What Causes Weight Gain and Why Do We Think Psychology Is So Crucial?
What causes weight gain? Ask the typical modern nutritionist and he'll tell you that ultimately it boils down calories. When we take in more calories than we burn off, we accumulate fat. That's all there is to the story. Calories count. A calorie is a calorie is a calorie.
This website advocates for a converse explanation about why we get fat, the Lipophilia Hypothesis.
Caloric Balance tells us psychology is crucial.
Lipophilia tells us physiology is crucial.
So what causes weight gain? Is it a defect in our brains or our bodies? Consider these points:
1. Men and women fatten differently:
As Gary Taubes (the science writer who renewed interest in Lipophilia) has pointed out; men get beer bellies, whereas women get fat thighs. Postmenopausal women fatten in different ways than do premenopausal women. These observations all suggest that non-psychological factors regulate our fat tissue.
2. Older people are more predisposed to obesity and overweight than are younger people:
But why? Why do we develop beer bellies, double chins, and flabby arms when we get into our thirties, forties, fifties and sixties; whereas when we're in our teens and twenties, we don't these see problems as commonly? If obesity is purely a behavioral phenomenon, then wouldn't this imply that older Americans are therefore LESS able to control their impulses than teenagers. Does that make any sense? Are people more sober minded and restrained at age 55 or at age 15? The answer is obvious. Nevertheless, if you stacked America's 15 year olds next to America's 55 year olds, the 15 year olds would, on average, be slimmer and healthier. Why? If we believe that obesity is a psychological phenomenon -- that we get fat because we're gluttonous and lazy -- how can you explain this? Do 55 year olds "overeat" compared to 15 year olds? That can't be true. Then what causes weight gain preferentially in older people?
Perhaps 55 year olds get less activity than 15 year olds. That makes more sense. But can this activity difference really account for the abundant discrepancies in fat composition of these two groups?
What about the evidence that exercise over the long term doesn't lead to weight loss? And what about 55 year olds who work out like crazy but can't lose the spare tire? And what about all those 15 year olds who sit around munching on snacks and playing videogames all day who somehow remain thin as string beans? What's going on? Even if you can prove that 55 year olds as a class exercise less than 15 year olds do, in order to support the Caloric Balance Hypothesis, you must show that every single case of obesity or overweight can be blamed on gluttony and/or sloth. After all, Caloric Balance tells us that only two variables "count" -- "calories in" and "calories out."
3. Genetic differences. Identical twins tend to fatten in exactly the same places, as Gary Taubes has pointed out:
Clearly hereditary and hormonal mechanisms must be controlling how and where people put on fat. Indeed, we all accept this idea that some people are genetically predisposed to get fat. People admit to having common "problem areas" on their bodies -- like fat arms or big butts. Different people have different fundamental body shapes. But these observations do not square with the theory that "calories count." We're taught that our fat tissue is essentially a piggybank for calories. We put coins into it (e.g. calories in), and we take those coins out (e.g. calories out). What causes weight gain is when our calorie accounting gets out of whack. Genetics, hormones, enzymes, etc are beside the point and have no say in the matter.
Caloric Balance theory provides no explanations for why identical twins fatten identically, why some of us get double chins while others get big butts and others stay lean as a bean. It tells us nothing.
And yet somehow obesity researchers and public health experts have managed to overlook this avalanche of contradictions about what causes weight gain. They publish thousands of articles a year about different ways in which hormones and other physiological mechanisms regulate obesity and overweight. But when they talk about trying to "lose weight" -- which is essentially trying to re-regulate our fat tissue -- all they seem to talk about are "calories in" and "calories out." Why?