An initial analysis of a long-term study into the effects of “intermittent fasting” was recently presented at a conference of the American Heart Association. Fasting 16 hours daily appears to be associated with a higher risk of dying from cardiovascular disease, compared to fasting 8-12 hours.
Observational study
The study followed more than 20,000 American adults with an average age of 49 for approximately 8 years. At two points during this period, participants reported what they had eaten over the past 24 hours. They also recorded their first and last eating moments of a day for the study. The researchers used this to calculate how long the participants fasted per day. It was then examined whether there were any links between the participants’ fasting period and their risk of mortality.
Increased risk of mortality from cardiovascular disease
During the course of the study, 2,797 participants died, of which 840 from cardiovascular disease and 643 from cancer. A fasting period of at least 16 hours was found to be associated with a more than 90 percent increased risk of dying from cardiovascular disease. This was compared to a fast of 8-12 hours per day. According to the researchers, that is the American average for adults. For the total group of participants, no significant associations were found between the duration of fasting and total mortality or cancer mortality.
Heart Foundation
The Dutch Heart Foundation takes this analysis seriously but emphasizes that no causal relationship has been established. This is an observational study, not an intervention study. It is also unclear whether the quality of the diet was included in the study. Also, nothing is known about the profile of people who fast intermittently, such as body weight, lifestyle and other factors that increase the risk of cardiovascular disease. The Heart Foundation is waiting for the final publication for more clarity. In addition, more research is needed to draw conclusions about the effects of intermittent fasting on heart health.
Sources: Heart Foundation and American Heart Association
