Cocaine users 'thinner' because drug alters metabolism

Metabolic alteration explains why users gain weight during recovery

Using cocaine can dramatically alter metabolism, a new study has found.

Cocaine users are often thinner when using the drug, a study published in the journal Appetite has suggested.

Previously it was widely assumed that cocaine use led to weight loss because it suppressed appetite.

Now, new research led by study leader Dr Karen Ersche, from Cambridge University, has shown that the weight loss was due to "a profound metabolic alteration" that would need to be taken into account during rehabilitation and treatment. Weight gain during recovery can be dramatic and lead to relapse.

“We were surprised how little body fat the cocaine users had in light of their reported consumption of fatty food. It seems that regular cocaine abuse directly interferes with metabolic processes and thereby reduces body fat. This imbalance between fat intake and fat storage may also explain why these individuals gain so much weight when they stop using cocaine.”

Researchers studied the body composition, diets and eating habits of more than 60 men, half of whom were dependent on cocaine.

Cocaine users showed they had developed a preference for fatty foods and carbohydrates, and also displayed patterns of uncontrolled eating.

Despite this, they often experienced weight loss and had significantly less body fat than non-users.

Men taking cocaine also had low levels of the hormone leptin, which inhibits appetite. Low leptin levels combined with high fat consumption should normally lead to weight gain rather than weight loss.

Dr Er: “For most people weight gain is unpleasant but for people in recovery, who can gain several stones, this weight gain goes far beyond an aesthetic concern but involves both psychological and physiological problems. The stress caused by this conspicuous body change can also contribute to relapse.

“It is therefore important that we better understand the effects of cocaine on eating behaviour and body weight to best support drug users on their road to recovery.”

Additional reporting by PA