If you’ve read about dieting recently, chances are you’ve come across claims that intermittent fasting ― where participants stop eating for set periods of time ― can damage your heart health.
A new study has found that those who partake in the diet, specifically those who eat during an eight-hour window, face a whopping 91% higher chance of facing heart disease than those who don’t.
But is it true?
Well, let’s ask the study author
Senior study author Victor Wenze Zhong, chair of the Department of Epidemiology and Biostatistics at the Shanghai Jiao Tong University School of Medicine in Shanghai, stated himself that the results of the preliminary study were not conclusive.
“Although the study identified an association between an eight-hour eating window and cardiovascular death, this does not mean that time-restricted eating caused cardiovascular death,” Dr. Zhong said.
In fact, the study has not been peer-reviewed or published in an academic journal yet.
And though study authors have added a poster presentation of their research abstract since launching the press release on which many articles were based, it’s still only available as a press release.
Then there’s the fact that the study is based on observational research ― in this case, their data on participants’ diets started from surveys (via the National Health and Nutrition Examination Survey) in which participants self-reported their food intake.
This is a pretty unreliable method, which the press release confirmed ― “The study’s limitations included its reliance on self-reported dietary information, which may be affected by participant’s memory or recall and may not accurately assess typical eating patterns,” it reads.
The study didn’t take external factors into full account, either
The authors of the study linked the self-reported dietary data from 2003-2018 to a database of deaths from 2003-2019, both of which are administered by the Centres for Disease Control and Prevention.
Handy as that is, it doesn’t take into account external factors that might be making the intermittent fasters less well than those who don’t do the diet.
“Factors that may also play a role in health, outside of daily duration of eating and cause of death, were not included in the analysis,” the press release admitted.
Dr Pam Taub, a cardiologist at UC San Diego Health, told NBC News, “It’s a retrospective study looking at two days’ worth of data, and drawing some very big conclusions from a very limited snapshot into a person’s lifestyle habits.“
That’s not to say that the results might never be true ― but, until a gold-standard blinded randomised controlled trial produces the same results, it might be a good idea to do whatever works best for your health diet-wise.