'Skinny Fat' Types Have Higher Dementia Risk

Sarcopenic obesity, or more commonly, 'skinny fat', is a condition that's more common than you'd think. This is where a slim look can hide the fact that the upper arms, upper legs, and, in particular, the tummy area all have a high percentage of fat, while the body has low muscle mass and strength. 

 Sarcopenic obesity is uncommon before 60 but tends to develop beyond this age. It’s no secret that most of us in the older age category don’t have much muscle tone and often have a bulge in the middle, even if we look thin and we’re the envy of our friends who are struggling with serious weight problems. But the skinny-fat people are not in such great shape (literally). One of the problems is an increased risk of dementia. 

Higher Levels of Inflammation

Sarcopenia -- the loss of muscle mass and strength -- is a normal feature of aging, but it’s not a good one. A number of health disorders are associated with it -- more so if it takes place in conjunction with too much visceral fat, the kind stored around abdominal organs. The combination of sarcopenia with belly fat creates higher levels of inflammation in the body and eventually impairs functional abilities. Mobility is diminished; walking speed is reduced; it's harder to climb stairs; the risk of knee osteoarthritis, falls, type 2 obesity and even depression all rise. Only one study has looked at the association between sarcopenic obesity and cognitive functioning. The researchers found that among the 1,127 Americans over 70 included in the study, those with sarcopenia, obesity or both had worse cognitive functioning than those who had neither.

Losing Your Ability to Think

Researchers from Florida Atlantic University wanted to take a closer look at the brain-health connection, and see if the findings of this 2012 study could be confirmed. So they recruited 353 men and women with an average age of 69 who had either sarcopenia alone, obesity alone, or both, i.e. sarcopenic obesity/skinny-fat syndrome. The volunteers were given a range of cognitive tests, functional assessments (such as grip strength and ability to get up from a sitting position), and body composition measurements (e.g. body mass index, body fat percentage and muscle mass). The researchers found the 'skinny fat' participants performed consistently worse on cognitive tests compared to the other two groups. They had lower executive function – the ability to plan, organize, pay attention and manage time. They also performed worse on tests of working (short-term) memory, mental flexibility, time and space orientation, and the ability to control emotions and desires. All of these cognitive deficits are also found in those with dementia. The research team believes the explanation for these findings resides in a number of inter-related mechanisms, such as lack of exercise, low grade chronic inflammation, free radical damage and insulin resistance. It’s worth noting that the earlier study also suggested inflammation and insulin resistance as factors.

Prevent and Reverse Sarcopenic Obesity

With aging, members of both genders see their hormones go down. Women's estrogen levels fall. This prevents muscle growth and leads to redistribution of fat – mainly to the visceral areas – the gut area. In men, testosterone drops, leading to the central distribution of fat and loss of lean mass. In sarcopenic obesity, fat gets deposited in muscles, leading to toxicity, damaged muscle cells, and degradation. 

 Even so, much can be done to mitigate these and other nasty effects of aging. Lead author of the latest trial, James Galvin, Professor of Integrated Medical Science and Associate Dean for Clinical Research, said that 'skinny fat' types should be targeted with strength training and weight management to prevent cognitive decline in later life. Practicing geriatrician and clinical researcher John A. Batsis, M.D., agrees but also adds aerobic exercise. He said resistance and aerobic exercise counteract age-related inflammation, improve insulin sensitivity, prevent fat buildup in muscles, and help maintain skeletal muscle strength and function. While no specific type of diet has been tested in older adults with sarcopenic obesity, Dr. Batsis recommends a Mediterranean-style diet or the DASH (Dietary Approaches to Stop Hypertension) eating plan, together with a higher protein intake – half a gram of protein per pound of body-weight, eaten throughout the day, not all at once. This should support healthy muscle aging.

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1. https://www.ncbi.nlm.nih.gov/pubmed/22611388
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5995418
3. https://www.newsweek.com/skinny-fat-body-type-linked-dementia-risk-study-1008785