Muscle Strength May Offer Greater Brain Health Benefits Than Ozempic

Muscle strength and brain health

Building stronger muscles could provide greater benefits for brain health than the current focus on weight-loss anti-obesity medicines such as Ozempic, researchers behind a recent study say.

In a retrospective analysis, scientists at Sichuan University in China found that grip strength and the placement of subcutaneous fat predicted neurodegenerative diseases and biological markers of brain ageing more effectively than broader measurements of muscle mass and total body fat.

"This study highlights the potential to lessen people's risk of developing these diseases by improving their body composition," explains Sichuan University epidemiologist Huan Song.

Physician Shishi Xu of Sichuan University led the research team, which examined nine years of data from 412,691 UK Biobank participants. Their average age at the beginning of the study was 56, and 8,224 later developed dementia, including Alzheimer's and Parkinson's diseases.

People who retained comparatively strong grip strength throughout the study were 26 percent less likely to develop a neurodegenerative condition such as dementia.

"Muscle quality, compared with muscle quantity, might play a more important role in the development of neurodegenerative diseases," the researchers write in their paper.

Subcutaneous fat distribution and neurodegenerative disease

The researchers also found that participants with a higher amount of arm fat relative to leg fat were 18 percent more likely to be diagnosed with a neurodegenerative condition.

That does not, of course, show that arm fat causes these neurodegenerative conditions. In addition, most participants were of Anglo-Saxon descent, meaning the results may not apply to other populations.

Even so, the way fat is distributed around the body may at least indicate health issues that could worsen brain ageing. For instance, many participants who later developed a neurodegenerative condition had previously experienced heart disease and strokes, both of which have been directly associated with excess fat.

Subcutaneous fat may indicate that fatty deposits are present in visceral organs - including the muscles - raising inflammation and reducing their function. This can then damage the inner linings of blood vessels, directly contributing to heart disease. Xu and colleagues suspect that this same lining dysfunction may also contribute to neurodegeneration.

Genes for fat-transporting proteins have likewise been linked with Alzheimer's disease, while animal research has implicated fatty diets and human studies have implicated western diets, which are well known for promoting unhealthy weight gain.

However, "the underlying mechanisms linking body composition and neurodegeneration have not been fully investigated," Xu and team explain.

Cardiovascular disease, belly fat and prevention

Furthermore, serious illnesses including stroke and heart disease can themselves make it much more difficult for patients to maintain muscle tone and manage changes in weight.

"This underscores the importance of managing these cardiovascular diseases right away to help prevent or delay the development of Alzheimer's, Parkinson's, or other degenerative diseases," says Song.

Belly fat was also linked to a higher risk of neurodegeneration. Among men with high levels of fat around the trunk, the disease rate was 3.38 cases per 1,000 person years, versus 1.83 cases in men with low levels of belly fat. For women with high abdominal fat levels, the neurodegenerative disease rate was 2.55 per 1,000 person years, compared with 1.39 among women with low amounts of belly fat.

"Targeted interventions to reduce trunk and arm fat while promoting healthy muscle development may be more effective for protection against these diseases than general weight control," suggests Song.

"These neurodegenerative diseases like Alzheimer's and Parkinson's affect over 60 million people worldwide, and that number is expected to grow as the population ages, so it's crucial that we identify ways to modify risk factors to develop some preventive tools."

This research was published in Neurology.