Hormones good for Heart
Older men with naturally low levels of the testosterone are at higher risk of heart attacks than men who have high levels of the hormone. A study of 2,400 Swedish men in their 70s and 80s showed that those with naturally higher levels of testosterone suffered fewer heart attacks or stroke over the next several years than those with lower levels of the hormone, reported the Journal of the American College of Cardiology.
After accounting for health factors, men in the highest-testosterone group still showed a 30% lower risk of heart disease or stroke compared with the other three-quarters of the study group.
Too much booze blunts immunity
Too much alcohol weakens your immune system and could make you much more vulnerable to viruses, including HIV. To see how alcohol affects resistance to infection, researchers exposed monocytes to chemicals that mimic viruses and bacteria. Half of the cells were soused in the levels of alcohol that a person has in his blood after quaffing four or five alcoholic drinks daily for a week.
Alcohol blunted the monocytes' defences, reported at the University of Massachusetts Medical School in Worcester. When the over-the-limit cells were exposed to a virus mimic, they produced only a quarter of the virus-fighting molecule called type-1 interferon (the first response to infection) as teetotal monocytes.
Stress shrinks the brain
Prolonged stress of loveless marriages, dead-end jobs and post-traumatic situations can shrink the brain and cause dementia.
Chemicals called corticosteroids, which aid the "fight or flight" response, can kill off brain cells if the concentrations remain high over long periods. The hippocampus, a part of the brain involved in forming memories, is particularly susceptible. The discovery first came about after doctors treated Wall Street bosses for post-traumatic stress after the September 11 attacks. Brain scans showed that the executives' hippocampuses had shrunk to the size of those of elderly people suffering from dementia.