Diet for a Lifetime

You know the healthy-food drill: Eat less fat; get more fruits and vegetables; and under no circumstances forget your fiber! These are a few of the dietary rules that doctors say can keep us healthy and happy for life.

But while those are great guidelines, the truth is that our bodies are works in progress. New health needs -- and certain health risks -- appear during each decade of our lives. And that means our nutritional requirements change over time as well.

"It's not that we don't need the same healthy habits at 20 that we do at 40; it's just that as we age, the need can become more critical," says nutritionist Samantha Heller, RD, a senior clinical dietitian with New York University Medical Center.

And as we move through each decade, the impact of unhealthy eating also becomes greater, says nutrition expert Nancy Wellman, PhD.

"You will start seeing some physical results that can become very apparent as you age," says Wellman, director of the National Resource Center on Nutrition, Physical Activity, and Aging at Florida International University.

To help you get optimal good health out of each decade of your life, WebMD asked three experts to help chart a lifetime of nutritional needs.

Your 20s and 30s

If there's a time that personifies health and vitality, it's the 20s and 30s. But just because you feel great and your energy knows no bounds, don't make the mistake of throwing dietary caution to the wind.

Even if you're "young and thin and go to the gym regularly, what you eat still matters because it has a chemical effect internally -- and that occurs regardless of your age," says Heller.

While you might not see or feel the consequences right away, Heller tells WebMD that over time, certain foods can increase your risk for serious diseases.

Indeed, research recently published in the American Journal of Clinical Nutrition revealed that the more red meat women ate between the ages of 18 and 30, the higher their risk for high blood pressure later in life.

The good news: The study also found that those who eat lots of fruits and vegetables reduce their risk of high blood pressure for years to come.

But it's not just your diet's effect on your future that matters. Nutritionist Jo-Anne Rizzotto, RD, says women need certain nutrients while they are in their 20s and 30s. Among the most important, she says, are calcium and vitamin D.

"Many young women associate these nutrients with adolescence, or with the postmenopause years," says Rizzotto, a dietitian and educator at the Joslin Clinic in Boston. "But the truth is, bone is still being laid down throughout your 20s. And without adequate calcium and vitamin D, your skeleton will not be as strong as you need it to be, now or in the future."