Intermittent Fasting Raises Heart Death Risk by 91%.

In 2024, researchers from Shanghai Jiao Tong University analyzed data from over 20,000 U.S. adults (average age 49) in the NHANES survey from 2003-2018, followed until 2019. They compared those eating in an 8-hour window (a common IF method) to those eating over 12-16 hours, adjusting for age, diet, and health factors.

The 8-hour eaters had a 91% higher risk of cardiovascular death and, for those with heart disease, a 66% higher risk of dying from heart issues or strokes. IF didn't lower overall death risk, and eating over 16 hours cut cancer death risk in cancer patients.

A 2023 study found IF increases disordered eating risks, like bingeing or restricting, by 20-30% in some groups. Another from 2023 reported side effects like headaches (61%), lethargy (68%), and mood swings (58%) in adults trying IF.

Talk to your doctor before trying intermittent fasting, especially if you have heart issues.