No matter what your weight or physical condition, exercise can help lengthen your life. That’s according to a new study by University of South Carolina researchers that finds fitness – rather than fatness – predicts how long you’ll live.

Exercise physiologist Steven Blair and his colleagues recently reported in the Journal of the American Medical Association that overweight and obese seniors who were physically fit outlived their contemporaries – yes, even the lean ones – who weren’t physically active. And if you haven’t been active for a long time, don’t worry about signing up for a marathon. Start with sparks of activity, such as just walking 10 minutes at a time. Even this exercise can add up to significant health benefits, Blair found.

Study finds benefit of low-fat dairy products

The question: Some studies have shown that calcium and Vitamin D can aid in lowering blood pressure. Does it matter whether the source of the nutrients is dairy products or supplements?

The latest: This study analyzed data on 28,886 women who averaged 54 years old and did not have high blood pressure or heart disease at the start of the study. During a 10-year span, hypertension was diagnosed in 8,710 of them. Overall, the more dairy products the women reported consuming, the less likely they were to have developed high blood pressure. Those who took in the most calcium through their diets reduced their risk of hypertension by 14 percent; and those who had the highest levels of dietary Vitamin D consumption saw a 7 percent reduction in risk. Nearly all of the benefit stemmed from consumption of low-fat dairy products; eating high-fat dairy products did not affect the risk of hypertension, nor did calcium and vitamin D intake from supplements.

Who may be affected? Middle-aged and older women. About a third of all American adults have high blood pressure. Among those older than 55, it’s more common in women than men.

Caveats: Diet and supplement data came from the women’s responses to questionnaires; the study authors calculated nutrient intake for foods the women reported eating. Exposure to the sun, a prime source of Vitamin D, was not included in the analysis.

Find this study: Feb. 7 online issue of Hypertension.

Pot smoke may ruin a smile

It may not just give you a bad case of the munchies: Regular marijuana smoking appears to increase young adults’ risk of gum disease, a problem typically associated with aging.

As part of a long-term health study, a team led by researchers at the Dunedin School of Medicine in New Zealand followed about 900 people born in 1972 and 1973 to assess the effects of marijuana on periodontal disease.

While it is well known that cigarette smoking and spotty use of dental services are risk factors for gum problems that can lead to inflammation and eventual tooth loss, the role of marijuana alone had not been examined previously.

The researchers divided participants into three groups: About 33 percent did not smoke pot, 47 percent smoked fewer than 40 times per year, and 20 percent smoked more than 41 times per year, beginning at age 18. All had dental checkups at age 26 and 32.

Overall about 42 percent showed some signs of periodontal disease at 32. After controlling for dental checkups, tobacco use and presence of plaque, researchers found that about 24 percent of the heaviest smokers showed some signs of gum problems, compared with 11 percent of infrequent users and 6 percent of those who did not smoke pot.