Smile, and take a deep breath. Study results presented at the 98th International Conference of the American Thoracic Society and published in Internal Medicine News show that persons with an optimistic outlook on life have better lung function than pessimists. The study followed 755 men for an average of 7.3 years and found that pessimists had a 4 percent greater loss of lung function than optimists after controlling for possible confounders, including age and smoking status. According to the presenter of the findings, a similar loss in lung function might be found in a person who had smoked one pack of cigarettes a day for 20 years.

First aid–related sales are booming, thanks in part to consumer demand for technologically advanced products. According to the findings of a report prepared by Mintel International Group, 134 new products were introduced last year, and more growth is expected this year. Items now available to consumers include some developed to reduce the appearance of scars as well as antibiotic, waterproof, and “hurt-free–removal” bandages. In the future, more complex products may also be on store shelves, such as bandages that can “sense” specific bacteria, indicating the presence of infection.

A banana a day may keep the risk of stroke away. Insufficient potassium levels may increase a person's risk of stroke, according to a study published in Neurology. The study followed 5,600 men and women older than 65 years and kept track of strokes for up to eight years. Patients with the least potassium in their diets were more likely to have a stroke than those with the most potassium in their diets. This news is particularly important to patients taking diuretics, which eliminate potassium from the body. The study shows that patients taking diuretics who have the lowest potassium levels are more likely to have strokes than patients who have the highest potassium levels.

Something as simple as a dog collar could save the health of humans and dogs. According to a study published in The Lancet, outfitting dogs with collars that are saturated with insecticide could decrease cases of visceral leishmaniasis by 43 percent in humans and 54 percent in dogs. Approximately half a million people are infected each year with this disease, which passes from sand flies to dogs to humans. Unsuccessful previous efforts against the disease had centered on spraying houses with insecticide and killing stray dogs that might be carriers of the disease. If left untreated, the disease can be fatal, though most cases in humans are subclinical.

Warning: cigarettes may be harmful to your cat. A study published in the American Journal of Epidemiology shows that cats whose owners smoke are three times more likely to develop lymphoma than cats living with nonsmokers. Researchers studying 80 cats with lymphoma and 114 cats with renal disease found that all cats exposed to tobacco smoke had a higher risk of lymphoma. This risk is directly related to the amount of smoke in the house and the length of time the cat has been exposed to it.

A taste for salt in babies may be related to elevated blood pressure, according to a study published in Hypertension. Researchers gave 234 newborns small drops of a water-and-salt mixture and found that the babies who had the most favorable response to the salty taste also had slightly higher blood pressures. The link was most notable in babies with at least one grandparent who had a history of hypertension. No connection was found when researchers performed a similar test with a sweet-tasting solution.