Fast or Slow Weight Loss? (November 6, 2014)

The conventional wisdom for ages has been that you ought to lose weight slowly because it stays off longer. But now that someone has decided to actually test whether or not that’s true, it turns out not to be the case.

A study from the University of Melbourne found that 81% of the people who went on an extreme 12-week weight loss diet hit the given weight loss goal, versus only 50% of those on the more moderate 36-week diet. (That goal was a weight loss of 12.5% or more of the participant's current body weight. For someone 155 lbs, and I'm not saying why I picked that particular number, that would be about 20 lbs.)

Moreover, three years later, about 71% of the weight had been regained. But the slow losers were no more likely to have kept weight off than the fast losers.

Why have we always assumed that losing weight slowly is better than losing it quickly? My guess is that because people who lose weight by changing the way that they eat seem to be more likely to 1) lose their weight slowly and 2) keep it off for longer than people who lose weight by other means. Plus we've all seen people do something like eat celery for a month, lose 35 pounds then gain it all back. So because it was "logical", no one really bothered to look at this more closely until now. But human logic isn't always the body's logic, and this seems to be one of those occasions.

Next week I'm planning to write on fasting, for weight loss and for health generally, and I'll go into more detail on the subject of rapid weight loss then. But right now I'd like to mention that for many years I have thought that the best way for most people to lose weight incorporates both these methods to some degree. The Scarsdale Medical Diet includes very low carbs with large quantities of fruits and vegetables and lean meat, and weight loss of up to 20 lbs over a two-week period is not uncommon. Plus the creator of this diet, a cardiologist named Herman Tarnower, was 69 years old when he was murdered by a jealous girlfriend, and I cannot think of a better tribute to the health-giving properties of his diet than the fact that, at 69, he was clearly still lighting up the ladies.

--dr. diane holmes
  Copyright © 2014