The intermittent fasting trend may pose risks to your heart

Intermittent fasting, a dietary approach where individuals restrict eating to specific time frames, has gained immense popularity recently. However, a new study unveiled at an American Heart Association meeting in Chicago suggests a need for caution. 

This study focused on a prevalent form of intermittent fasting where individuals consume all meals within an eight-hour window, leaving a minimum 16-hour daily fast, known as "time-restricted" eating, reports The Washington Post. 

Examining data from 20,000 adults in the US tracked from 2003 to 2018, researchers discovered concerning trends. Those strictly adhering to the eight-hour eating window faced a 91% higher risk of dying from heart disease compared to those following a traditional eating pattern spread over 12 to 16 hours daily.

Moreover, this elevated risk extended to individuals with pre-existing health conditions. 

Those with cardiovascular disease following the time-restricted eating pattern had a 66% higher risk of heart disease or stroke-related mortality. 

Similarly, cancer patients on this diet were more likely to succumb to the disease compared to those eating within a broader time frame of at least 16 hours a day.

The study's lead author, Victor Wenze Zhong from Shanghai Jiao Tong University School of Medicine, urges caution for individuals practising intermittent fasting, especially those with existing heart conditions or cancer. These findings underline the importance of careful consideration and possibly medical consultation before adopting such dietary practices for prolonged periods.

"Based on the evidence as of now, focusing on what people eat appears to be more important than focusing on the time when they eat," he added.

Zhong said that he and his colleagues conducted the new study because they wanted to see how eating in a narrow window each day would impact "hard endpoints" such as heart disease and mortality. He said that they were surprised by their findings.

"We had expected that long-term adoption of eight-hour time-restricted eating would be associated with a lower risk of cardiovascular death and even all-cause death," he said.

Losing lean muscle mass

The data did not provide a clear explanation for why time-restricted eating heightened health risks. However, researchers noted that individuals following a 16:8 time-restricted eating pattern, consuming meals within an eight-hour window and fasting for 16 hours, tended to have lower lean muscle mass compared to those eating throughout longer periods of the day. 

This finding correlates with a previous clinical trial published in JAMA Internal Medicine, which observed that participants assigned to a time-restricted diet for three months experienced more muscle loss compared to a control group not following intermittent fasting.

Preserving muscle mass as one ages holds significance, serving as a safeguard against falls, and disability, and bolstering metabolic health. Studies have underscored the link between low muscle mass and higher mortality rates, including an elevated risk of heart disease-related mortality, as highlighted by Zhong.

It's important to note that these findings do not establish causation. While the study identified a correlation between time-restricted eating and increased mortality, it couldn't determine cause and effect. Other habits or risk factors among individuals adhering to an eight-hour daily eating window might potentially explain their heightened likelihood of heart disease-related mortality. 

Additionally, the reliance on self-reported dietary information and the possibility of inaccurate reporting of eating durations by participants are acknowledged limitations of the study.