A 2007 study found that both red and white wines are effective anti-bacterial agents against strains of Streptococcus. A 2008 study posits that moderate consumption of red wine may decrease the risk of lung cancer in men.

Wine's effect on the brain is also under study. One study concluded that wine made from the Cabernet Sauvignon grape reduces the risk of Alzheimer's Disease. Another study concluded that among alcoholics, wine damages the hippocampus to a greater degree than other alcoholic beverages.

Red wine consumption spiked in the 1990s after 60 Minutes and others reported on the French paradox. The French paradox is the unexpectedly low incidence of heart disease in the country that consistently consumes higher levels of saturated fat. Is wine the reason? The evidence is still inconclusive.

Population studies have observed that heavy drinkers have an elevated risk of heart disease, while moderate drinkers (two glasses of wine a day) have a lower risk than non-drinkers. Studies have also found that moderate consumption of other alcoholic beverages may be cardio protective, although the association is stronger for wine. Red wine may convey more health benefits than white, containing more polyphenols, thought to be particularly protective.

Resveratrol, a chemical in red wine, slows aging, death, weight gain, and diabetes in animal studies. Low doses of resveratrol mimic the effects of what is known as caloric restriction - diets with 20-30 percent fewer calories than a typical diet, prolonging life and health. Resveratrol is produced naturally by grape skins during fermentation.

Other beneficial compounds in wine include other polyphenols, antioxidants, and flavonoids. Red wines from the south of France and from Sardinia in Italy have the highest levels of procyanidins, which are compounds in grape seeds which may be responsible for red wine's heart benefits.

Resveratrol appears to inhibit the development of fat cells and have other anti-obesity properties, according to a report from researchers at the University of Ulm in Germany. The findings show that in laboratory experiments with so-called “pre-fat cells,” resveratrol prevented them from converting into mature fat cells. Resveratrol also hindered fat storage in the cells.

“Resveratrol has anti-obesity properties by exerting its effects directly on the fat cells,” said the study’s lead author, Pamela Fischer-Posovszky, a pediatric endocrinology research fellow in the university’s diabetes and obesity unit. “Thus, resveratrol might help to prevent development of obesity or might be suited to treating obesity.”

Excessive consumption of alcohol can cause cirrhosis of the liver and alcoholism. The American Heart Association cautions people to "consult your doctor on the benefits and risks of consuming alcohol in moderation." Pregnant women should avoid alcohol, since it causes fetal alcohol syndrome in the embryo. Alcohol crosses the placental barrier and can stunt fetal growth or weight, create distinctive facial stigmata, damage neurons and brain structures, and cause other physical, mental, or behavioral problems. The current recommendation of the US Surgeon General is not to drink at all during pregnancy.