Recent research indicates that after you have  lost weight, you have an increase in your emotional response to food. The research also indicates a decrease in  activity of the area of the brain that is  involved in restraint. One of the hormones that play a role in controlling appetite in the body is called leptin.  After significant weight loss, leptin levels drop. This seems to signal to the brain a need to seek more food.

In a recent study, overweight volunteers followed  a calorie-restricted diet aimed at shedding 10 percent of body weight. Using MRI scans, the researchers looked at changes in how the volunteers’ brains responded to seeing food after weight loss. Leptin levels dropped and there was more blood flow to areas of the brain known to be involved in the emotional control of food intake. Lowered leptin levels signal the areas of the brain associated with reward-seeking .

This evolutionary programming is out of sync with what is healthiest for our bodies today. The signal evolved over thousands of years when food was scarce. It was the brain’s way of telling the body to seek food and protect fat stores. Many people, particularly those who are prone to gain weight easily, have retained more genes that program us to seek food.When the researchers restored leptin  by giving injections of the hormone, the brain response changed. With leptin levels restored, there was more activity in brain areas associated with conscious decisions.

This adds evidence to the fact that crash dieting, or severe restricting  of food intake for extended periods of time are not productive methods of weight loss in the long term. So, until the pharmaceutical industry invents a drug that can stimulate leptin signaling , our best option is to make small changes to our habitual energy intakes and aim to lose weight in stages, not all in one go! Patience is key.