A surprising conclusion from a study presented at a medical convention cast doubt on the safety of intermittent fasting, a popular approach for losing weight by limiting meal consumption to specific periods.
According to the study, limiting mealtimes or intermittent fasting to only eight hours per day increases the chance of mortality from heart disease by 91%. The American Heart Association merely published an abstract, leaving scientists to speculate on the study protocol’s contents. According to the AHA, other experts examined the paper before it was released.
Lifestyle approaches for weight loss have come under fire as a new generation of medications helps patients lose weight. Several doctors questioned the study’s findings, saying they could have been skewed by differences – such as underlying heart health – between the fasting patients and the comparison group, whose members consumed food over a daily period of 12 to 16 hours.
“Time-restricted eating is popular as a means of reducing calorie intake,” Keith Frayn, emeritus professor of human metabolism at the University of Oxford, said in a statement to the UK Science Media Center. “This work is very important in showing that we need long-term studies on the effects of this practice. But this abstract leaves many questions unanswered.”
Shanghai researchers analyze Health Survey Data from 20,000 adults
The researchers, led by Victor Zhong of Shanghai Jiao Tong University School of Medicine, examined data from over 20,000 adults who participated in the US Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey.
The study analyzed questionnaire responses and death data from 2003 to 2019. Scientists warned that there was a chance for mistakes because it was based in part on forms that challenged patients to recollect what they ate over two days. Approximately half of the patients were men, with a mean age of 48.
According to Zhong, the researchers believed the patients continued intermittent fasting for an unknown period.
Fasting patients were more likely to be younger men with a greater BMI and food insecurity, he noted by email. They also had decreased rates of hypertension, diabetes, and cardiovascular disease, according to self-reports. “We controlled for all these variables in the analysis, but the positive association between 8-h time-restricted eating and cardiovascular mortality remained,” Zhong told me.
The abstract was given at the AHA’s Lifestyle Scientific Sessions in Chicago. 3