Calculating RealAge


How old are you now? How young could you be? Learn how to calculate your RealAge. You can do it either by using the charts provided in this book, which will give you a good approximation of your RealAge, or by going on-line to the RealAge Web site and calculating your biologic age more accurately using the RealAge computer database. By answering easy questions about 125 health factors, habits, and behaviors, you can determine whether you are ageing more quickly or more slowly than your contemporaries. Once you know your RealAge, you will have the information you need to start getting younger. By choosing from the recommendations in this book or in your computer printout, you can develop a step-by-step Age Reduction Plan customized to your needs and lifestyle.

Now that you understand the principle of RealAge—that you can get younger—you may be wondering how you can calculate a number that accurately describes your 'true' physiologic age. How can I say that some people are

[The RealAge effects specified in all chapters other than this chapter calculate the effects of the factor being considered individually. Let's take the example of blood pressure. Many factors contribute to your blood pressure reading, such as sodium intake and potassium levels, so that some of the effects attributed to blood pressure are attributable to other things as well. For example, exercise lowers blood pressure: three of the twelve years difference in RealAge between a fifty-year-old man who has the ideal blood pressure...  and one who has a high blood pressure...  is attributable to the stamina exercise component. The changes in RealAge described in all chapters except this chapter do not take into account the covariance or interaction between factors. Please refer to the tables in this chapter or the RealAge Web site at]


younger and others are older when their calendar ages are the same? People are so different from each other. For all those who get cancer from smoking, there is always one diehard who has smoked a pack a day since he was twelve and is going strong at ninety. So, how can I say that quitting a pack-a-day smoking habit will make you seven years younger? Or that taking an aspirin a day can make you not fifty-five, but fifty-three and a half?

For a long time, researchers saw ageing as a linear and roughly equal process. Most researchers considered all seventy-year-olds to be the same. This assumption was good for census bureau statisticians, but made for an inaccurate representation of reality. When you look at the population, it is apparent that all seventy-years-olds are not alike. Many are mobile, full of life, and living as young as fifty-year-olds. Others are homebound, bedridden, or suffering from a wide range of health complications. Not everyone ages equally.


The Nuts and Bolts of RealAge: The Science Behind the Numbers

If you chart the health, longevity, and, ultimately, youth of a 'population age cohort,' a group of people all born in the same year, you will find that with few exceptions, people age at a similar rate until they reach their late twenties or mid-thirties. With the exception of those who have inherited rare genetic disorders or have been in serious accidents, everyone is basically healthy and able. Men reach the peak of their performance curve in their late twenties, and women, in their mid-thirties. Our bodies have fully matured, and we are at our strongest and most mentally acute. Then, somewhere between twenty-eight and thirty-six years of age, most people reach a turning point—a transition from 'growing' into 'ageing.'

If you examine the population as a whole and track any one biologic function—whether kidney function or cognitive ability—performance declines as we age. In general, each biologic function decreases 3-6 percent per decade after age thirty-five. That decrease is a measure of the average for the population as a whole. Although these types of measurements have been the standards used by scientists to calculate the rate of ageing, these averages don't take into account the variation among individuals. For older populations, the variation is so great that it is often meaningless to calculate an average at all because averages are statistically meaningful only if the people or things being measured actually congregate around a midpoint. With ageing, this does not happen. In fact, if you really look at the numbers, there is so much variation among individuals that the 'average' obscures more than it shows. Rather than gathering around a mean (the center), there are people in every age group who fit into every category of function— some showing dramatic decline, others showing virtually none.

The variations in the ability to function cover the entire range of possibility. For every seventy-year-old who's debilitated from cardiovascular disease, there's another who's running road races or traveling the globe. You can see this variation. If a horizontal line were drawn across the three lines representing the rapid, average, and slow rates of ageing, you would find that people of different calendar ages fall at the same place on the curve representing ageing.

In fact, for certain functions, such as mental acuity and IQ, some people show almost no decline and even improve as they progress from calendar age thirty-five to seventy-five. The question is how can you be one of those people who stay at the top of the curve, as young at seventy-five as you were at thirty-five? And that means not just living longer, but living better, suffering less illness and disability. Studies have repeatedly shown that making your RealAge younger means that you live longer and healthier.

To understand how the numbers work, consider a real-life example—the impact of smoking on life expectancy. Statistics show that the average life expectancy is seventy-seven years for men and eighty-three years for women. These numbers include everyone who dies prematurely from smoking. If you eliminate the data for smokers from the data for the general population, life expectancy goes up substantially. Thus, we can say that smokers have shorter lives and more medical problems than nonsmokers. We can also say that non-smokers have longer lives. In our equations, the RealAge team calculate a person's RealAge with respect to smoking by contrasting the ten-year survival rate, a calculation of life expectancy, of the smoker to that of the nonsmoker. By calculating the degree of risk and prorating it to the average ten-year survival rate for that person's chronologic age group, we found the number of years that smoking can subtract from one's life and that not smoking can add to one's life. We apply this process to a whole range of behaviors and conditions, using a complex routine of statistical techniques to blend them and arrive at a number that reflects your biologic age.

