Cardiologists Tell Us What You Really Need to Know About Intermittent Fasting and Heart Health

For all of these reasons, Dr. Heffron ultimately says, rather definitively, that this is “not a noteworthy study.”

What research needs to be done to investigate this finding further?

Perhaps some of the above gaps in knowledge will be filled in when the full study is released. Still, even then, Dr. Heffron says a considerable amount of further work would be required to validate the results of this analysis. “You’d need to do the appropriate statistical analyses from the cohort that these data are derived from and then look for validation within other independent cohorts,” he says. “And if that pans out, then you would think about potential short-term-duration interventions, which are possible in nutrition.”

Generally speaking, Dr. Hunnes says a significant amount of additional research is needed on intermittent fasting beyond this analysis, especially regarding its impacts on heart health. “In fact, much more information in general is needed with regard to lifestyle and heart health,” she says.

She says this intel can be difficult to collect as there are limitations to nearly all nutrition studies. “There are so many variables and factors that are difficult to account for and are confounding,” she says. “If we were to conduct a long-term nutrition study where all variables could be accounted for—ie. 1,000 people live in a hotel or dormitory and are given access only to foods provided by the study, and were monitored in their daily activities 100 percent of the time, and all other variables are known—we could make grand conclusions.”

Dr. Heffron agrees. “The gold standard in health outcomes research is a randomized controlled trial, and it’s very difficult to randomize anybody to a nutritional intervention,” he says. “Modifying even one small aspect of a diet for a long-term study, which is what’s necessary to find out if someone dies or not as a result of that modification, is very difficult.”

TL;DR: What conclusions should we draw about the impacts of intermittent fasting on heart health? In the short term, we know that intermittent fasting can help people lose weight and reduce certain risk factors for heart disease. We don’t yet know how intermittent fasting affects human health in the long run.

If the data on intermittent fasting is inconclusive, what diets are shown to be beneficial to heart health?

Even though Dr. Heffron believes this abstract’s data should more or less be taken with a grain of salt, he says it’s okay to abandon intermittent fasting if you’re troubled by the new intel. In fact, he rarely recommends it per se anyway, despite the fact that there is evidence to suggest that intermittent fasting is an effective way to restrict overall calories and, in turn, mitigate major risk factors for heart disease. This is because he prefers to focus his counseling on encouraging behaviors patients will be able to maintain for decades, as those are better associated with improved heart health outcomes.

Such behaviors include better food choices, and Zumpano agrees that emphasis should be placed more on what you eat than when you eat it. “Focus on including heart-healthy foods and decreasing the things that we know can negatively impact your heart, like processed meats, processed foods, fast foods, junk foods, and sugary foods,” she says.