It Only Takes A Little

Three related articles were published yesterday in the USA Today:

1) Excessive Sitting Linked To Premature Death In Women

Research released last fall found that women who sat for more than six hours a day had a 37 percent increased risk of premature death, compared to 18 percent for men. Those results stayed the same, even when factors such as an individual's diet, amount of physical activity and smoking were taken into account.

Dr. Alpa Patel, senior epidemiologist at the American Cancer Society, is the lead author of that study, the largest on how sitting affects mortality. The study was based on information from surveys of 123,000 people who participated in the study between 1992 and 2006.

Females who sat the longest and exercised the least had twice the risk of death compared with women who recorded more activity and less sitting. Under similar circumstances for men, there was only a 50 percent greater chance of death.

Patel can't explain why sitting may be more hazardous to women's health. It's unclear whether the varying results are caused by gender, or if there's some other influence at work.

2) Too Much TV May Take Years Off Your Life

Researchers in Australia found that people who averaged six hours a day of TV lived, on average, nearly five years less than people who watched no TV.

For every hour of television watched after age 25, lifespan fell by 22 minutes, according to the research led by Dr. J. Lennert Veerman of the University of Queensland.

But other experts cautioned that the study did not show that TV watching caused people to die sooner, only that there was an association between watching lots of TV and a shorter lifespan.

Though a direct link between watching TV and a shortened lifespan is highly provocative, the harms of TV are almost certainly indirect, said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine.

"As a rule, the more time we spend watching TV, the more time we spend eating mindlessly in front of the TV, and the less time we spend being physically active," Katz said. "More eating and less physical activity, in turn, mean greater risk for obesity, and the chronic diseases it tends to anticipate, notably diabetes, heart disease and cancer."

3) Studies Show 15 Minutes of Daily Exercise Makes A Big Difference

Don't despair if you can't fit in the recommended 30 minutes of daily exercise. Growing evidence suggests that even half that much can help.

It's still no excuse to slack off. Regular exercise strengthens muscles, reduces the risk of some diseases and promotes mental well-being. The more exercise, the better.

But not everyone has the time or willpower. So researchers set out to find the minimum amount of physical activity needed to reap health benefits. The findings by a study in Taiwan suggest just 15 minutes of moderate exercise a day can lead to a longer life.