The ups and downs of life may seem to have no predictable plan. But scientists now know there are very definite life patterns that almost all people share. Today, when we live 20 years longer than our great-grandparents, and when women mysteriously outlive men by seven years, it is clearer than ever that the "game of life" is really a game of trade-offs. (46. As we age, we trade strength for ingenuity, speed for thoroughness, and passion for reason. These exchanges may not always seem fair, but at every age, there are some advantages.) So it is reassuring to note that even if you’ve passed some of your "prime", you still have other prime years to experience in the future. Certain important primes seem to peak later in time.
WHEN ARE YOU SMARTEST? From 18 to 25, according to IQ scores; but you are more experienced with increasing age. You’re sharpest in your 20’s; around 30, memory begins to decline, particularly your ability to perform mathematical computations. "But your IQ for other tasks climbs," says Berkeley psychologist Arthur Jensen. Your vocabulary at age 45, for example, is three times as great as when you graduated from college. At 60, your brain possesses almost four times as much information as it did at age 21. (47. This trade-off between sharpness and wisdom has led psychologist Dr. Leopold Bellak to suggest that "maturity quotients" (MQs instead of IQs) be adopted for adults.)
WHEN ARE YOU HEALTHIEST? For men, from 15 to 25; for women 15 to 30.
"A man is in his best shape in the decade before age 25," says New York internist Dr. Donald Timkins. "His muscles are firmest, his resistance to colds and infection is highest, and his body is most efficient in utilizing nutrients." (48. Women, for reasons scientists do not understand, get a five-year bonus.) Peak health begins to decline when the body process called anabolism (cell growth) is overtaken by the opposite process, catabolism (cell death). "Cells have been dyingsince birth," says Tomkins, "but in our late 20’s, they start dying faster than they are replaced." Also, muscle is replaced with fat.
WHEN ARE YOU HAPPIEST? You have the best physical sense of yourself from 15 to 24; the best professional sense from 40 to 49. Pessimism peaks between 30 and 39. San Diego State University psychologists Marilyn Borges and Linda Dutton found that before age 24, we believe that our happiest years are yet to come; over 30, we believe that they’ re behind us. (49. The pessimism peak occurs when we realize that talent and determination aren’t enough to guarantee success.)Lady Luck must help.
Also, youth’s good physical sense of self apparently does little to foster happiness. "Parents who tell their teenage children these are the happiest years," says Ligger, "couldn’t be more wrong. Adolescence is very difficult. Only when you are 40 and looking back does youth look blissful."
By viewing life’s various peaks, we can easily get the feeling that we are part of a giant give-and-take plan. (50. Though statistically the plan is there, we must remember that every peak has many exceptions. Says McLeish, "The human life journey cannot be charted by a single curving line.")