Wednesday, August 12, 2009

TIME Cover: Why Exercise Won’t Make You Thin

time-cover I saw this cover story today on a Time magazine in a waiting room:,8599,1914857-2,00.html.  The subtitle on the paper copy was a bit more intriguing: “The Myth About Exercise. Of course it’s good for you, but it won’t make you lose weight. Why it’s what you eat that really counts.”  (emphasis mine)

Could it be that the science behind our Paleo/Primal/Atkins approach is finally going mainstream?  I just read a line last night in Hunter Thompson’s book about Hell’s Angels where he has something to the effect of “Publication X tries to propose new ideas whereas magazines like Time are more about capturing and documenting the conventional wisdom of the current time.”  So if Time magazine does a cover article about what you eat being more important than how much you eat, that would imply that this line of thinking is going mainstream. Yay!

But is that what they’re really saying, or did they have a different perspective?

Main points that I see in the article:

  • Exercise has other health benefits other than weight loss.  Regardless of what the author says about obesity, he is not denying that exercise helps reduce risk for heart disease, diabetes, cancer, … cognitive function in the elderly, chronic back pain,
  • In a recent clinical study of 464 overweight women, exercise didn’t influence the amount of weight lost.
  • He talks of two types of “compensation” – eating more or reducing activity at other times in the day.  (This is very consistent with my understanding of caloric balance, eh?)
  • He still thinks a lot in terms of caloric balance, i.e. “… you would be able to eat only an extra 40 calories per day, about the amount in a teaspoon of butter, before beginning to gain weight.”
  • Humans fatten more easily than other animals because we have very little “brown fat.”
  • A study in Plymouth, England, found that youngsters at three different schools expended about the same amount of energy in spite of having widely varying amounts of organized activity in PE class. (This is also consistent with my understanding of caloric balance.)
  • He implies that organized/planned/structured exercise stimulates your appetite whereas other activity (which I would call NEAT) does not.
  • In a diabetes study, a healthy body mass index is more important than being aerobically fit.
  • He even mentioned Taubes at the end!

But the only advice that he provides on losing weight is “eat less.”  How can you mention Taubes and still push for caloric balance??  Despite the subtitle, he never talks about what you eat and the influence that this has on fat storage and use.  I was disappointed but not surprised.

He mentioned that caloric consumption tends to be proportional to energy expenditure.  This seems to contradict caloric balance theory.  So I think that there is room for an excellent follow-up article that goes into why some people attain unhealthy weights and what approaches can work to get them back to a healthy weight.

I continue to believe that insulin resistance by far the most common cause, affecting 80-90% of obese people.  Let’s see an article about that in the mainstream press!

1 comment:

  1. Hi, Chris! I liked your comment on Mark's blog and thought I'd check out your blog. Insulin resistance is definitely a problem, but there are also psychological issue, all of which are actually worsened by the current mainstream treatment options for obesity!