But who wants to live to age 100? Surprisingly, 61 percent of Americans say they would like to join the centenarian group, but only if they would have a high quality of life and could afford to live that long. They might get their wish. If forecasts are correct, one million Americans will be centenarians by the year 2080. Hopefully by then scientists will have figured out how to keep men alive as long as women, who historically have outlived men by several years. Ken Dychtwald, author of Age Wave and other books on the sociology of aging, believes that in the not-too-distant future we will be likely to think of old age as setting in at around 90 or even 100.

How can we account for today's extended longevity? Science and medicine deserve much of the credit, having conquered many deadly diseases, and scientists are still working to defeat two current leading causes of death—cardiovascular disease and cancer.

But there are other factors that contribute to long life, including genetics, environment, lifestyle, physical and mental fitness, diet, exercise, attitude, stress level and social ties.

At her 100th birthday party, a local elder was asked by a crowd of well-wishers to reveal her secret for attaining 100 years of life with health, wisdom and good humor. She was well-known for walking up to a mile to make weekly visits to homebound seniors and convalescent hospital residents many years her junior. The day before her birthday party, the centenarian presented her monthly, one-hour-long review of a current bestseller to a crowd at the local senior center.

A frequent and eloquent speaker, the centenarian needed only four words to tell her secret: "Shun regrets. Go forward."

Positive attitude is a common trait among those who attain the 100-year mark.

If you haven't yet made your New Year's resolutions, here are a few worth considering for 2003—they might put you in the running for 100 candles on your cake.

The first rule has been around since the U.S. surgeon general first advised Americans 50 years ago to quit smoking. It is never too late. Even if health has already deteriorated, quitting smoking extends life.

Maintain a reasonable body weight. Obesity can be as risky and as hard on health as smoking. An increase of one pound a year can result in cholesterol changes that bode badly for the arteries. Scientists have proven that rats and other animals flourish on a low-calorie diet of nutritious foods with high vitamin, mineral and protein content. The underfed animals were healthier and lived longer—even twice as long as animals fed a higher calorie, balanced diet.

Studies throughout the last century have found that diet plays a significant role in heart disease. Dr. Ancel Keys, who at age 98 formulated the K rations used in World War II, followed his own prescribed diet of deeply colored fruits and vegetables—those of the deepest green, red, purple, yellow and orange. These foods have the most vitamins and minerals, and the colorful pigments are believed to protect against diseases such as heart disease, cancer and diabetes.

Dark green vegetables, beans, sesame seeds, oats, tofu, almonds and salmon also help maintain strong bones. Those who consume large amounts of red meat have a higher incidence of heart attack and stroke than do those who consume whole grains, vegetables, fruit, fish and unsaturated fat such as olive and canola oil. Occasional servings of red meat should be 90 percent lean.

Studies show that exercise also increases life expectancy and contributes to a general sense of well-being. Along with proper diet, exercise helps reduce or postpone the occurrence of heart attack, angina, some forms of diabetes, osteoporosis and hypertension and possibly elevates the level of good cholesterol (HDL) and helps to prevent or delay cardiovascular disease, the leading cause of death in the United States.

Extensive research has shown that exercise also reduces anxiety, depression, tension, weight and the effects of stress, as well as increasing mental alertness. Exercise does not have to be rigorous. A 30-minute walk or swim three or four times a week is beneficial.

Again, it's never too late to start. Studies show that physically trained 70- and 80-year-olds outperform sedentary 30-year-olds.

Treating our bodies well is only part of the formula. Our social ties, attitudes and philosophies also influence our quality of life and longevity. Older people who have close relationships with family, friends or organizations have better health than those who are isolated or less socially involved. And there is a strong correlation between church or synagogue participation and low mortality risk. Pets can also be good medicine.

Behavior also affects longevity.

Anger tops the list of behavior that puts a person at risk for heart attack or stroke, especially if significant heart disease or heart risk factors already exist, such as high blood pressure, a poor cholesterol profile, diabetes or obesity. Medical authorities report that heart attacks are two to three times more likely and stroke twice as common in those with anger management issues. Frequent and extreme anger triggers potent stress factors, which may also provoke heart attack or stroke. Develop anger coping skills: deep breathing, meditation, yoga. Identify and avoid people or situations known to cause stress. Write about the situation or talk it over with someone who has a calming influence. Strive for optimism.

Have a good laugh. Mirthful laughter does much more good than we think, says local pathologist and popular speaker Dr. Josh Sickell. He tells his audiences, "The power of humor is at work thoughout life, consoling and healing. Humor reduces stress and anxiety, relieves pain, stimulates circulation, enhances immunity, bolsters morale and maintains hope."

What's the take home point? Review your resolutions for this year and for life. Longevity may lie in our own hands, and it's never too late to begin a new regimen. Remember these well-known words: "Care for your body as if you were going to live forever. Care for your soul as if you were going to die tomorrow."

Rita Baum has a master's degree in gerontology and has worked in the field of aging for more than 20 years.