One of the fundamental attitudes towards food most people have that I want to change is that it's fuel. I remember the movie Barfly, based on the writings of Charles Bukowski, where Mickey Rourke (as Bukowski's literary persona, Henry Chinaski) is rampaging through his run-down tenement building looking for a ham sandwich as he shouts, "I need fuel!" Well, that sickly, hungover, pot-bellied vision of humanity is apt, especially when people think of food as equivalent to gasoline.
But food is not fuel. Food is nourishment. When you put gasoline in a car, does the car integrate the gas into its body? Does the car metabolize and repackage the gas into new compounds that integrate themselves into the makeup of the car itself in order to keep it alive? Does the car grow and generate new tissue based on the gas it ingests? No. Because a car is a machine. The human body is not a machine, it is alive, and the food it eats is alive.
I can rant on and on about how the calories in calories out paradigm of nutritional thinking is flawed, but many other paleo bloggers have done it better already, so I won't bother. The point I'd like to drive home is that not all calories are created equally. If food were merely fuel, you could just eat 2,000 calories of anything at all and be done with it. It wouldn't matter at all what you ate, you could just down glasses of sugar water for sustenance, and stay healthy forever. But what sane person believes that you can do that? Obviously, what you eat - the quality of it, the way it was grown or raised, its freshness, and its compatibility with the human body - is way more important than how much you eat. Think long and hard about this, would it be better or worse to eat 500 calories of steak or 500 calories of high fructose corn syrup? Would it be better or worse to eat 500 calories of fresh vegetables or 500 calories of white flour? Even if you're not paleo, I think you intuitively know which choices are better.
So why are healthy foods better? Is it because of how much starch relative to protein they have? Is it the amount of fat or the lack thereof? Well, here's the other piece of the "what is food?" puzzle that I'd like to address. Nutritionists and even paleo people are way too stuck on the macronutrients we ingest. Macronutrients, for those who don't know, are fat, protein, and carbohydrate, the three main categories of food we eat. A sweet potato is carbohydrate. Table sugar is carbohydrate. Does this mean they're the same when it comes to our bodies? Gluten is a protein. Tuna is protein. Butter is fat. Margarine is fat. Is it all the same? Obviously not. I won't even get into talking about how micronutrients (minerals and vitamins) are more important because there are also those that think we can isolate the micronutrients and take them in pill form. We are only barely even beginning to understand how various nutrients work in concert in whole foods, and we are still discovering new vitamins and nutritive and antioxidant compounds in our food, and many supplements are turning out to either be ineffective or even downright unsafe. Why would you take resveratrol (which hasn't been proven to do anything in isolation) in pill form rather than just having a glass of red wine? Makes no sense.
Let's talk about T. Colin Campbell's book The China Study which contends that animal protein causes cancer. The vast majority of the research that his argument was based on was founded on studies that fed isolated casein (a protein in dairy) to rats, thereby inducing cancer. Forget that mice were never evolved to eat isolated dairy protein and that their casein chow also contained sugar, grains, and other processed food, but whey protein, another dairy protein, has been shown to reduce cancer. Therefore, whole milk seems to have a neutral effect on cancer.
Another example is fish. People make a huge deal about the mercury in fish, but studies have found that the presence of selenium in fish binds to the mercury, thereby making it harmless to humans. Therefore, most commonly available fish is safe for humans with regards to mercury. Fish with lower selenium levels, such as shark and swordfish, are more risky to eat because the mercury in their bodies exists in a much more toxic state. Also, people make a big deal about PCBs and dioxins in fish, but in reality, all other food is more likely to contain those toxins. Eat fish.
My point is that we're too reductive in our thinking about food. We're too focused on what food does and doesn't contain - the pollutants, the additives, the isolated compounds, macronutrients - that we lose sight of what real food actually is. Don't get me wrong, it's important that our food isn't polluted, but it's also important not to be so paranoid about it that you're avoiding real food. Think about it this way: food is sunlight, minerals, and chemicals packaged in such a way that our bodies can absorb and integrate into our cells to help us stay healthy. That's it. Stop worrying about how much red meat you're eating or how much shellfish, or how many naturally nitrate-laden leafy greens. Just eat real food.
