The enigma of sudden cardiac death related to dieting.

The use of liquid protein products for treatment of obesity in the United States in the 1960s and '70s was associated with an increased risk of sudden cardiac death. The latter was related to long QT interval occurring in the absence of structural abnormalities of the heart. In an attempt to increase understanding of this phenomenon, the authors examined the possible role of diet-related circumstances. No evidence of increased incidence of sudden cardiac death or significant lengthening of QT interval in obesity, weight loss, starvation and dieting by methods other than liquid protein intake were found. It was concluded that sudden cardiac death during use of liquid protein products remains an enigma, but that other methods of properly medically supervised dieting appear to be safe.