I’ve been talking about sarcopenia, also known as age-related muscle loss. Sarcopenia brings to mind a shrinking frame. But that’s not always the case. Sometimes, in the case of sarcopenic obesity, body size and even weight can stay constant (so BMI is a poor indicator). They can even go up (or, of course, down). What’s happening is a trade-off, muscle-for-fat:
With sacopenic obesity, it may appear that muscle loss is not present or is not progressing. It can be “invisible” thus fail to be a cue for you to act. And not acting is dangerous because:
- Obesity increases inflammation which in turn increases muscle loss. And muscle loss can increase obesity. As the article below states, they potentiate each other.
- When muscle loss is not apparent, there is greater risk for falls and other injuries. You go to use a muscle and are surprised when it isn’t there.
- You may die sooner. “A recent meta-analysis demonstrated that sarcopenic obesity is associated with a 24% increase in the risk of all-cause mortality compared to patients without sarcopenic obesity, particularly in men.”
Sarcopenia And Sarcopenic Obesity, Korean Journal of Internal Medicine, November 2016
Recently, the new concept of sarcopenic obesity has emerged, reflecting a combination of sarcopenia and obesity. The rapidly increasing prevalence and serious consequences of sarcopenic obesity are recognized as a critical public health risk in the aging society. Sarcopenia and obesity share several pathophysiological mechanisms, and they may potentiate each other.
It’s not only older people who are affected. Muscle loss can begin by age 30.
There are significant differences among individuals in peak muscle mass, the age at which muscle loss begins, and the amount of muscle that is lost over time
- Insulin resistance plays an important role in muscle fiber atrophy and mitochondrial dysfunction. … In the KSOS study, type 2 diabetes was independently associated with an increased risk of sarcopenia.
- Hormonal changes, e.g. reduced androgen and estrogen concentrations decrease muscle mass and strength.
- Previous studies have suggested that sarcopenia is an inflammatory state that is driven by proinflammatory cytokines and oxidative stress.
In the diagram below, the red boxes on the top represent inputs or “causes” if you will of sarcopenic obesity. The boxes at the bottom represent outputs, conditions or diseases to which sarcopenic obesity contributes.
A vicious cycle may exist between the accumulation of ectopic fat and the loss of skeletal muscle mass since they have a reciprocal influence on each other.
Probably everyone will experience some degree of sarcopenia or sarcopenic obeisty in their lifetime. It can begin as early as age 30 and progress. I’ve been outlining actions you can take to reduce it, such as:
- Exercising (although exercise alone will not stop muscle loss).
- Getting enough protein but, just as important, not getting too much, especially too much sulfur-containing animal protein. Eat beans.
- Reducing fat intake since dietary fat, especially saturated fat found primarily in animal foods, has been shown to increase insulin resistance.
- Consuming enough calories and enough nutrients (this becomes more difficult with age).
- Maintaining a state of low-level metabolic alkalosis (by eating lots of potassium-containing fruits and vegetables and by not eating much animal food).