The Longest-Living Sex - and Why

Robert W. Griffith, MD
July 16, 2004

Professor Thomas Perls of Harvard Medical School is the founder of the New England Centenarian Study (NECS); this study reports on the heath of some of the United States' oldest citizens. He has distilled the most interesting results in his book "Living to 100". Here is the 4th in our series of extracts from the book. Robert Griffith, Editor.

The Longevity Marathon - Who Lasts Longest?

Eighty-five percent of the centenarians in our study are women, which is consistent with the general centenarian population. Worldwide, centenarian women outnumber centenarian men by about 9 to1. Not only do women have the advantage in numbers, they also hold the most important record in the longevity marathon: the longest life. As we pointed out before, the oldest person in recorded history is a woman, Mme Jeanne Calment, who died in 1997 at the age of 122.

In all developed countries and most developing ones, women have greater life expectancy than men, sometimes by a margin of as much as 10 years. In the United States, life expectancy is about 79 years for women and about 72 for men. The difference has become more pronounced in this century as female life expectancy has increased faster than that of males. Since 1900, the average national increase in life expectancy in developed countries as has been 71% for women, and 66% for men. Women over age 65 outnumber men by a ratio of three to two.

Men are Stronger, Taller, Richer . . .

The longevity of women is surprising, given that men enjoy numerous physical and cultural advantages over women. In most aspects of biological and social life, men appear to hold of the trump cards. In worldwide competitions like the Olympics, men are stronger and faster than women. They are taller on average, and less likely to be overweight. Men typically have access to more money than women and receive more prompt medical care for certain potentially lethal medical conditions like heart disease. In contrast, older women are the single poorest group in America and often have no one to depend on; 35% live alone and 52% are widows, whereas among older men, only 14% live alone and 23% are widows.

One would expect that the group of people with comparatively lower access to wealth, employment, health care, and education would have a shorter life expectancy than another group with more of these privileges. In various societies the stereotypical image of women is one of delicacy and dependence, not one easily equated with survival over the long haul. Expressions used to describe strong women are often derogatory, or are simply paradoxical: "steel magnolia," for instance. The average woman is supposedly crippled in society without the support and companionship of a man. Indeed, when our study subjects were born, women did not yet even have the right to vote. Yet the disadvantages that have been women's lot seem only to have made them stronger. For the most part, women just age better.

The Stages of the Marathon

The idea behind the longevity marathon isn't to run faster or jump higher; people simply want to stay in the race as long as they can and with as much good health as possible. As we began handicapping the longevity marathon, it appeared to us that men and women were running two different races. Despite their size, speed, and strength, men just seem to die more easily and frequently than women -- even in the womb. Boys are conceived far more frequently than girls -- about 115 male conceptuses for every 100 females. From that point on, however, women quickly make up ground, and they soon surpass men handily. For some reason, male fetuses are miscarried, stillborn, or spontaneously aborted more often than female fetuses. Consequently, by the time of birth, the ratio of boys to girls has dropped to 104 boys for every 100 girls.

Childhood to the Mid-Twenties

It doesn't stop there, though. Boys die more frequently than girls in infancy, during childhood, and during each subsequent year of life. Male mortality accelerates considerably during certain stages of the longevity marathon. Puberty brings on a flood of behavioral changes that can spell disaster for men. It is the beginning of what some call "testosterone toxicity." With the increasing production of the male hormone testosterone, boys start taking more risks than girls, thus increasing the odds that more of them will die.

These hormonal changes have only been exacerbated by the proliferation and availability of drugs and technology, both licit and illicit: faster and cheaper automobiles, and more automatic weapons, for example. During and after puberty, the causes of death are much more varied and visible among men than women. Alcoholism and death from automobile motorcycle accidents are each three times as common among men. Men also have high rates of infection with HIV, the virus that causes AIDS. Between the ages of 15 and 24, male risk-taking and recklessness translates into a mortality rate three times higher than women of the same age. By the time we've run 2½ 10-year laps of the longevity marathon, to age 25, the numerical male advantage has disappeared, and surviving females outnumber males.

Young Adulthood to Baby Boomer

A new round of hurdles [for males] appear after the fourth lap, when an increasing number of men in their forties start to see symptoms of heart disease, due in large part to their greater rates of smoking. Over the next two or three laps, men face huge obstacles. Men aged 55 to 64 are twice as likely as women of the same age to die from heart disease and accidents, and four times as likely to commit suicide. Other illnesses related to smoking and alcohol consumption -- like lung cancer and cirrhosis -- also kill more men than women in this age group.

Women, on the other hand, are still cruising around the track in their fifties and early sixties, with relatively few hurdles in their way. Since puberty and the beginning of menstruation, they have been producing large amounts of estrogen which has beneficial effects on cardiovascular health, including lower total cholesterol levels, lower LDL cholesterol, and increased HDL cholesterol.

The Sixties and Seventies

Because of their estrogen edge, women don't hit the heart disease hurdle until after the sixth lap, when women in their sixties begin to experience the cardiac ramifications of menopause. As estrogen decreases, women's cardiovascular systems become more susceptible to disease. Although women face the hurdle of cancer alongside men, their risk of lung cancer has been historically lower because fewer women have smoked. This may change in the coming years as male smoking has decreased. The incidence of lung cancer among women has increased 400% since the early 1970s, primarily due to an increase in the number of women who smoke cigarettes.

Men face the steepest hill of the longevity marathon during their sixties and seventies. These are the years when cancer, heart disease, diabetes, Alzheimer's disease, and stroke are most likely to strike and kill, and they drastically thin out the numbers of men who can go on to the next few laps. During these two crucial decades, women appear much healthier than men by almost all measures.

Eighties and Beyond - the Goal in Sight

But during the 9th and 10th laps - the eighties and nineties - we saw a new pattern occurring. The hurdles women had to vault started to come thicker and faster. Alzheimer's disease, stroke and heart disease frequently blocked the path to 100 for women. But for men, the opposite appeared to be occurring. These same diseases had menaced men in the earlier laps of the male track. For the men who encountered them, they had been insurmountable obstacles that caused them to drop out of the race. But the men who had not run into these obstacles in their sixties and seventies seemed somehow "immune." As we had seen in our earlier studies, if men hadn't developed heart disease or cancer by around age 80, they probably had avoided these diseases completely. They had run the most treacherous parts of the race unscathed. Now, in a sense, the track sloped slightly downhill for men, and became easier to negotiate. We began to speak of them as having "gotten over the hump." [Such men] are aging stars, gifted with a much lower risk of heart disease, dementia, cancer or other chronic diseases. They reach extreme age because they effortlessly vault over the obstacles that force other men out of the longevity marathon. Women, we were beginning to see, do not need to age quite as well as men in order to live to 100. They can survive with some illnesses. But for men to remain in the longevity marathon, they have to be all-star aging athletes.

In the next extracts from his book, Professor Perls discusses some additional reasons for the differences between the sexes in their longevity profiles. You can buy his book "Living to 100" at Amazon; click here

Source

• Living to 100: Lessons in Living To Your Maximum Potential at Any Age. TT. Perls, MH. Silver, 1st edition, Basic Books, New York, NY, 1999

Related Links
What Centenarians Can Tell Us
Women at Cardiovascular Risk
How Does the Mediterranean Diet Promote Longevity?
Aging Well: The Complete Guide to Physical and Emotional Health

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