Twenty-five percent of men experience hair loss as early as age 21. According to the American Hair Loss Association, 66% of men will experience appreciable hair loss by 35 and by 50 almost 85% will have significant hair thinning. Male pattern baldness – the most common type of baldness – is 95% genetic and can be passed down by either parent. Non-genetic causes for hair loss include medication and severe stress or illness, as well as nutrient deficiencies like protein, calcium and iron. These things also cause hair loss in women, as does childbirth – in spite of it often being a "hair-raising" experience.

However, women are more affected by alcohol than men are. Men's and women's physical differences cause them to metabolize alcohol differently. Women are smaller in size, so their internal organs are more exposed to alcohol. Women's bodies contain more fat and less water than men's, so their bodies dilute alcohol more gradually. Women also have much lower levels of the enzyme "alcohol dehydrogenase", which helps break down alcohol. Thus women absorb about 30% more alcohol into their bloodstreams than men do. Women experience the effects of alcohol more quickly and longer – information women need to drink … in.

For both men and women birth order shapes their lives. In 1972 birth order experts researched how many firstborns were in the U.S. Congress. Out of 121 congressmen and senators in the sample, 51 were firstborns, 39 were middle children and 31 were youngest children. Since then several studies have found there are more firstborns in high-achieving professions like corporate CEO's, college professors, U.S. presidents and Supreme Court justices. There's also evidence firstborns are 3 IQ points smarter than second-born siblings. These differences were attributed to "undivided parental resources" – making it necessary for younger siblings to be more … resourceful.

Nevertheless, the happiness of both men and women may depend on their spouses. In a study published in the journal Developmental Psychology, researchers analyzed responses from 178 married couples in data from the Seattle Longitudinal Study, a study that has followed over 6,000 people since 1956. What the researchers discovered was an individual's happiness is closely linked to their spouse's – especially in long-term married couples. When the happiness level of one spouse went up, so did the other's and vice versa. It seems "For better, for worse, for richer, for poorer, in sickness and health" basically means in happiness and unhappiness.

Knight Pierce Hirst has written for television, newspapers and greeting cards. Now she writes a 400-word, news blog three times a week. KNIGHT WATCH, a second look at what makes life interesting, takes only seconds to read at http://knightwatch.typepad.com