For many people hoping to lose weight, low fat treats like ice cream and potato chips are, or at least seem to be, a marvel of modern food engineering.
But, according to some recent studies, fat substitutes like olestra may not help much when it comes to losing weight. In fact, artificially low fat snacks may actually lead to weight gain.
Regular Fat Vs Fat Substitutes
At least that's been the case for rats. In one study, researchers divided rats into two groups: one on a high fat diet, and one on a low fat diet. Then each group was split into two sub groups: the first sub group ate a mixture of regular fat chips, and fat substitute chips containing olestra.
The second sub group ate only regular fat chips. After 28 days, the rats were weighed and examined, and the researchers found that the rats on the mixed diet of regular fat and fat substitute chips were more likely to have gained weight.
Molecules In The Brain
There's no clear cut explanation for why this happens. The researchers suspect that it has something to do with how the body recognizes and responds to fat molecules.
When the brain senses fat, according to this theory, it prepares the body for a heavy calories load and accordingly adjusts mechanisms for regulating appetite.
But when the fat molecules turn out to be low cal substitutes, the system is thrown out of whack. And the brain may compensate by increasing the desire for more calories, leading to overeating.
Of course, rats are not people, and fat substitutes may not affect human appetite in the same way. But they might, and further research will say more about how our bodies respond to fat, real and fake.
- Fat substitutes lead to weight gain: Purdue study (Stone Hearth News)