Confirmed By Science: Low Muscle Mass And Excess Body Fat Can Negatively Influence Brain Health

Excess body fat and low muscle mass harm brain health, according to two studies, one published in 2019 and the other ongoing in 2025.

These studies provide insight into the most harmful types of adipose tissue and how the immune system's response to fat and muscle drives changes in cognitive function. Overall health, fitness, and cognitive function all contribute to preventing and reversing osteoporosis.

In this article, we'll examine both studies so you can draw lessons about how to keep your brain youthful, improve your “fluid intelligence”, and hone your ability to build stronger bones.

Fat, Muscle, and Fluid Intelligence

A 2019 study published in the journal Brain Behaviors and Immunity analyzed data from 4,431 late middle-aged, cognitively unimpaired British adults. The researchers sought to understand the cause of elevated immune system activity in the bloodstream of people with a higher body mass index (BMI). This heightened immune activity triggers immune activation in the brain, contributing to cognitive issues.¹

While BMI is easy to calculate using height and weight, it doesn't provide essential information about fat and muscle composition. This study used DXA imaging to measure participants' body composition, comparing lean muscle mass, visceral adipose mass, and non-visceral adipose mass.

Visceral adipose mass is fat tissue between and around organs in the torso, which makes it hard to observe externally. Non-visceral adipose mass is fat tissue that sits just beneath the skin, where it is typically easier to see on the body.

Researchers compared these detailed body composition measurements to fluid intelligence scores and bloodstream immune activation, assessed every two years over a six-year study period. Fluid intelligence is the ability to think and react to new situations in real time.

The study found that lean muscle mass and visceral adipose mass influenced fluid intelligence via immune activation. Non-visceral adipose tissue didn't significantly impact immune activation or intelligence.¹

Participants with higher levels of visceral fat and lower muscle mass had reduced cognitive function. For men, muscle mass and visceral fat were equally influential, whereas for women, muscle mass appeared to have a stronger impact on fluid intelligence.¹

The researchers suggest that these findings could help formulate diet and exercise protocols that increase muscle mass and reduce visceral adipose tissue to help preserve cognitive function in older adults.

Synopsis

Data on body composition, bloodstream immune activation, and fluid intelligence from more than four thousand older British adults showed that levels of muscle mass and visceral adipose tissue influence fluid intelligence. Higher muscle mass and lower visceral fat levels correlated with better cognitive function.

Results From Ongoing Study Confirm Muscle-Fat-Brain Link

At the annual meeting of the Radiological Society of North America, researchers presented new evidence that higher muscle mass combined with a lower visceral fat to muscle ratio correlated with a younger brain age.²

The ongoing study includes 1,164 healthy individuals who participated in whole-body MRI scans. Researchers used an algorithm to quantify their muscle volume, visceral fat, subcutaneous (non-visceral) fat, and brain age.

They estimated brain age using a computational model of chronological age based on a structural MRI scan of the brain. The program compared each scan to reference images from younger and older brains to estimate brain age.

The results showed that a lower ratio of visceral fat to muscle was associated with younger estimated brain age, while subcutaneous fat showed no significant relationship. In other words, more muscle and less visceral fat correlated with a more youthful brain.²

The researchers suggested that their system of brain and body scanning could be used to identify body composition goals for medical interventions to support optimal cognitive function.

Synopsis

Study results presented at the annual meeting of the Radiological Society of North America found that a lower visceral fat to muscle ratio was associated with a more youthful brain.

Building Muscle And Reducing Visceral Fat For Bone Health

The cognitive benefits of a high muscle-to-visceral fat ratio are significant for Savers.

Cognitive function supports independence and fluid intelligence– the ability to learn, adapt, and continue growing throughout your life.

A healthy brain also makes healthy lifestyle choices possible. Without strong cognitive function, making bone-healthy choices about diet, exercise, and lifestyle becomes difficult.

You need your critical thinking skills to assess new strategies and make the right choices. You also need fluid intelligence to implement behavioral changes based on new information. If the path you're currently on leads to bone loss, fractures, and reduced independence, fluid intelligence helps you change course.

Increasing muscle mass benefits your brain.^1,2 Muscle mass also drives bone formation. When you exercise or perform any physical activity, your muscles apply force to bone. That force, per Wolff’s Law, stimulates new bone formation.

The same muscle growth that helps ensure a healthy brain also improves the health of your bones. This dual action exemplifies the benefits of a holistic approach to preventing and reversing osteoporosis– every step you take creates a ripple of positive effects.

Synopsis

A healthy brain facilitates a bone-healthy lifestyle and the fluid intelligence that allows you to adopt new bone-building behaviors. Increasing muscle mass benefits your brain and also your bones, because muscle applies the force that stimulates bone growth.

What This Means To You

Practice regular exercise to build muscle, support a more youthful brain, and strengthen your bones.

The recommendations of the Osteoporosis Reversal Program can help you do just that. The ORP is based on scientific research to formulate a bone-building protocol that touches every part of your life. This holistic approach gives you many paths to the future you want.

Start with small changes that help you build muscle or improve your diet; as you incorporate them into your routine, you'll find it easier to add more. Before you know it, you'll start seeing the bone-health results you need to prevent fractures while maintaining an active, joyful life.

References

¹ https://www.sciencedirect.com/science/article/abs/pii/S0889159119306531

² https://www.rsna.org/media/press/2025/2614