Key Health Factors Reveal Your 'True' Age

Was this helpful?
African american mother and daughter jogging together against blue sky

The expression “age is just a number” could be even more true than previously thought. In fact, there are reasons why some people feel younger than their ages while others feel older. A study published in 2015 found that biomarkers, some of which might reflect negative lifestyle habits, can be measured and can reflect the rate at which your body biologically ages. For some people, these factors might make them feel older than their chronological age and more prone to illnesses in their later years. 

Researchers followed 954 young adults in New Zealand for 12 years, from age 26 to age 38, to compare how they aged. They looked at key health factors that contribute to how the body ages and the long-term diseases that tend to accelerate the process.

Key health factors included:

  • DNA health (the aging of genes inside cells)

  • Good cholesterol levels

  • Heart and blood vessel health

  • Immune system health (the body’s defense system)

  • Kidney function

  • Lung function

  • Oral health (gum disease)

Biological vs. Chronological Age

By age 38, differences in aging were apparent, showing some people to be biologically older than their years. Though most hadn't yet developed any long-term diseases, they were at increased risk for problems like heart disease and stroke, and for fewer years of good health—what the researchers call having a shorter healthspan.

People who were biologically older:

  • Had lower physical ability including poorer balance and less strength

  • Reported that they felt less healthy

  • Looked older than their age, according to others

  • Had a faster decline in mental abilities including lower IQ scores

The researchers concluded that if patients can measure their biological age before chronic disease has developed, they can take steps to prevent those conditions.

Measuring Age

A 2018 study looked at American adults in the National Health and Nutrition Examination Surveys (NHANES). Researchers first used data from 10,000 adults between the years 1988 to 1994. They identified nine biomarkers that predicted life expectancy from this group. Then, they came up with what they call a phenotypic age. It’s a calculation using the biomarkers plus chronological age. It reflects a person’s biological or physiological age. Doctors can measure the biomarkers with a blood test.

Researchers then took their calculation and applied it to a second NHANES study. This time it included 11,000 adults from the years 1999 to 2010. They found that women tend to age more slowly than men. They also found that people with a higher phenotypic age had a higher risk of dying. For each year phenotypic age was greater than biologic age, the risk of dying increased as follows:

  • 14% for 20 to 39 year olds

  • 10% for 40 to 64 year olds

  • 8% for 65 to 84 year olds

So, a 65-year old adult with a phenotypic age of 70 has a 40% higher risk of death (70 y – 65 y = 5 years; 5 x 8% = 40%) than a typical 65-year old. What’s more, they found phenotypic age could predict disease-specific mortality including:

Researchers also found people who age faster have more diseases across all age groups. This makes sense. However, they were even able to pick up differences in seemingly healthy people. And this is what makes their calculation of phenotypic age intriguing. It might provide a tool doctors can use to spot potential problems before any signs of disease.
If you are at high risk for chronic diseases, such as diabetes, doctors might also use this tool. By plugging in your numbers, your doctor can show you how changing lifestyle or risk factors will affect your risk of dying. For example, you can see how lowering your blood glucose (one of the markers) to a certain number will affect your life expectancy.

Take Action Today

Practicing a healthy lifestyle in your teens and 20s provides the most far-reaching benefit in terms of “slowing down the clock” and preventing chronic disease later in life. But regardless of how many birthdays you’ve celebrated, it’s never too late to start making healthier choices.

Here's how:

  • Maintain a healthy weight. Make sure your body mass index (BMI) is in a healthy range. You can calculate your BMI at the National Institute of Health’s website.

  • Eat a healthy diet. That means lots of fruits, vegetables, whole grains, and proteins from nutritious sources like lean meats, seafood, nuts and beans. Avoid sugar-added drinks and desserts; refined grains, such as white bread and pastas; and fats that are solid at room temperature, like butter.

  • Don’t add salt to your food. Sodium increases blood pressure, which makes your heart work harder.

  • Exercise most days of the week, for a minimum of 2 1/2 hours weekly. Do strength training at least twice per week.

  • Don’t smoke, and avoid secondhand smoke. If you do smoke, quit.

  • Don’t abuse drugs, and limit alcohol (1 to 2 drinks per day for men and 1 drink per day for women).

  • See your dentist regularly, floss once a day, and brush twice daily.

  • To prevent mental decline, stay active mentally: learn a new skill, start a new hobby or read a challenging book. Staying socially active also helps prevent mental decline.

  • Along with lifestyle changes, see your primary care provider regularly to get all recommended vaccinations and screening exams. Talk to relatives about your family health history to see if you’re at increased risk for any chronic illnesses. This way, you can take specific preventive steps now.

There may be no such thing as a fountain of youth, but with these healthy habits, you can improve your healthspan and keep your body feeling younger throughout all the years of your life.  

Was this helpful?
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Oct 7
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Belsky DW, Caspi A, Houts R, et al. Quantification of
    biological aging in young adults. Proc Natl Acad Sci U S A. 2015 Jul
  2. Health Tips for Adults. National Institute of Diabetes and
    Digestive and Kidney Diseases.
  3. Healthy Mouth, Adults Under 40. American Dental Association.
  4. How Can I keep My Lungs Healthy? Public Health Agency of
  5. Liu Za, Kuo PL, Horvath, et al. Phenotypic age: a novel
    signature of mortality and morbidity risk. bioRxiv Preprint Server.
  6. Preventive Health Care. Centers for Disease Control and
  7. Stay Mentally and Socially Active. Alzheimer’s Association. 
  8. Tips for a Healthy Liver. Canadian Liver Foundation.
  9. Tips for Healthy Living. American Kidney Fund.