Men who yo-yo diet are not increasing their risk of dying, according to researchers at the Royal Free and University College in London, England.

Previous research has suggested that weight fluctuation can increase the risk of dying from cardiovascular disease and other conditions.

Researchers conducted a study to look at the relationship between weight change and weight fluctuation and death rates in 5,608 middle-aged men, ages 40 to 59. Changes in weight observed during a 12 to 14-year period were related to mortality during the subsequent 8 years.

There were 943 deaths from all causes: 458 cardiovascular disease and 485 non-cardiovascular disease deaths. Those with stable weight or weight gain had the lowest total cardiovascular disease and non-cardiovascular disease deaths.

Sustained weight loss or weight fluctuation (loss-gain or gain-loss) showed a significantly higher rate mortality risk than stable weight even after adjustment for lifestyle variables. Adjustment or exclusion of men with preexisting disease markedly reduced the increased risk of cardiovascular disease and total mortality associated with sustained weight loss and weight gain-weight loss.

In long-term nonsmokers, any weight loss since the start of the study was linked with an increased risk of mortality, but this was markedly decreased by adjustment for preexisting disease. Recent ex-smokers showed the most marked increase in mortality associated with sustained weight loss, according to the study published in the Archives of Internal Medicine.

"The increased mortality in middle-aged men with sustained weight loss and weight fluctuation is determined to a major extent by disadvantageous lifestyle factors and preexisting disease," concluded the researchers. "The evidence suggests that weight loss and weight fluctuation in these men does not directly increase the risk of death."

Other sources: Annals of Internal Medicine