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What Is Your RealAge?

We all know someone whose age is hard to believe, thanks to a youthful appearance. Do these people have a deal with the devil, or do they just know the secrets of lowering their biological age?

While your chronological age is fixed, your biological age may be years older or younger, depending on a combination of factors. Some of them are factors you can control.

RealAge is a system that lets you calculate the aging effects of more than 100 different health behaviors ranging from diet and medication to stress control and chronic smoking.

Dr. Michael Roizen, of the University of Chicago, wrote the book RealAge: Are You as Young as You Can Be? He and four other scientists developed a systematic program that calculates the aging effect of health behaviors. It also shows how to design a specific path toward improving or reversing your own aging trajectory.

The RealAge program uses a comprehensive questionnaire to determine your biological age. You can find out your RealAge by answering the questions on the RealAge Web site at

Questions cover nutrition, physical activity, environment, genetics and family history, and stress. Maintained by scientists at the University of Chicago, the site provides recommendations for each user based on his or her answers.

Here are some of the factors that determine your RealAge compared to your chronological age:

  • Smoking A person who smokes a pack a day is 4.9 years older. A person who doesn't is 2.1 years younger.
  • Exercise If a person does the right amount of exercise, he or she is 8.7 years younger.
  • Heredity If both parents lived past 75 years of age, a person is four years younger.
  • Sex People who have healthy, monogamous sexual relationships are 1.6 to 8 years younger than those who don't.
  • Dogs Owning a dog can make you one year younger. (They think this is because you have to go out and walk a dog.)

  • Dr. Roizen argues that genes are not the only factor in how we age. How you interact with the world around you, from your eating and exercise habits to your social behaviors, determines the way you genes will affect your body in terms of aging.

    So, if you're 40 years old and you did everything "right," your RealAge is 28.5 years.

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