Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Some Mental Abilities Begin Decline in Late 20s: Study
Certain kinds of mental skills hit their peak at age 22 and then begin to decline at age 27, according to U.S. researchers who followed 2,000 healthy people, ages 18 to 60, for an average of seven years.
The study found that age 22 is when the brain reaches the high point in terms of speed of thoughts, ability to reason and visual problem-solving ability, CBC News reported. Test scores in these areas begin to decline at age 27.
University of Virginia psychology professor Timothy Salthouse and colleagues concluded that some "aspects of age-related cognitive decline begin in healthy educated adults when they are in their 20s and 30s."
But the researchers also found that vocabulary skills and general knowledge improved until age 60, CBC News reported.
The study was published in the April issue of the journal Neurobiology of Aging.
Fish Health Benefits Overstated: Analysis
The health benefits of eating fish have been overstated, according to Canadian researchers who conducted an analysis of available scientific data, the Globe and Mail reported.
Fish contain omega-3 fatty acids, a nutrient touted to help protect cardiovascular health. There's also widespread interest in the use of the oils for a number of other conditions, including dementia, cancer, multiple sclerosis and Crohn's disease.
But analysis lead author David Jenkins, a nutrition professor at the University of Toronto, said studies showing better heart health among people who eat fish regularly could be tilted by other factors. For example, people who eat fish generally have healthier lifestyles than other people.
Jenkins noted that vegetarians don't appear to have a higher risk of heart disease, even though don't consume animal proteins, the Globe and Mail reported.
The analysis was published in the Canadian Medical Association Journal.
Actress Natasha Richardson Hospitalized After Ski Accident
British actress Natasha Richardson is in critical condition after a skiing accident in Quebec. It's believed the 45-year-old Tony Award-winning actress suffered a head injury Monday at the Mont Tremblant ski resort north of Montreal, according to IrishCentral.com. and reported by the Associated Press.
She was taken to an emergency room at a local hospital and then transferred to Sacre-Coeur Hospital in Montreal. Her husband, actor Liam Neeson, reportedly left the set of a film in Toronto to be with Richardson, CBC News said.
Hospital officials refused to confirm whether Richardson was a patient there and said the hospital would have no comment until the actress' family releases more details, CBC News reported.
Richardson's aunt, actress Kika Markham, confirmed to BBC News that Richardson was in the hospital following a ski accident.
"We know that she has had an accident, but we really do not know any more details. We are very concerned," Markham said.
Richardson is the oldest daughter of Oscar-winning actress Vanessa Redgrave and the late director Tony Richardson.
Supreme Court Justice Ginsburg to Have Chemotherapy
U.S. Supreme Court Justice Ruth Bader Ginsburg, who had surgery in February for pancreatic cancer, says she will begin chemotherapy later this month.
She said the treatment is precautionary and doesn't expect to miss any court sessions, the Associated Press reported.
Ginsburg, 76, had surgery last month to remove a small cancerous growth from her pancreas. The cancer had not spread beyond the organ, test results showed. After she completes her chemotherapy, Ginsburg said she'll require only routines exams.
She had surgery for colorectal cancer in 1999 and underwent follow-up chemotherapy and radiation treatment, the AP reported.