5:2 Intermittent Fasting Promising for Brain Health in Older Adults: Study

Intermittent fasting is one of the most popular methods for weight loss and metabolic fitness, and it may have even broader benefits.

Ekaterina Markelova/Shutterstock

A study published in Cell Metabolism in June suggests that 5:2 intermittent fasting could positively affect the brain health of older adults. The research shows that following an intermittent fasting regimen may improve cognitive function and overall brain health. The findings spark interest in exploring the potential benefits of fasting and brain function in older individuals.

Study Details

The study measured 5:2 intermittent fasting’s effects on important biomarkers in both men and women at risk of developing impaired cognitive function. For eight weeks, all participants maintained the U.S. Department of Agriculture (USDA) “healthy living diet,” consisting of fruits, vegetables, whole grains, lean proteins, low-fat dairy, and limits added sugars, saturated fats, and sodium.

Participants were divided into two groups, the “healthy living” group, which followed the USDA diet seven days per week, and the intermittent fasting group, which replaced all meals with two shakes totaling 480 calories on the two fasting days.

The participant pool consisted of 40 adults aged 55 or older who had insulin resistance and healthy cognitive function. The researchers’ rationale for the demographics was that “the prevalence of IR [insulin resistance] increases with age and obesity; thereby, older adults with overweight are at higher risk for accelerated brain aging and AD/ADRD [Alzheimer’s disease and related dementias].”

Both groups saw overall benefits in insulin resistance and a slowed pace of brain aging from their respective diet plans. However, the intermittent fasting group experienced improvement in memory and executive function at a rate of 20 percent more than the group following the healthy living diet alone. The intermittent fasting group also lost more weight. Neither group saw any change in biomarkers for Alzheimer’s disease.

5:2 Intermittent Fasting and Its Benefits

5:2 fasting is a version of intermittent fasting with normal dietary intake for five days a week and restricted caloric intake for two days. On restricted days, women usually reduce caloric intake to about 500 calories and men to about 600 calories. The diet was popularized by Michael Mosley, who authored “The Fast Diet” and was a British medical journalist.

What days to fast is up to you. James Hook, a chiropractor at Neurogan Health, told The Epoch Times in an email: “You can select which two days of the week you want to fast for, but ideally, this should not be consecutive. Otherwise, your energy levels will not be maintained.”

This staggered approach to eating is believed to offer health benefits such as weight loss, improved metabolic health, and reduced risk of certain chronic diseases. The calorie deficit created by the restricted days is touted as a safe and effective means for overall weight loss over time if you stick with the schedule and eat a normal, healthy diet on the off days.

“The main benefits are that your metabolism is significantly improved as a result of this,” Hook said.

A clinical trial published in 2020 in Clinical Nutrition found that a typical 5:2 intermittent fasting regimen is low-carb and high-protein and includes moderate fat intake. The trial found that on fasting days, the participants consumed more calories from protein than on non-fasting days and that overall caloric intake decreased after six weeks despite the inclusion of unrestricted days.

In June, a clinical trial published in JAMA Network Open found that 5:2 intermittent fasting was more effective for weight loss and showed better glycemic outcomes in Type 2 diabetics than the common pharmaceuticals ​​metformin or empagliflozin, making it a potential drug-free intervention option in early stages of the disease.

Potential Limitations of 5:2 Intermittent Fasting

The 5:2 fasting diet may not be a fit for everyone, as it can have certain limitations:

1. Not Sustainable for Some

One of the biggest hurdles with fasting is that many people find it challenging to stick to the restricted pattern of eating. Normal food consumption for five days and drastically reducing calories for two non-consecutive days each week can lead to inconsistency and make it challenging to maintain over the long term. Furthermore, people may be inclined to give up because of side effects such as hunger and fatigue.

Dan Gallagher, a registered dietitian with Aegle Nutrition, suggested a possible solution in an email to The Epoch Times.

“It’s important to keep hydrated properly, with both water and electrolytes, when you’re fasting,“ he wrote. ”This will help with hunger pains [and] will also help your energy levels remain higher, which will help you to refrain from breaking your fast.”

2. Potential for Overeating

On nonfasting days, there is a risk of overeating for some people who are seeking to compensate for the calorie restriction on fasting days. This pattern can negate the benefits reaped from the fasting days.

“People may not be used to fasting, and can try to balance out their calorie intake after these days by eating more than they normally would,” Hook said.

3. Lack of Nutrient Balance

Proper nutrient balance on fasting days when calorie intake is restricted may be challenging. If not carefully managed, this could lead to deficiencies in essential nutrients.

4. Potential for Developing Eating Disorders

Some individuals may develop an unhealthy relationship with food or an obsessive approach to fasting and counting calories or macronutrients, leading to disordered eating patterns.

5. Not Suitable for Everyone

Pregnant or breastfeeding women, people with a history of eating disorders, or those with certain medical conditions should consult a health care professional before attempting 5:2 fasting.

“I would advise that anyone who is vulnerable should not do this, particularly those with health concerns,” Hook said.

Aside from the possible limitations of 5:2 fasting to consider, the method shows promise for supporting brain health in older adults with the added benefit of weight loss. However, for weight loss alone, a clinical trial published in JAMA Internal Medicine in 2017 concluded that alternating fasting days does not lead to any more significant advantage in weight loss or weight maintenance than basic calorie restriction on a daily basis.