Aerobic exercise is no friend to breast tumors, says a new study that suggests that regular physical activity may be a “novel adjuvant treatment” for women with breast cancer.

Research conducted on mice found that a body that gets regular physical activity is a more hostile environment for cancer’s growth in breast tissue than is a sedentary body. And once breast cancer has gained a foothold, regular aerobic exercise makes a tumor more vulnerable to the effects of chemotherapy.

The study, published in the Journal of the National Cancer Institute, echoes earlier work by the same authors on the effects of exercise on prostate tumor growth and treatment.


Diet soda is tied to belly fat

Researchers examined data taken for nearly 10 years from 749 Mexican-Americans and European-Americans ages 65 and older in the San Antonio Longitudinal Study of Aging.

They determined that daily and occasional diet soda drinkers gained nearly three times as much belly fat as non-drinkers. The diet soda drinkers added an average of .83 inches to their waist circumferences, while the non-drinkers added .3 inches. Daily consumers gained a striking 1.19 inches. Men, European-Americans, people with a body mass index greater than 30 and people who did not have diabetes fared the worst.


Fat stigma studied in smell test

Experimental subjects who were tricked into thinking they should smell something reported they smelled less pleasant odors when they viewed pictures of overweight and obese people than when they looked at trim people, research has found.

The exercise, conducted by psychology professors at the University of California, Los Angeles, is a way to smoke out “implicit association” — or prejudice that lies beneath the level of conscious awareness. While similar exercises have been used to explore racial and other forms of prejudice, heavy people in this case were shown to receive the stigma.

The findings “suggest that the extent of negative bias toward overweight individuals may be greater than previously assumed,” the authors of the study wrote.


Broken arms may heal on own

Broken arms are routinely treated with surgery, but a randomized trial has found that many breaks can be allowed to heal on their own.

Researchers studied 231 patients admitted to British hospitals for displaced fractures of the humerus, the bone that connects shoulder to elbow. In a displaced fracture, the bone is separated and out of its normal position.

The researchers randomly assigned 114 to surgery and 117 to simply immobilizing the arm in a sling. The study, published in JAMA, followed patients for the next two years, examining them at regular intervals.

Overall, the surgical and nonsurgical groups had similar outcomes, with no difference on measures of pain and comfort. But heart, respiratory and other complications were more common in the surgery group.

News services