Multiple studies have found that having greater muscle mass is associated with longer lifespan and lower mortality risk. For example, a large cohort of older adults showed that all-cause mortality was significantly lower in those with the highest muscle mass compared to those with the least. In fact, “the greater your muscle mass, the lower your risk of death,” as one researcher summarized.

This adds to evidence that body composition is a better predictor of mortality than BMI in older individuals.

A 2023 meta-analysis of 16 prospective cohort studies further confirmed that low skeletal muscle mass is strongly linked to higher risk of all-cause mortality.

In other words, maintaining muscle mass appears to be protective for longevity, whereas sarcopenia (low muscle mass) is associated with increased mortality.

Because women start with less muscle and experience menopause-related hormonal changes, they can be especially vulnerable to age-related muscle loss.

While both sexes undergo age-related muscle atrophy, women tend to remain at a lower overall muscle mass in later years, potentially increasing their susceptibility to sarcopenia and its consequences.

Frailty and functional decline: Diminished muscle mass is a major contributor to frailty in the elderly, manifesting as weakness, slower mobility, and increased risk of falls and fractures. Sarcopenia is in fact “a major factor in increased frailty, falls and fractures,” often leading to loss of independence.

Older adults with very low muscle mass have more difficulty performing daily activities and a lower overall quality of life. They may require assistance with basic tasks, and are more likely to suffer fall-related injuries.

This frailty cascade can result in greater need for hospitalization or long-term care.

Lack of muscle is also linked to metabolic decline and insulin resistance. Skeletal muscle is a key site for glucose uptake; when muscle mass is low, the body’s metabolic efficiency drops.

Research shows that lower muscle mass is associated with greater insulin resistance, which can predispose individuals to type 2 diabetes and other metabolic disorders.

Sarcopenic individuals often have higher levels of blood sugar and difficulty regulating insulin.

Additionally, low muscle mass correlates with worse overall health outcomes – including higher rates of infection, slower recovery from illness, and poorer health-related quality of life.

If muscle loss progresses unchecked, it can initiate a vicious cycle of further inactivity, disability, and health deterioration, ultimately even increasing mortality risk.

In summary, inadequate muscle reserve negatively affects strength, immunity, metabolic control, and day-to-day well-being, underscoring the importance of preserving muscle as we age.

The drop in estrogen during menopause is associated with accelerated loss of muscle mass and strength, which “can accelerate sarcopenia” in women.

In other words, postmenopausal women often face a heightened risk of muscle decline.

Association between muscle mass and insulin sensitivity independent of detrimental adipose depots in young adults with overweight/obesity.

With aging, the muscles become less responsive to smaller protein doses (a phenomenon known as “anabolic resistance”), so older adults need higher protein intakes to maintain muscle and function.

Notably, inadequate protein or overall malnutrition is recognized as a key risk factor for accelerated muscle loss – without enough dietary protein, the body cannot rebuild the muscle tissue that is continually broken down, hastening sarcopenia.

Conversely, ensuring sufficient protein (along with resistance exercise) markedly helps in preserving and building muscle in older adults.

Resistance training and protein are synergistic: protein intake and exercise are the main non-pharmacologic drivers of muscle anabolism, stimulating muscle growth and slowing atrophy.

Studies show that higher protein diets can improve muscle outcomes in aging. For example, a 2022 systematic review found that in adults over 65, consuming around 1.2–1.5 g of protein per kg daily led to significant gains in lean body mass when combined with exercise, compared to lower protein intake.

Protein supplementation in trials has also modestly increased strength during resistance training programs.

These findings reinforce that adequate dietary protein is crucial for muscle maintenance: it provides the necessary building blocks to repair muscle fibers and counteracts age-related muscle breakdown.

Health organizations uniformly emphasize a balanced, protein-rich diet (along with regular exercise) as a cornerstone of preventing sarcopenia and supporting healthy aging.

In summary, older individuals should prioritize protein intake to help preserve their muscle mass, strength, and metabolic health as they age, thereby improving longevity and quality of life.

Sarcopenia (age-related muscle loss) is influenced by factors such as physical inactivity, obesity, chronic illness, hormonal changes, and even insulin resistance.

Without intervention, this loss of muscle mass and strength leads to greater frailty and metabolic problems in older adults.

Maintaining muscle through exercise and proper nutrition can help slow these declines.

Men have significantly more skeletal muscle both in absolute terms and relative to body weight – one MRI study found men average about 33 kg of skeletal muscle (~38% of body weight) versus ~21 kg in women (~31% of body weight).

This sex difference arises largely from hormonal and developmental factors (e.g. higher testosterone in males) and persists into older age.

Expert panels recommend that healthy seniors consume at least about 1.0–1.2 grams of protein per kilogram of body weight per day – higher than the 0.8 g/kg minimum for younger adults – in order to preserve lean mass and strength.

The international PROT-AGE study group, for instance, advises ≥1.0–1.2 g/kg/day for adults over 65, with even greater intake (1.2–1.5 g/kg) for those who are ill or very active.