Consider this: In the 20th century, the average life expectancy shot up 30 years--the greatest gain in 5,000 years of human history. And this: Centenarians -- folks who make it into the triple digits -- aren't such an exclusive club anymore, increasing 51% from 1990 to 2000. How to account for these dramatic leaps? Advances in health, education, and disease prevention and treatments are high on the list--and that makes sense. But what you may not know is that seemingly unimportant everyday habits, or circumstances in your past, can influence how long and how well you'll live. Here, the latest research on longevity--science-based signs you're on a long-life path, plus tips on how to get on track.
Sign: Your Mom Had You Young
If she was under age 25, you're twice as likely to live to 100 as someone born to an older mom, according to University of Chicago scientists. They suspect that younger moms' best eggs go first to fertilization, thus healthier offspring.
Sign: You're a Tea Lover
Both green and black teas contain a concentrated dose of catechins, substances that help blood vessels relax and protect your heart. In a study of more than 40,500 Japanese men and women, those who drank 5 or more cups of green tea every day had the lowest risk of dying from heart disease and stroke. Other studies involving black tea showed similar results.
You really need only 1 or 2 cups of tea daily to start doing your heart some good--just make sure it's a fresh brew. Ready-to-drink teas (the kind you find in the supermarket beverage section) don't offer the same health benefits. "Once water is added to tea leaves, their catechins degrade within a few days," says Jeffrey Blumberg, PhD, a professor of nutrition science and policy at Tufts University. Also, some studies show that adding milk may eliminate tea's protective effects on the cardiovascular system, so stick to just lemon or honey.
Sign: You'd Rather Walk
"Fit" people--defined as those who walk for about 30 minutes a day--are more likely to live longer than those who walk less, regardless of how much body fat they have, according to a recent study of 2,603 men and women. Similarly, overweight women can improve their heart health by adding just 10 minutes of activity to their daily routine, says recent research. So take a walk on your lunch hour, do laps around the field while your kid is at soccer practice--find ways to move a little more, every day.
Sign: You Skip Soda (Even Diet)
Scientists in Boston found that drinking one or more regular or diet colas every day doubles your risk of metabolic syndrome--a cluster of conditions, including high blood pressure, elevated insulin levels, and excess fat around the waist, that increase your chance of heart disease and diabetes. One culprit could be the additive that gives soda its caramel color, which upped the risk of metabolic syndrome in animal studies. Scientists also speculate that soda drinkers regularly expose their tastebuds to natural or artificial sweeteners, conditioning themselves to prefer and crave sweeter foods, which may lead to weight gain, says Vasan S. Ramachandran, MD, a professor of medicine at Boston University School of Medicine and the study's lead researcher. Better choices: Switch to tea if you need a caffeine hit. If it's fizz you're after, try sparkling water with a splash of juice. By controlling blood pressure and cholesterol levels, preventing diabetes, and not smoking, you can add 6 to 9 1/2 healthy years to your life.
Sign: You Have Strong Legs
Lower-body strength translates into good balance, flexibility, and endurance. As you get older, those attributes are key to reducing your risk of falls and injuries--particularly hip fractures, which often quickly lead to declining health. Up to 20% of hip-fracture patients die within 1 year because of complications from the trauma. "Having weak thigh muscles is the number one predictor of frailty in old age," says Robert Butler, MD, president of the International Longevity Center–USA in New York City. To strengthen them, target your quads with the "phantom chair" move, says Joan Price, author of The Anytime, Anywhere Exercise Book. Here's how: Stand with back against wall. Slowly walk feet out and slide back down until you're in a seated position, ensuring knees aren't beyond toes and lower back is pressed against wall. Hold until your thighs tell you, Enough! Do this daily, increasing your hold by a few seconds each time.
Sign: You Eat Purple Food
Concord grapes, blueberries, red wine: They all get that deep, rich color from polyphenols--compounds that reduce heart disease risk and may also protect against Alzheimer's disease, according to the new research. Polyphenols help keep blood vessels and arteries flexible and healthy. "What's good for your coronary arteries is also good for your brain's blood vessels," says Robert Krikorian, PhD, director of the Cognitive Disorders Center at the University of Cincinnati. Preliminary animal studies suggest that adding dark grapes to your diet may improve brain function. What's more, in a recent human study, researchers found that eating 1 or more cups of blueberries every day may improve communication between brain cells, enhancing your memory.
