Bikini body!

With summer approaching, the catchphrase for women is "lose weight". In the next few weeks, as happens every year, the sale of diet foods and weight-loss supplements will increase. A variety of products will sell: diet shakes, herbal teas, and detox juices. For scientists like myself, the real question is: what actually works?

When considering diets, there is one inescapable truth: if you reduce your eating enough, you will eventually lose weight. The science behind this is simple: we accumulate fat on our bodies to store energy. This fat only accumulates when we consume an excess, bringing in more energy than our body needs. Once the fat has accumulated, the only way to get rid of it is by expending more energy than we consume, creating an energy deficit.

Exercise is, of course, one way to create energy deficits. The problem with this strategy is our bodies are very reluctant to give up stored energy. When we exercise, our bodies often compensate by getting hungrier in an ef fort to recover the extra energy we are losing. So whether you exercise or not, hunger becomes of central importance for any successful diet program.

There are two basic types of hunger: homeostatic and hedonic. Homeostatic hunger is the natural process in which our bodies detect we need more energy. This hunger arises in a complex process not fully understood but involving at least several hormones. Hedonic hunger, on the other hand, is hunger that arises from cravings. Functionally speaking, the main difference is hedonic hunger involves the desire for a specific food whereas homeostatic hunger involves a general desire: when you have homeostatic hunger, you can eat anything.

Hedonic hunger is a fairly new concept and still poorly understood as a biological process. The idea goes humans evolved this process to take advantage of moments when food was plentiful. This would make sense in primordial and ancient times when food was not always readily available. In these sit uations, hedonic hunger may have been a mechanism that allowed us to fatten up in anticipation of food scarcity (like bears eating voraciously to fatten up for winter). The problem is modern humans generally do not suffer food scarcity anymore, making hedonic hunger an outdated mechanism for survival.

Unlike homeostatic hunger, hedonic hunger seems to involve a strong psychological component. Cravings can be brought about by a variety of external triggers, the most common being the sight, sound, or smell of food. Think about the sound of steak sizzling on a grill. That hunger you feel is hedonic. Hedonic hunger can be viewed as one of the greatest barriers to a successful diet. Not only does it contribute directly to the process of weight gain (by motivating us to eat more than we need), it also functions as an urge we have to fight when trying to lose weight.

So how do we defeat hedonic hunger? A good amount of research has indicated mental focus plays a big role. Ever work all night or play a video game all day only to realize you were famished? Such experiences clearly illustrate how focusing on an immersive mental task can keep hunger at bay. Recent research from Plymouth University has even demonstrated playing Tetris can stave off cravings.

Another effective strategy involves avoiding the presence of food. A variety of research has shown close proximity to food can entice people to eat more. By removing these temptations, hedonic hunger is less likely to trigger, making for a less painful dieting experience.

The content of what you eat also matters. Not all foods give our bodies the same level of hunger satisfaction. Foods that are high in either fiber or lean protein are the most satisfying, even though they might not be high in calories. Highly processed foods, on the other hand, like ice cream or potato chips, are high in calories but low in hunger satisfaction. So the bottom line is: control your hunger to get that bikini body .

The writer is a Ph.D. from Yale and a professor at Dongseo University in Busan. He is also the associate director of the Tan School of Genetics at Fudan University, Shanghai. His email address is jfendos@aya.yale.edu.

Source: Bikini body!