Wednesday, September 22, 2004
It is never too late to eat well and exercise every day, according to four new studies that found healthy lifestyles can produce dramatic benefits for the body and mind even among the elderly.
...One of the studies found that elderly people who ate a healthful diet, exercised regularly, drank alcohol moderately and avoided smoking slashed by more than half their risk of dying from any cause, while another found that the same diet improved blood-vessel function and reduced inflammation. The two other studies produced the strongest evidence yet that simply walking every day goes a long way toward keeping the mind sharp and warding off dementia, including Alzheimer's disease.
Actually, the data aren't as impressive as the news reports are making them out to be. The first study followed 2,339 European seniors ages 70 to 90 for ten years. Forty-percent of them died during that time. Periodically, they would answer questionairres about their eating, drinking, smoking, and exercising habits.
A "Mediterranean" diet was a diet higher than average in legumes, fruits, vegetables, monounsaturated fatty acids, nuts, grains and fish, but lower than average in meat and dairy products. It was healthier to drink than to teetotal, healthier to never smoke or to have quit fifteen years ago, and healthier to walk the equivalent of thirty minutes every day. Assuming that the study subjects answered their questionairres truthfully and accurately, which is a big assumption, they were rated on a score of 0 to 4 in terms of health, with one point for each category. The higher the score, the healthier the lifestyle.
The absolute mortality rates over the ten year period in this very elderly population were 66% for those with the lousiest lifestyles (a score of 0 to 1), 60% for the moderately lousy (score of 2), 56% for the moderately healthy (score of 3) and 56% for the healthiest lifestyles of all (a moderate non-smoking drinker who exercises daily and eats Italian-style.) The most important factors influencing longevity during this ten year period were cigarette smoking and exercise. Diet and alcohol were a little less influential. And while the difference between the 66% mortality rate for tobacco-puffing, couch-potato teetotaling cheese-burger eaters and the 56% mortality rate for athletic, non-smoking, pasta and wine afficionados is significant, it's impossible to tell from the study what contribution the diet makes. It also isn't "dramatic" - the word I heard used on NPR this evening to describe the results.
The second study took 180 patients diagnosed with the metabolic syndrome and put one half of them on a "Mediterranean diet" and one half on a diet of their choice. The biggest difference between the two groups was that those on the Mediterranean diet were given detailed instructions, counselling, and encuragement in their diets. Those in the control group were just given general instructions about healthy food choices. After two years, those on the Mediterranean diet had lower average blood sugars, lower trigycleride levels, (by twenty points), lower insulin levels, and smaller waists. The diet had their metabolic syndrome symptoms, at least by a little bit. But the study didn't look at mortality at all.
And what about dementia and exercise? There were two studies that looked at that relationship. One was devoted to elderly men, the other to elderly women. The study in men involved 2257 Hawaiian men who reported their physical activity from 1991 to 1993. They were then examined for dementia from 1994 to 1996 and again in the time period from 1997 to 1999. The study didn't find out if their activity levels had changed since the intial evaluation, but among those who walked less than one quarter of a mile a day from 1991 to 1993, eight per cent developed dementia. Among those who walked over two miles a day, four percent developed dementia. It's not a huge difference, but it does show a small benefit for those who exercise.
The women's study looked at the physical activity and mental dexterity of 18,766 elderly nurses (ages 70 to 81) from 1986 to 2003. Unlike the study in men, the researchers asked the women about their physical activity every two years during the study. They then performed mental status tests over the telephone on two occasions at two year intervals in the final four years of the study. The women had to do such things as recall parapgraphs, name as many animals as they could in 1 minute, and count backwards. The researchers gave the women scores based on their performance and combined them into their own scoring system which only they completely understand. The women who exercised the most vigorously performed better on the telephone exams than those who did not exercise, but we have to take their word for it when they tell us the results were significantly different.
There's no doubt that staying active is important in living a satisfying life in the twilight years. Joints stay nimbler, balance is better, and overall satisfaction with life is better for those who make an effort to keep moving. Spending your old age in front of the television (or computer) causes joint stiffness and social isolation. But does it stave off Alzheimer's? If it does, not by much.
P.S. For those of you who are interested, here's some information on the the Mediterranean diet. For the metabolic syndrome study the diet consisted of the following:
<30% total fat (saturated fat <10%)
cholesterol consumption <300mg/day
And more specifically, eat at least:
250-300g fruits each day
400g whole grains (legumes, rice, maize, wheat)
Use olive oil
Personally, that seems like an awful lot of mental effort to put into eating.
posted by Sydney on 9/22/2004 07:40:00 AM 0 comments