Muscle Loss Leads to Cognitive Decline
Muscle and strength are far more than just markers of physical prowess—they are life-and-death essentials, especially as we age. Research shows that low strength not only increases mortality risk and accelerates aging but may also be intimately connected to cognitive decline. Recent studies have shed light on this intriguing relationship, prompting us to ask: Does losing muscle in old age lead to diminished mental function, or might declining cognition contribute to muscle loss? A new study offers some compelling insights.
How the Study Worked
Researchers homed in on three traits known to wane with age:
Appendicular Lean Mass (ALM): The muscle tissue in the arms and legs, serving as a proxy for overall muscle mass.
Grip Strength
Walking Speed
They analyzed data from extensive genome-wide association studies (GWAS), chosen for two important reasons:
The studies provided objective data on body composition and functional abilities.
They enabled researchers to determine whether traits like low muscle mass and dementia shared a common genetic link or were independent of one another.
What the Study Found
The study revealed that ALM has a causal relationship with cognitive function, as well as with grip strength and walking speed. In essence, a person’s muscle mass can explain not only their physical capabilities—such as strength, balance, and mobility—but also aspects of their cognitive health, including memory, reasoning, and decision-making. Interestingly, while grip strength is an effective marker of overall strength, it does not directly predict cognitive function. When researchers explored the reverse—whether cognitive decline might lead to reduced muscle mass—they found that diminished cognitive function was indeed linked with lower ALM and slower walking speed, but again, not with grip strength.
To put it simply, an older individual diagnosed with sarcopenia (significant muscle loss) may experience declines not only in physical abilities but also in brainpower. Conversely, noticeable cognitive decline may lead to further loss of muscle and a slower pace in daily life. However, a strong grip may not necessarily indicate sharp cognitive function, nor will a weak grip always signal a loss of mental acuity. One telling sign is walking speed—slower than 3 mph could be a red flag for declines in both muscle mass and cognitive ability.
Nerd Knowledge
When muscle matters most
There’s an old soul song—famously sung by Otis Redding—that reminds us, “You don’t miss your water till your well runs dry.” Though the lyrics speak of lost love, they also serve as a metaphor for many of life’s essentials. In this case, think of muscle as the wellspring of both physical and cognitive vitality.
Consider that skeletal muscle constitutes roughly 40% of body weight and contains 50 to 75% of your body’s proteins. It even plays a critical role in regulating blood sugar by processing 80 to 85% of incoming glucose. In hospital settings, especially among older patients, muscle loss can be dramatic—losing as much as 2% of muscle mass per day, or over 15% in just one week. Factors such as immobility, the effects of medications, systemic inflammation, and even a calorie deficit contribute to this rapid decline, a condition known as ICU-acquired weakness (ICUAW). For someone already facing sarcopenia, ICUAW can be nothing short of devastating.
It’s a powerful reminder that it’s never too early to preserve muscle mass. Even modest resistance exercise can stimulate muscle protein synthesis, enhancing the benefits of high-quality protein in your diet. Combining strength training with proper nutrition not only boosts muscle growth but also curbs the breakdown of muscle tissue—a strategy that might one day be the difference between robust health and vulnerability during a health crisis.
Takeaways
1. Manage Inflammation for Better Health
Chronic inflammation is linked to various conditions, including obesity, type 2 diabetes, sarcopenia, and even dementia. Inflammation can break down muscle tissue and interfere with muscle repair, while prolonged inflammation in the brain may contribute to cognitive decline. Regular physical activity helps boost brain-derived neurotrophic factor (BDNF), a hormone crucial for long-term memory, and is associated with a lower risk of dementia.
2. Embrace an Anti-Inflammatory Diet
What you eat plays a vital role in managing inflammation. Aim to reduce or avoid foods that are fast, processed, refined, or deep-fried, as these can promote inflammation. Instead, focus on a diet rich in fruits, vegetables, legumes, and whole grains to provide essential vitamins, minerals, antioxidants, and fiber. Incorporating olive oil, nuts, seeds, and fatty fish such as salmon can also support overall health by supplying beneficial fats. Dark-colored produce, green and black tea, garlic, turmeric, and curry powder are excellent choices to help keep inflammation at bay. Pairing these nutritional habits with regular exercise can make a significant difference in maintaining both muscle mass and cognitive health.
Closing Thoughts
For years, I was caught in extremes—obsessing over my looks, the hours spent lifting, and the relentless pursuit of gym gains, while also spiraling into overthinking and letting negative thought patterns dominate my mind. I discovered that neglecting either the body or the mind only led to imbalance. It wasn’t until I learned to integrate mind and body work that my health truly took a leap forward. I aim to stimulate your mind with the latest science in my blogs and emails, but the real change happens when you act on what you learn. We live in a golden age of abundance, with tools and knowledge that previous generations could only dream of. It’s our responsibility to care for ourselves—so don’t let your body and mind waste away. Lift, get your protein in, and strive for balance every day.
Take care of yourself, no one else can do it for you.
— Michael Beiter
Personal Trainer
Nutrition, Sleep, Stress Management, and Recovery Coach
