A Huge New Study Found That a Popular Diet Is Linked With a 91% Higher Risk of Cardiovascular Death—Here's What Cardiologists Say
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A popular diet habit has been linked with a 91% higher risk of death from heart disease—but that statistic may not necessarily be as dire as it seems.
The American Heart Association reported that a study of over 20,000 adults (average age 49, 73% of which were white) indicated that participants who restricted their eating schedule to eight hours per day (a popular form of intermittent fasting) showed a 91% higher risk of death from cardiovascular disease.
The study followed participants for a median of eight years and a maximum of 17 years.
People in the study with existing heart disease who restricted their eating to eight to 10 hours per day showed a 66% higher risk of death from stroke or cardiovascular disease. Participants with heart disease or cancer also showed an increased risk of cardiovascular death, which, if we're being honest, is sort of a given when you compare them to anyone without those conditions.
Related: What to Know About 16:8 Intermittent Fasting
The study also found that participants with cancer and an eating duration of 16 hours or more daily showed a lower risk of cancer death.
Further, the study claimed that time-restricted eating didn't appear to reduce death risk in general from any or all causes, and when compared with an unrestricted eating schedule, didn't appear to improve longevity substantially.
“Overall, this study suggests that time-restricted eating may have short-term benefits but long-term adverse effects," Christopher D. Gardner, Ph.D., FAHA, the Rehnborg Farquhar Professor of Medicine at Stanford University, told the AHA. "When the study is presented in its entirety, it will be interesting and helpful to learn more of the details of the analysis."
Now, what does all of that mean for the average person?
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It's actually unclear, Dr. Cheng-Han Chen, MD, board-certified interventional cardiologist and medical director of the Structural Heart Program at MemorialCare Saddleback Medical Center in Laguna Hills, Calif., says.
"This retrospective study found an association between self-reported time-restricted eating duration of less than eight hours and a high risk of cardiovascular mortality. As with all observational studies, the direction of causality cannot be determined," he explains. "Also, without the full study data being published, the relative sizes of each time-restricted eating group studied (those eating less than eight hours, those eating for eight to 10 hours, etc.) are not known, nor are the baseline demographics and co-morbidities of each time-restricted eating group."
Read: We don't know enough about the individual participants in the study or their personal health histories to draw any serious conclusions about the potential risks of intermittent fasting just yet.
Related: The Best Proven Ways to Prevent Heart Disease
Dr. Chen notes that differences in the baseline demographics of the study participants, plus potential bias (and potential inaccuracies) in participants' recall of their eating patterns can also skew the data.
Further, he says, "These findings run counter to many previous studies which find benefits of time-restricted eating to cardiovascular and metabolic health. The full study has not yet been published, but there may be differences in the baseline characteristics of the time-restricted eating groups that could account for these surprising findings."
All that to say: Should you quit intermittent fasting?
According to Dr. Chen, if intermittent fasting or time-restricted eating works well for you and your physician is happy with your results and overall health, you can safely stick to the habit: "I would still recommend intermittent fasting for my patients as a way to lose weight, improve blood sugar control, improve cholesterol and for overall cardiovascular health."
Next, Are You Still Doing Time-Restricted Eating or Want to Try It? The Best Tips for Intermittent Fasting
