Healthy Aging

There’s no scientific evidence that our bodies require two quarts or more of water daily. According to Heinz Valtin, MD, of Dartmouth Medical School, we only need lots of fluids in hot weather, during strenuous exercise, on long flights or when we have certain medical problems, such as kidney stones. Older people do need to be careful to drink enough liquids, though, because they may not feel as thirsty when they need water as they did when they were younger.

Chronic stress can make the very cells of your body age more rapidly. We know that because scientists have found a way to judge a cell’s age and vitality by examining its chromosomes. In a small but significant 2004 study, psychologist Elissa Epel, PhD, of the University of California at San Francisco, analyzed chromosomes in the white blood cells of 39 mothers who were under severe, long-term stress: each had a child with a serious, chronic illness, such as cerebral palsy. Epel found that the women who felt the most pressured had chromosomes that looked like those of someone 10 years older. There are many ways to manage stress, including meditation, yoga, vigorous exercise and more. If you’re not under stress, is it possible to slow down your aging rate? Scientists are working on that.

People who are isolated often have health problems. They also tend to live shorter lives than those who are more closely connected to friends and family. Loneliness differs from solitude. Some people like being alone and even see solitude as an important path to spiritual growth. But for others, loneliness and physical aging are a dangerous mix. A 2007, University of Chicago study of people middle aged and older found that those who were lonely produced more of the fight-or-flight hormone, epinephrine, indicating that they were chronically on edge. The researchers believe this would add to the normal wear and tear on the body.

Researchers at the University of Nottingham in England found that smoking interferes with the body’s ability to maintain its muscles on a day-to-day basis. In a 2007 study of women and men in their mid-60s, the investigators found that those who smoked produced larger quantities of biochemicals that break down muscle protein and inhibit muscle growth. The investigators believe this speeds up the loss of muscle mass that happens with aging and often leads to poor balance, falls and possible bone fractures.

Many of those who reach 100 or more are remarkably healthy and have been for most of their lives, according to the New England Centenarian Study. NECS researchers report that 9 out of 10 centenarians are relatively fit and independent in their early 90s, and about 3 out of 10 still are at 100. They seem to age more slowly than most people, and diseases that often accompany aging either never affect them or do so only late in their very long lives. Based on what he has learned from centenarians, Thomas Perls, MD, director of the study, believes that most Americans could live to their mid- to late-80s in good health if they didn’t smoke, did strength-training exercises and stuck to a diet that kept them lean.

Your best chance of achieving a long, vigorous life is to have good health habits early on and maintain them through midlife into your later years. However, it’s never too late. Richard S. Rivlin, MD, of Weill Cornell Medical College, reviewed more than 100 scientific studies done over the past 20 years and reported in 2007 that lifestyle changes can make a big difference to people even in their 60s and 70s. Lowering blood pressure through diet and exercise, for example, cuts the risk of heart disease more for older adults than for any other age group.

The amount of sleep you need remains relatively constant over your adult lifetime—generally seven to nine hours. But sleep patterns do change with age. Almost 20 percent of your slumber is deep and restful in your early 30s, but that drops to little more than 3 percent by your late 30s. Some people in their 50s find that they feel sleepy sooner in the evening and wake earlier in the morning than they used to. This reflects a shift in the body’s internal timing mechanisms. Still later in life, usually after age 70, sleep tends to become more fragmented, and many find that they wake more often in the night and are awake longer. There may also be a reduction in rapid eye movement (REM) sleep, the stage in which dreaming usually occurs.

Falling is the leading cause of deaths from injury in this age group. Every 35 minutes, someone 65 or older dies because of a fall. Many of those who survive never fully recover and can no longer live independently. The risk of being seriously injured in a fall increases with age, and older people who have fallen once are much more likely than others to do it again within a year. They often curtail their activities to avoid another accident, and that can create a vicious circle: because they’re less active, they’re less fit and more at risk than ever. What can you do to avoid falling? The Centers for Disease Control and Prevention recommends exercise and annual vision checks and suggests that you make sure your home has good lighting and no hazards underfoot. Also, if you are over 65, ask your doctor to review your medications for side effects or interactions that might make you more likely to fall.

You may actually need to take drugs in smaller doses than when you were younger. Many people begin to respond differently to medications once they’re about 75, and by 85 they’re particularly sensitive to high doses. Their bodies eliminate medications more slowly and they develop stronger concentrations in the blood. They’re two or three times as likely to react badly to drugs as younger adults are. The FDA says doctors should start older adults on substantially lower doses than younger patients and increase the amount gradually, if necessary.

In his book, Good Calories, Bad Calories (2007), science writer Gary Taubes maintains that there’s no scientific evidence that high-fat foods such as ice cream lead to heart disease and shorter lives. Taubes believes that the American diet of refined carbohydrates—sugar, white flour and white rice—is the root of the current obesity epidemic. A 2009 book, Fat and Cholesterol are Good for You, is just as critical of the fat-heart disease connection. Author Uffe Ravnskov, a Danish physician and researcher, marshals scientific evidence that there’s no correlation between cholesterol levels in the blood and clogged arteries. While both books are controversial, keep in mind that if you’re basically healthy, anything you eat in moderation, including ice cream, is unlikely to send you to an early grave.