Is fasting the new anti-aging hack? For seniors, it's complicated

Think skipping meals is just for younger folks? Research suggests that when and how older adults eat can influence weight, heart health, and even cognitive function. There's a trade-off, though.

What happens when people over 60 swap three meals a day for a strict eating window? A new analysis of 31 studies finds surprising answers.

Intermittent fasting (IF)—cycling between periods of eating and fasting—has been lauded for its benefits for weight loss and improved metabolism in younger adults. But older bodies are different.

Published in the journal Nutrients, the research shows that moderate fasting plans helped seniors slim down and improve health, while extreme fasts backfired.

Slimming down without sacrificing strength

How much weight can a senior lose on IF? The headline: quite a bit! It seems that for older adults, moderate fasting plans can indeed help them slim down and improve their health. The review looked at different IF protocols, from time-restricted eating (TRE), where you eat only within a certain window each day, to the 5:2 method (two low-calorie days a week), and even Islamic Sunnah fasting (ISF).

When it came to shedding pounds, the researchers found some clear winners. They concluded that "TRE 16:8 and ISF showed the strongest comparative evidence for weight reduction in the RCT-based NMA, with acceptable short-term safety profiles in the included trials."

What that means is certain time-restricted eating protocols (eating within eight hours each day, fasting for 16 hours) and Islamic Sunnah fasting lead to the best weight loss in older adults who participated in studies that strictly tested how effective these methods are, and they appear safe for the short-term.

Even better, these moderate approaches often helped people lose weight without losing precious lean muscle mass, which is a huge win for seniors. Beyond the scale, the narrative synthesis of individual studies also pointed to clinically meaningful improvements in metabolic markers and blood pressure.

According to the researchers, "Intermittent fasting can improve heart risk factors and even boost memory in older people" in some cases. So, the potential benefits are definitely there.

Too much of a good thing: Hidden risks

But here's where the "catch" comes in. While moderate fasting looks promising, not all IF is created equal—and the strictest windows may be dangerous. The review stressed out the significance of an important warning, stating that "The cardiovascular mortality risk associated with very restrictive eating windows may emphasize the importance of moderate fasting approaches in this vulnerable population."

Put into simple words, "If you practice extreme fasting practices, and you're older than 60 years old, you might even increase the likelihood of cardiovascular mortality."

For example, extremely limited eating periods, like less than 10 hours, and extended fasting periods, exceeding 12.38 hours, were found to correlate with poor health outcomes such as reduced cognitive function scores and 58% greater cardiovascular mortality. It seems to serve as a significant warning that when it comes to fasting, especially for the elderly, moderation is not optional; it is necessary.

Planning a safe fast for later life

What does this imply for the elderly population? Firstly, moderation. According to the authors of this study, excessive fasting, both for more than 14 hours a day and for several days in a row, is not recommended for older individuals.

Secondly, any major changes in diet require consulting a physician, especially for those taking some medication or suffering from some illnesses. Thirdly, additional long-term studies are needed to understand the impact of different types of IF in patients aged over 60 who may have different levels of frailty and various illnesses.

The implications for the general public from the current research can be stated as follows: IF can serve as a non-medical way of achieving healthy aging and proper weight management, as well as improving mental health for senior citizens. Again, the key here is the moderate approach to IF.

As one of the authors says, fasting is "an evolutionarily conserved process," aimed at increasing strength. However, given today's lifestyle choices, people have the ability to disrupt their body's natural processes. For elderly people interested in IF, perhaps it would be wise to start slower, like a 10-hour daily feeding window, and see how their body responds.