Losing kilos but gaining stress

SIGNING up to the latest calorie-­cutting diet might seem a surefire way to drop a few kilos and boost your self-esteem.

But new research suggests the opposite: dieting is so stressful it might do more harm than good.

US scientists found that dieters lost an average of 0.9 kg over three weeks but reported feeling significantly more stressed than their non-dieting counterparts.

Moreover, they actually had measurably greater amounts of the stress hormone cortisol in their saliva, with levels higher after three weeks than before starting the diet.

“Dieting may be deleterious to psychological wellbeing and biological functioning,” the authors said.

“Changes in clinical recommendations may be in order.”

The study comprised 121 women who were randomised to four groups. 

One group monitored their calorie intake and restricted it to 1200 kcal per day. Another monitored their intake but ate what they liked, while the third group was given 1200 kcal per day but did not keep track of what they were eating. The fourth, the control group, ate normally.

Women restricting their calories lost an average of 0.9 kg in three weeks, while non-dieters gained 1.1 kg.

The researchers noted however that cortisol serves a range of functions and more research was needed to understand the relationship to dieting.

Psychosom Med 2010;72:357-64