A fifty-two-year-old woman who smokes twenty-four cigarettes a day has an 88 percent probability of living for the next ten years. Likewise, the sixty-year-old woman who doesn't smoke also has an 88 percent probability of living ten years. Although eight calendar years separate these two individuals, their risk of dying within the next ten years is exactly the same: 12 percent. In other words, the smoker is the same physiologic 'age' as the nonsmoker who is eight calendar years older. RealAge is a calculation of your relative risk of dying versus that of the population as a whole, based on the law of averages. If your relative risk matches that of the average person who is ten years younger, that is the same thing as saying that your RealAge is ten years younger. You are at the same risk of suffering severe ageing or a major health problem as someone that much younger. Physiologically, you are equal.

This risk-analysis calculation is the clearest measure we have for determining the rate at which you are ageing. We draw data from clinical studies calculating the risk of death for a variety of factors and integrate them into survival-table analyses (Kaplan-Meier curves). We have derived these curves to evaluate individual conditions, habits, and other factors that tend to affect physiologic age. Our computer-based equations use the most up-to-date and reliable medical information available, which is then modeled by statisticians using the best and most subtle statistical formulations for multivariate equations.

In our calculations, we start with the most general statistic: average life expectancy for American men and women. We then break each category into smaller and smaller categories. For example, we consider weight-to-height ratios.

We calculate the long-term effects of smoking. We evaluate the benefit that people get from taking aspirin regularly, exercising, or managing health problems effectively. Each breakdown allows us to refine our measurement and to consider how much of an impact each action has on the ageing process. Finally, we consider all these categories together, calculating a multivariable equation in which we are able to weigh these multiple and diverse factors together and develop a unique RealAge calculation especially tailored to each person. We integrate the risk calculations for 125 factors and arrive at a number uniquely descriptive of you.

Sounds complicated? It is. But don't worry. To participate, all you have to do is answer a set of questions that allows us to calculate your RealAge. We do the rest.

The Studies That Provide the Data: Where Do the Numbers Come From?

RealAge is an information system. Instead of providing new scientific data, it is a way of reinterpreting already published results. We use data from the most up-to-date studies done by the leaders in each field of medical research, so you are getting the best information the medical community has to offer. What we do is unify all that information: We are able to integrate specific recommendations from hundreds of studies into a general framework, so you can understand how the recommendations relate to you. Whereas most medical researchers have calculated their statistics in relation to 'risk of disease,' we have used then-data and recalculated them to determine 'risk of ageing.' RealAge translates currendy available research into information you can use—something you can integrate into your own life.

I, in conjunction with the four other medical experts who form the RealAge scientific advisory team, have pored over more than 25,000 medical studies, evaluating what they tell us about ageing, and, more important, what they tell us about the prevention of ageing. Our calculations are based on data from more than 800 of the 25,000 studies and have been checked against a very large proprietary database. Our formulas are constantly being updated as new research becomes available. As statistics relating to these and other factors change, we recalculate our equations to accommodate the change. (Our on-line computerized RealAge program is updated whenever new and important research appears. For example, because Americans are becoming progressively heavier, we have modified our weight-to-height ratios to reflect these expanding waistlines.)

Although my colleagues and I rely on all kinds of scientific information for our calculations, let me describe our major sources of data. We predominately use clinical studies of two types: large-scale, risk-factor epidemiology studies and smaller-scale randomized trials. The large-scale studies look at many people, sometimes more than 100,000 individuals, and in one instance (the Mr. FIT study), as many as 350,000. The researchers who coordinate these studies track huge populations for a certain period, looking at one behavior or testable factor, such as blood pressure, and evaluate risks associated with that behavior or factor. These studies give statistics for a large population, more accurately reflecting variations within the study sample. The drawback is that these studies do not provide very detailed information and are not controlled studies. The researchers are not able to regulate with any kind of reliability who takes a specific drug or engages in a specific behavior. That is why scientists also do smaller controlled studies. In a randomized controlled study, a study population of a few hundred to 10,000 people is randomly divided, and each group is assigned a certain task. For example, half the group may be told to take the vitamin folic acid and half may be told to take placebos (harmless sugar pills). Each participant is then tracked for a long period, and his or her health conditions are recorded. At the end of the study, the researchers compare the groups and evaluate the effect of a particular behavior or condition on the overall health of the groups.

We select only factors that have been shown to make a quantifiable difference in the profile of risk (in other words, ageing) in at least three peer-reviewed studies. We integrate and compare the various studies that have pertained to a certain isstie; calculate what each study tells us about ageing; and, finally, come up with a RealAge number that tells you in one easy-to-under-stand number—years—what the impact of each behavior is on you.

What's Your RealAge?

There are two ways you can estimate your RealAge: by taking the RealAge survey on computer or by using the charts included in this chapter. The computer program is customized to you, whereas the charts provide accurate but more general approximations of your RealAge. In the RealAge questionnaire—both the one offered here and the on-line version—we ask you detailed questions about a variety of behaviors that are known to relate to ageing. What do you eat? How often do you exercise? Do you floss your teeth? Do you own a dog? How many close relationships do you have? How long did your parents live? Indeed, we ask you questions about 125 factors that affect your health and your youth. Your answers to these questions are the raw data needed to calculate your RealAge.