Every week, we’re bringing you a roundup of the latest health and wellness news to hit the wire. This week, we look at how exercise helps you fight health problems associated with aging, how a ketogenic diet could help fend off the flu, and news about chemical hair products and increased breast cancer risk.

How exercise keeps your muscles young

An interesting new study covered by The New York Times showed the effect that regular exercise throughout adulthood had on the body’s ability to protect itself from age-related loss and damage later.

Thigh muscle tissue samples from older men who had started exercising during the running boom of the 1970s showed a resemblance to samples taken from 25-year-olds, and these muscles were found to weather inflammatory damage better than those taken from sedentary older people.

Almost all of us begin to lose muscle mass and strength around middle age, with the process accelerating as the years go on, in part due to an age-related increase in inflammation.

Physically fit people tend to have less inflammation in their bodies than inactive people, so researchers at Ball State University wondered would they also have less muscle loss as they age? And what could these super seniors tell us about optimal muscle aging?

They measured muscle mass and took blood and tissue samples. Here’s what they found out about these active seniors:

  • In terms of muscle mass, while the active older men had smaller thigh circumferences than the men in their 20s, they were larger than the sedentary seniors.
  • When samples were taken after completing a lower-body weight session, inflammation levels in the older active men—while higher than those of the 20-year-olds—showed far less inflammatory activity and quicker anti-inflammatory reactions than the sedentary adults.

Researchers say this indicates that long-term exercise helps muscles remain healthy by readying them to dissipate inflammation, professor of exercise science and lead author Todd Trappe, Ph.D., told the Times.

And conversely, remaining sedentary sets up muscles to overreact to strain, possibly leading to smaller gains when someone does exercise. Of course, Trappe said, this should not discourage middle-aged people or seniors from beginning an exercise program. While inflammation might be more troublesome at first, your muscles will eventually grow and more closely resemble those of the lifelong exercisers if you stick with it.

The ketogenic diet helps fuel the immune system

The high-fat, low-carb keto diet is gaining plenty of fans for weight loss, but researchers say it may come with another surprising perk, as well—a greater ability to fight influenza.

Mice that were fed a ketogenic diet were better able to combat the flu virus than mice fed food high in carbohydrates, according to a new Yale University study published in the journal Science Immunology summarized on ScienceDaily.

The diet, which includes meat, fish, poultry and non-starchy vegetables, activates a subset of T cells in the lungs not previously associated with the immune system’s flu response, increasing mucus production from airway cells that more effectively trap the virus, researchers reported.

The keto mice had a higher survival rate than those on the high-carb normal diet because the low-carb diet triggered the release of gamma delta T cells, which produce helpful mucus in the cell linings of the lungs, while the high-carb diet does not.

Hair dye and breast cancer risk

Scientists at the National Institutes of Health found that women who regularly use permanent hair dye and chemical hair straighteners have a higher risk of developing breast cancer than women who don’t use these products, and that risk increased with more frequent use of these chemical hair products.

Using data from 46,709 women, researchers found that women who regularly used permanent hair dye in the year before enrolling in the study were 9 percent more likely than women who didn’t use it to develop breast cancer, with the risk significantly higher in black women.  Moreover, the study found that women using hair straighteners at least every five to eight weeks were about 30 percent more likely to develop breast cancer.

The research team found little to no increase in breast cancer risk for semi-permanent or temporary dye use.

Researchers identified a few potential culprits, according to MarketWatch, such as formaldehyde, a known carcinogen that is an active ingredient in Brazilian keratin straightening treatments, as well as aromatic amines, which are colorless chemicals in permanent dye that have been found to bind with breast tissue DNA—possibly damaging the DNA and leading to cancer.

Permanent dyes have higher concentrations of these aromatic amines than the semi-permanent dyes do, which may be why the temporary dyes didn’t show the same increased risk of cancer.

Photo credit: Group4 Studio, Getty Images