Staying healthy

 

These are some of my personal musings on the topic:

1. Above all, eat healthy and try to control your weight. What that means in practice, is a bit controversial and I will return to that below.

2. Don’t smoke. It has been anticipated since the 1930s that smoking causes cancer [1] and it has now been confirmed beyond reasonable doubt.

3. Don’t take drugs. Don’t drink too much alcohol. Take vaccines, at least the ones recommended by your government.

4. Exercise. What kind of exercise is the best? They say that to live long, you need exercise which elevates the heart rate for long periods of time, i.e. aerobic training, i.e. cycling, jogging or at the very least, walking. But I have seen several headlines which say that for old people, muscle strength predicts very strongly non-morbidity and longevity. So, it seems that to live long, you need aerobic training, but to live even longer, you need strength training, e.g. gym of crossfit. Ideally, you would combine these two types of training in your weekly routine.

So, what is healthy eating and weight? For weight, you would say that having a BMI somewhere between 18.5 and 25 is nice. However, the lower end sounds really low to me and I doubt a little bit if a person with BMI 18.5 can do heavy physical work. Moreover, it’s worth emphasizing that underweight exposes you to osteoporosis, especially in lack of exercise. We all know the perils of overweight.

You can control your weight with many kinds of diets, but which one is the best? Over and over again, when I read the health news, they have the same message: you should eat a vegetable-rich diet which has as little hard fat as possible. Yet there are people who believe in different kinds of meat-rich diets, often because they find easier to control their weight by eating a lot of meat and eggs. It may be that these foods give you an easy feeling of satiety, but what about the vascular health? It may be that you are slim and die of heart failure anyway.

One thing I often hear from these people is that ”people are cavemen, we are not evolved to eat grains” and hence, they ”must” eat a lot of meat. This is actually a non sequitur. Even if we were not evolved to eat grains, it doesn’t imply that we should eat a lot of meat. The best guess is vegetables, tofu and fish.

Even the very truth value of this caveman theory is questionable. Agriculture has been invented aeons ago. Say, it was introduced in your country 2,000 years ago. That makes maybe 2,000/25 = 80 generations. The biologists know that strong evolutionary adaptations can happen in as little as 10 generations if there is sufficient selective pressure [2]. I would say that the availability of (relatively) plentiful, high-energy protein is a strong selective pressure. (Yes, grains do contain protein.) Thus, I would say that people are genetically adapted to eat agricultural food, not paleolithic food.  


References

[1] Thun, M. J. (2010). Early landmark studies of smoking and lung cancer. The Lancet Oncology, 11(12), 1200.

[2] Roff, D. A. (1997). Evolutionary Quantitative Genetics. Springer. See e.g. google books. 


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