We went to a presentation by professional nurses who assist people in dealing with chronic disease, especially diabetes and prediabetes.
We were told that the pancreas has "beta" cells that create insulin and in some people, they lose function and the insulin supply is too low to convert the blood sugar (glucose) into energy. I have read that the insulin ushers glucose into the cells where it can be converted. If too much blood sugar is left in the blood, it results in the several very nasty effects of the disease of diabetes, like loss of a limb or eyesight or death by diabetic coma. Diabetes is the 7th leading cause of death in the US, killing 69,000 people in 2010.
They asked me specifically to sum up what I had learned from the presentation. I said that just about every slide mentioned weight loss. Except for mentioning health benefits of weight loss and the words "portion control", just about nothing was said that really helps. I mentioned that Lynn and I have tried the 5:2 diet with good success.
There doesn't seem to be very good agreement between different approaches. I keep hearing from older people, including a nurse, that older people should not be too thin, that they need "physical resources" if they get sick. I suspect that how much fat helps is murky as is how often such a resource actually helps. I can see that as people age and their ability to exercise drops as well as their desire to be swimming suit models, there is both lack of body means to exercise and motivation. But these nurses said that the body mass index is best at 19 to 23. I have read several times that 25 is the standard for most people and that people 65 and over should aim for between 25 and 30. Even a slight change in the body mass index translates into enough body weight difference to matter, maybe to be depressing.
The nurses drew a distinction between digestion (moving the food through the body and extracting the nutrients in it) and metabolism (converting the nutrients into energy for breathing, digestion, heartbeat and circulation and movement). I am interested in what can be said and done to allow old people to have good levels of energy. That, too, seems to be a murky and complicated subject. I found this in the Oprah magazine:
How much can one person's metabolism differ from another's?
If age, gender, height and body composition are the same, the variation in resting metabolism is likely to be less than 3 percent, according to Steve Smith, M.D., an Assistant Professor of Endocrinology at the Pennington Biomedical Research Center of Louisiana State University. For example, if two equally active 38-year-old women are both 5'5" and weigh 130 pounds, one might have a daily RMR of 1,800 calories and the other, 1,854 calories—an increase that only buys the second woman about two walnuts per day.