Sign: You Were a Healthy-Weight Teen
A study in the Journal of Pediatrics that followed 137 African Americans from birth to age 28 found that being overweight at age 14 increases your risk of developing type 2 diabetes in adulthood. Adults with diabetes are two to four times more likely to develop heart disease than those without the condition, according to the American Heart Association.
Sign: You Don't Like Burgers
A few palm-size servings (about 2 1/2 ounces) of beef, pork, or lamb now and then is no big deal, but eating more than 18 ounces of red meat per week ups your risk of colorectal cancer--the third most common type, according to a major report by the American Institute for Cancer Research. Colorectal cancer risk also rises by 42% with every 3 1/2-ounce serving of processed meat (such as hot dogs, bacon, and deli meats) eaten per day, the report determined. Experts aren't sure why red and processed meats are so harmful, but one of their suspects is the carcinogens that can form when meat is grilled, smoked, or cured--or when preservatives, such as nitrates, are added. "You can have an occasional hot dog at a baseball game, but just don't make it a habit," says Karen Collins, RD, a nutrition advisor at AICR. And when you do grill red meat, marinate it first, keep pieces small (kebab-size), and flip them often--all of which can help prevent carcinogens from forming. If you're baking or roasting it, keep the oven temp under 400°F.
Sign: You've Been a College Freshman
A recent Harvard Medical School study found that people with more than 12 years of formal education (even if it's only 1 year of college) live 18 months longer than those with fewer years of schooling. Why? The more education you have, the less likely you are to smoke. In fact, only about 10% of adults with an undergraduate degree smoke, compared with 35% of those with a high school education or less, according to the CDC.
Sign: You Really Like Your Friends…
"Good interpersonal relationships act as a buffer against stress," says Micah Sadigh, PhD, an associate professor of psychology at Cedar Crest College. Knowing you have people who support you keeps you healthy, mentally and physically: Chronic stress weakens the immune system and ages cells faster, ultimately shortening life span by 4 to 8 years, according to one study. Not just any person will do, however. "You need friends you can talk to without being judged or criticized," says Sadigh.
Sign: …and They're Healthy
If your closest friends gain weight, your chance of doing the same could increase by 57%, according to a study in the New England of Journal of Medicine. "To maintain a healthy lifestyle, it's important to associate with people who have similar goals," says Nicholas A. Christakis, MD, PhD, the study's lead researcher. Join a weight loss group, or train with a pal for a charity walk.
Sign: You Embrace the Challenge
People who consider themselves self-disciplined, organized achievers live longer and have up to an 89% lower risk of developing Alzheimer's than the less conscientious, according to two studies. When you're good at focusing your attention, you use more brainpower, says the lead researcher in both studies, Robert S. Wilson, PhD, a professor of neurological sciences and psychology at Rush University Medical Center in Chicago. Set personal or career goals, and challenge yourself to meet them by a certain time. Also, try new things to stimulate your brain: If you always read fiction, pick up an autobiography instead. The next day, try to recall three facts you learned from the reading.
Sign: You Don't Have a Housekeeper
Just by vacuuming, mopping floors, or washing windows for a little more than an hour, the average person can burn about 285 calories, lowering risk of death by 30%, according to a study of 302 adults in their 70s and 80s.
Sign: You're a Flourisher
About 17% of Americans are flourishers, says a study in American Psychologist. They have a positive outlook on life, a sense of purpose and community, and are healthier than "languishers"--about 10% of adults who don't feel good about them selves. Most of us fall somewhere in between. "We should strive to flourish, to find meaning in our lives," says Corey Keyes, PhD, a professor of sociology at Emory University. "In Sardinia and Okinawa, where people live the longest, hard work is important, but not more so than spending time with family, nurturing spirituality, and doing for others."