Hi Heather,
Thank you for the thorough and thoughtful comment. I appreciate your interest in the discussion and didn’t feel that you were just trying to prove me wrong. I find respectful disagreement stimulating.
First of all, we probably all agree that nutrition is a complicated topic, with health outcomes determined by many competing variables, and I don’t think anyone has a perfect answer. That’s part of why I think personal experimentation is so important. In the end, every individual has to decide for him or herself what will lead to good health.
You point out that there is no proof that being overweight leads to health problems, only correlation. That may be the case (or not–I don’t know for sure), but there is a lot of evidence of this correlation, and it exists for multiple diseases and disorders. I will speak from experience: When my BMI exceeded 30 for the first time, I noticed increasing blood pressure and shortness of breath when performing normal day-to-day tasks. Now that my BMI is falling, my blood pressure is returning to normal and my breathing is improving. Personally, I think it is risky to discard the medical consensus that obesity is unhealthy, but again, it is an individual decision.
I felt a certain one-sidedness in your response. You are critical of my position because I can’t prove my point without a shadow of doubt, but Matt’s overfeeding theory is itself conjectural. I respect that it is one way to read the evidence, but it is far from proven.
My point in mentioning thyroid and stimulant drugs was to provide support for my position that I did not have an abnormally low metabolism. Metabolism may be more complicated than this, but then how do you propose to measure it? Temperature is also a simplification, and temperature can be manipulated without improving health. To really measure BMR, you’d have to go to a hospital and pay for an expensive test. I remember watching a documentary about weight (The Weight of the Nation, I believe), and a woman had her BMR tested, insisting that it was low because she was eating so much less food than her thin friends. It turned out it wasn’t low at all, but that she was simply eating more than she thought. Obese people tend to underestimate how much they eat, just as people with anorexia tend to overestimate. I think we are probably even more inaccurate when we try to estimate any abnormality in our own BMR.
It’s true that starvation or extreme dieting will lower BMR, but I don’t believe this explains our nation’s obesity epidemic. Americans eat more than we used to, and we are bigger than we used to be. We also engage in a lot less physical activity. I don’t think the obesity epidemic is a mystery, and other countries are catching up with us–and in fact Mexico just took the #1 spot recently.
I understand your point about a tall person with a proportionately higher BMR, but my point was that, simply by gaining weight, we automatically increase our BMR. This isn’t a controversial point. If I put on 50 pounds, my body will produce more heat in order to fuel my extra mass. Muscle requires more energy, but fat requires energy too. Obese people tend to have higher BMRs than thin people, which is why they have the potential to lose weight more quickly. However, a high BMR isn’t necessarily a good thing.
At this point, the benefits of exercise seem obvious to me, and I think I’ve made my point elsewhere in the thread, so I won’t go into all the benefits again. However, I disagree when you say that exercise doesn’t induce relaxation. I find the chemical response after a jog to be very relaxing as long as I don’t overdo it. As an example, over the last couple of days I had to give a couple of long presentations, and in the past I would get nervous beforehand. However, my morning work-out left me feeling calm and confident, and I had no nerves at all. I am only speaking from personal experience, but that’s because that’s the only area I can claim expertise.
My theory in this thread was speculative, and I’m open to the possibility that I might be wrong. However, what I do know is that my health declined due to overfeeding, but I still felt good mentally. I am looking for a resolution to that paradox. I have other theories, but maybe I’ll present that as another thread at another time.