I don't perform scientific research. I only comment upon the results in this column.

But I am pleased to announce a positive trend in the type of research I've been reading about recently. So many of the studies now consider a concept crucial in philosophy.

Interdependence.

Unlike independence, interdependence acknowledges that acts do not occur in a vacuum. That all acts in some way affect other things even some previously seen as opposite or unrelated.

The body and the mind, for instance, were viewed as independent for too long in the Western world. Now the Western world has accepted the Far East notion of both being interdependent and research looks for ways that the one affects the other.

A study done last year at the University of Edinburg, for instance, showed that exercise later in life does more to keep the brain functioning optimally than brain-based activities such as solving crossword puzzles and social engagement.

Over a three-year period, researchers took brain scans of nearly 700 subjects over the age of 70. They also questioned them on their exercise habits.

Those who reported regular exercise showed less brain shrinkage at the end of the three years than those who did little exercise. Scientists know that problems with cognition and memory, such as forgetting where you placed your keys, increase with brain shrinkage.

The research also showed that those who exercise have less damage in the brain's white matter the area responsible for transmitting messages from one part of the brain to the other than those who did little exercise.

Professor James Goodwin, Head of Research of Age UK, one of the groups that funded the study, said, "We already knew that exercise is important in reducing our risk of some illnesses that come with ageing, such as cardiovascular disease and cancer. . . . [But] this research is exciting as it provides vital clues as to what impacts the way our brain ages and how we could tackle mental decline.

"[It] reemphasizes that it's never too late to benefit from exercise, so whether it's a brisk walk to the shops, gardening or competing in a fun run, it is crucial that, those of us who can, get active as we grow older."

Another recently frequently researched bit of interdependence links diet with mental functioning. A Mayo clinic study, for example, has found that a diet too high in carbohydrates hurts mental functioning as you age.

The findings published last year in the Journal of Alzheimer's Disease showed a 360 percent increase in mild cognitive impairment in people over 70 who eat foods high in carbs when compared to those who eat a diet high in protein and fat. One specific type of carb, sugar, was found by itself to increase the risk by 150 percent when the high-sugar consumers were compared to those who ingested the least amounts.

Initially the Mayo Clinic researchers worked with 1,230 people between the ages of 70 to 89. The 940 who showed no signs of unusual mental decline continued to be studied for the next four years.

At the conclusion, about 21 percent of them showed greater mental impairment than is associated with that age. From this, researchers were able to make the link between high carb ingestion and mental decline.

The link between a lack of sleep and weight gain is yet but another piece of proof of interdependence. An article published in last year by the journal SLEEP found that nine hours of sleep allowed 27 male and female subjects between the ages of 30 and 45 to eat less as compared to when they only slept four hours a night.

While the lack of sleep produced the same result in both men and women, it occurred for different reasons.

On four hours of sleep, the men produced more of the hormone ghrelin, which led to feelings of hunger, but the women's production remained the same. The women's production of a hormone called GLP-1, however, during the sleep reduction increased and produced the same lack of satiety.

Sleep quality and body weight are linked in yet another way. Those who are able to lose fat, especially belly fat, report a boost in sleep quality.

This study, first presented at the American Heart Association Scientific Sessions, put 77 subjects with type 2 diabetes or prediabetes on a six-month diet. Some also engaged in a prescribed exercise regiment.

The 55 subjects who continued in the study until the end lost an average of 15 pounds. Before-and-after questionnaires about sleep showed their sleep quality had improved about 20 percent, and that those who had managed to lose more belly fat reported the greatest improvement in sleep quality.