Sarcopenia

 

There is an “Obesity paradox” among older Americans. This describes the unexpected finding that slightly overweight older people with a particular disease have better outcomes than their normal-weight or underweight peers.  Overweight is measured by a formula called the Body Mass Index (BMI), which measures height, weight, and age. A recent review in 2023 by Moustapha Dramé confirmed this observation that being a little overweight for older adults is beneficial. Even though obese people are more vulnerable to diseases, including an increased risk of infections, cancer, and heart disease. However, once you get a disease, having greater functional reserves might come in use. But there is a more interesting story to tell rather than simply weight.

BMI is not a good way to measure healthy body weight, especially for older adults. Once you reach 30 years of age, muscle begins to reduce. By the time we reach 70, we may have only half the muscle we had in our 20s. This is not only a function of age but a function of poor nutrition, inactivity, and a general difficulty in building muscle. Women’s menopause might also make things worse. Physicians call this Sarcopenia, the common tendency to lose muscle mass due to aging, but it does not have to be like this.

Loss of muscle mass is a serious threat to health.  It contributes to disability and frailty. In addition, studies show that there may be an association between sarcopenia and rheumatoid arthritis, falls, and even dementia. Building muscle in older age is difficult but possible. A person can only build muscle through resistance training, not just walking. We can use our own body weight (e.g., by doing push-ups and squats) and lifting household items such as soup cans. One of the few areas that is easy to change is diet. Older adults don't eat enough protein.

Rei Otsuka and his colleagues have shown that greater protein intake improved muscle mass for men but not for women, again might have to do with menopause and the role of estrogen (especially estradiol). Women have it worse, since the loss of estradiol increases fat, decreases bone density, as well as muscle mass and muscle strength. All of these factors significantly contribute to the development of a condition termed “sarcopenic obesity.” It is that much harder for women to retain their muscles. But diet and exercise still seem to help, and increasing protein intake seems to help.

Keisuke Sakurai and his team compared a high-carbohydrate (HC) diet mainly composed of cereal against a protein-balanced (PB) diet with high intake of legumes, vegetables, seafood, meat, and eggs. Cognitive function was significantly higher in the PB group than in the HC group in a Japanese group.

Addressing sarcopenia might also prevent falling. Improving balance and flexibility by strengthening core muscles (chest, back, belly, hips, glutes, and thighs) and careful stretching can help prevent falls, a major cause of disability and death. Avoiding falls can be as simple as wearing stable shoes and having well-lit paths, to maintaining strength and flexibility. However active you are, don’t use ladders and perform other risky actions.

What is good for muscles is also good for the brain. A healthy body means a balanced diet and staying as active as you can.

I shrunk

 

I went to get my annual physical check-up, and I came out 6 centimeters shorter than I thought I was going in. From 188 cm to 182cc! I might lose another 6 centimeters if I am lucky enough to continue to age. It’s mainly in my torso, as what has shrunk is the soft tissue in between my vertebrae in my spine. There are 33 of them, all stacked one on top of the other. In humans, the 24 upper vertebrae are separated by discs that allow movement, while the 9 lower vertebrae are fused. Usually, these discs shrink because of osteoporosis, but in my case, it is pure aging. The discs lose some of their moisture and shrink as we age. We become drier. A human embryo is about 90 percent water, a newborn child about 80 percent, a mature adult about 70 percent, and an older adult about 60 percent water, while those between 70-80 years of age are only 50 percent water. I wonder what water percentage a 100-year-old would have.

Driving home from the clinic, as I was thinking how lucky I am to be able to enjoy aging, despite shrinking, I remembered the Aristotelian view of aging. I use this example with my students. Aristotle defined aging as a natural, inevitable process of becoming cold and dry, characterizing it as a "natural disease" and the gradual extinction of innate heat. He believed life requires warmth and moisture, but over time, the body’s "innate heat" diminishes due to the consumption of "radical moisture" or fuel. If you believe that you get old because you are drying out and losing heat, then the therapy that would reverse this is a sauna. Which is why hot baths were so popular in the gymnasiums during Roman times. They believed that this method of moisturizing rejuvenated the lost moisture and heat.

Romans followed a ritualized sequence: beginning in the tepidarium (warm room), moving to the caldarium (hot, steamy room), using the laconicum (hottest dry room), and finishing in the frigidarium (cold plunge). Recent studies have supported these beliefs. In a 2017 study on a Finnish male population, Tanjaniina Laukkanen and his colleagues reported that moderate to high frequency of sauna bathing was associated with lowered risks of dementia and Alzheimer's disease. In a review, the same researcher reported that saunas are linked to several health benefits. These include a reduction in the risk of heart diseases such as high blood pressure, cardiovascular disease, and pulmonary diseases, as well as less arthritis, headache, and flu. Maybe Aristotle was onto something when he identified water as the giver of life. But as we get older, we do not feel as thirsty as we did when younger and therefore drink less. This results in less water around our cells and points to an increased risk for dehydration.

Japanese culture is also centered around the bath, more so than just cleanliness. So, we expect to see this advantage reflected in life expectancy. Finnish life expectancy at around 81-82 is less than Japan’s 84-85. Although moisture might be a contributing factor to long life, there are other things that promote long life. While we all ponder this, remember that we are still shrinking, and although some might also experience reduced spinal mobility because of this dryness, it does not have to restrict mobility. There are things we can do to remain active, stay hydrated, and enjoy our shrinking lives.

Stay Hungry

 

We all know that we must not overeat. It’s always good to remain a little hungry. The Japanese saying that means "remain a little hungry" or eating until you are 80% full is hara hachi bu (腹八分目).   In the United States we do not have that saying. What we do have is an obesity problem with older adults in the US.

Obesity rates among older Americans have climbed significantly over recent decades, doubling from roughly 22% in the early 1990s to around 40% today. This is nearly twice the rate of Japan. Obesity is rising, with a third of Japanese men (32%) and a quarter (24%) of Japanese women aged 60 and older being obese. In most cases, the body works better with fewer calories.

Staying a little hungry is good for the body. Caloric restriction can work both by eating fewer calories per day or by fasting for 10 hours a day. Fasting might be the easiest way to achieve this by eating mid-afternoon, giving your body five hours to digest before going to sleep. Then overnight, this is where the magic happens, when the body recycles fat and other dead cells for energy.  This has been shown to result in lower body weight and less body fat, improved insulin sensitivity, lower blood pressure, and reduced inflammation. There are some problems, however.

Some medications must be taken with food, making it difficult to fast. It also means that you have to be more careful to ensure that you have a balanced diet that includes protein to reduce muscle loss and essential minerals to maintain healthy nerves. Women gain less from fasting than men, as sometimes fasting raises stress hormone levels, causing fatigue or sleep issues. In general, eating fewer calories is beneficial for the body.