right? But they also can’t run away from predators. This means they need other ways of staving off pests or anything else that wants to eat them. That’s where toxins / lack of digestibility comes to the rescue. All plants will have chemicals in them that are toxic. So it’s not surprising that people will be allergic to certain foods. For example, milk can be good and healthy in moderation, but I was drinking 5 glasses a day and getting massive stomach aches. Until I figured it out it was milk, I had no idea what it could be. It could have been anything. It could have even been a genetic defect, but in hindsight it’s obvious. The same can be the case for many health problems.
Other inputs besides food
Interestingly, both cars and people need oxygen in order to burn their fuel. Our fuel is primarily carbohydrates and fats which are mainly made of carbon oxygen, and hydrogen. Now look at ethanol:
It’s the same stuff! In fact, we can drink this molecule (it’s the primary molecule in vodka). Ethanol-powered engines produce a stinky gas (formaldehyde). Humans also produce a stinky gas (though I don’t know if it’s for the exact same reasons). In fact, ethanol itself comes from plants like corn and potatoes. You put a gasoline-powered car into space and it won’t work; there’s no oxygen. You put a person in space… same deal. So in a forest fire where all that oxygen is being converted into CO2, a gas-powered car will have a hard time getting enough to keep the engine running. It’s also why you can literally choke to death in a fire, even if you can somehow manage to keep yourself cool. My point is, food isn’t the only thing we need to be keeping an eye on. We need to be thinking about the air we breathe.
If your bedroom doesn’t have good airflow at night, then you’re essentially treating that entire space as an oxygen tank that you run down over the course of the night. Before you get freaked out, there’s more to know about CO2. Given all the discussion of high carbon dioxide affecting the environment, I always assumed it made up a big portion of the atmosphere. I was surprised to learn that it’s measured in parts per million. I’ve measured CO2 in my bedroom with the window closed and it goes up to around 2000ppm, which my air monitor says is too high.
Besides optimizing oxygen, you need to avoid the bad gases (like those that come out of cars) and air particulates in general.
Another thing to keep in mind are the materials your body is in contact with. Your skin is a pretty good barrier in general. 80% of the atmosphere is nitrogen, an inert gas that won’t chemically react with your skin. However, oxygen (which makes up about 20%) will interact with your skin and will age you.
Outputs
This about wraps it up when it comes to inputs, but we haven’t even gotten to outputs. At a basic level, we want basic bodily functions to behave normally. People talk quite a bit about weight, but there’s also skin, nails, hair, sweat, and breath too. For example, if you’re asian and you’re following my advice to eat traditional food, you might start substituting your pizza consumption with rice. However, too much rice from a place that has arsenic in the soil can lead to arsenic toxicity and your nails can get these Mees’ lines:
If you wash the rice, you can get rid of the arsenic. But if you’re eating white rice, you might be inadvertently creating another problem: washing away essential nutrients. For example, “High rates of illness and death in overcrowded Haitian jails in 2007 were traced to the traditional practice of washing rice before cooking” (Wikipedia). Yeah, it’s that bad but if you’re eating a varied diet then washing rice isn’t going to hurt you.
Conclusion
To conclude, diet and broader health can be broken down. Hell, you can probably do it yourself. The important thing is to follow a good process of knowledge discovery, which is hard to do given all the people out there espousing their special diets and pills.
What are the molecules (vitamins and proteins) you need? Pay attention to outputs like your health, skin, and nails. Then, look at foods that are cultural staples for you. Find foods that have deep cultural roots. I’m Ukrainian and we love our potatoes, but the buckwheat and cabbage have been staples for far longer. And finally, remember that nutrition can take on a religious quality. It’s so personal. It can be hard to refuse certain foods, or to change your diet in meaningful ways.
One thing I haven’t done (and I’m sort of kicking myself for not doing it) are blood panels to see if there are nutrients I might be missing, or not absorbing for whatever reason.
All together, the human body is incredible. It’s amazing that it works at all. It may feel bad to have some embarrassing symptom that is noticeable to others, but I never really appreciated just how much these symptoms exist to tell us something. My stomach aches weren’t a symptom of my body being broken, but a symptom of drinking absurd amounts of milk. One of the most important things we have is our health. If you have a health problem, you could look at it as a personal hinderance to the things you want to accomplish in your life, or you can look at it as an opportunity to explore one of the most important subjects in the world and contribute a valuable nugget of knowledge that will help future generations indefinitely.
Would you like me to write more on any of these topics in depth? If so, let me know!