Diets Revisited -- Two Point Five Year Follow-up

My plan has been to return to the issue of weight and diets once a year. But an excellent article in the New York Times by neuroscientist Sandra Aamodt encouraged me to do my next follow-up after only six months.

My personal data are consistent. I clocked in at 186 this morning so we’re keeping the weight at the same level as the last posting. I am also slowly becoming an even rarer case than I originally thought. My original review of the research led me to conclude that roughly 5% of dieters kept the weight off. The results of the newer studies that Aamodt reports reveal that less than 1% do — though her analyses looked at weight after five years, a longer span than in most of the earlier studies.

Aamodt’s model of weight loss and gain is based on the same general mechanisms I identified back in my original post. When you go on a standard diet your metabolic system detects that there has been a drop in caloric intake and makes neurobiological adjustments. The primary shift is to increase the body’s digestive efficiency so that it can survive on the reduced caloric intake you’ve imposed on it. As a result the dieter feels hungry during the diet. Most dieters just live with the unease because the weight loss is satisfying and, in their minds, it’s worth the pain.

The problem comes when the target weight has been reached and normal intake is resumed. Now the body’s more efficient metabolic system results in weight gain and, of course, it typically goes past the previous high levels. Aamodt also notes that the increased efficiency can be so effective that weight can go back on even when daily calories are kept low.

In short, diets don’t work. In fact — and this is the primary point of Aamodt’s essay and her recent book (Why Diets Make Us Fat: The Unintended Consequences of Our Obsession With Weight Loss) — they almost invariably end up causing weight gain along with the unhappy health and medical consequences.

What she recommends is, “mindful eating — paying attention to signals of hunger and fullness, without judgment, to relearn how to eat only as much as the brain’s weight-regulation system commands.” She also notes that recent research shows that being mildly overweight isn’t a health hazard and that making a psychological adjustment to accept and, indeed, revel in one’s natural body is a good thing to aim for. She’s also, like everyone else in this game, a fan of exercise.

I have no problem with any of this. It’s part of my weight loss regimen. But there are two things she didn’t deal with in the Time’s Op-Ed (she may in her book — I haven’t read it) that I think are critical in keeping weight down.

First, she didn’t deal with the way in which the weight comes off. Most diets (in fact, almost all) have you on fairly sharply reduced caloric intake which leads to fairly rapid weight loss. This is what produces the neurobiological compensatory mechanisms to kick in.

There’s a simple gambit to prevent this: trick your body by reducing your intake by a very small amount over extended time. When I went my original “diet” I aimed for a weight loss of roughly 1 to 2 pounds a month. To do this I only needed to eat slightly smaller portions, eat them more slowly savoring the food and be more mindful about the meal. This technique allows your neurobiological mechanisms to continue operating in their normal manner without triggering off any of those evolutionary mechanisms that are geared to protect us during periods of famine and drought.

Second, she didn’t touch on what I think is the simplest method for keeping the weight off. Weigh yourself every day. Even when you’ve “tricked” your metabolic system into not noticing that you’re dropping pounds the weight can creep back when you’re not looking.

So, look. I get on the scale every morning and spot a gain of a pound or two right away. There’s always natural variation of a couple of pounds up and down owing to lots of different factors but if I hit something like 189 or so I reduce intake and focus more mindfully on eating. Within a day or two I get back down to 186 or 185, my original target.

And, should anyone care, there’s also been no change in my position on deities.