Functional Age Vs Chronological Age

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A universal occurrence, aging involves changes in sensory, cognitive and motor skills as a response to advancement in age. But everyone does not age at the same rate.

As they grow older, some people may experience a very quick decline in their physiological, as well as psychological functioning, whereas, in others, the changes may be less noticeable over time.

So that brings us to the question, “what is the difference between chronological age and functional age?

Functional Age vs Chronological Age: What's The Difference?

Chronological Age

Chronological age is essentially the number of years that have elapsed from when you were born to the current date. It is your birth age or calendar age defined in years, months and days.

It refers to the amount of time that an individual has been alive and this remains constant and does not change. Chronological age is also a key risk factor for mortality, chronic diseases and diminishing the body functions such as hearing, vision, memory, etc.

Functional Age

Also known as biological or physiological age, functional aging differs from chronological age and is essentially a combination of physiological, social and psychological age.

The actual functional age is determined by various physiological and biological development factors including chronological age, genetics, nutrition, lifestyle, diseases, etc. It is also affected by external factors such as diet, stress, exercise, smoking, etc.

Your biological age may not be the same as your chronological age. For instance, if you’re a 30-year-old male who has been smoking a pack of cigarettes a day for around 10 years and consuming a high-fat diet and exhibiting signs or pre-diabetes, your biological age is most probably well over 30 years.

According to gerontologists, chronological age is not complete because it does not take into account all these external factors. The functional age of a person is determined by the functional capability of the person indexed by the standards for the age.

For example, a child’s functional age is measured by the developmental level he/she has reached. It can be compared to his/her chronological age as a way of determining the existence and extent of any development problem or impairment.

In adults, functional age is calculated by measuring many variables correlating with chronological age such as hearing, eyesight, cardiopulmonary function, memory, concentration and mobility.

In fact, the Age Discrimination in Employment Act has made using the functional age as a criterion for employment in certain jobs rather than the old system of chronological age.

How Functional Age Is Determined

As per research, DNA methylation and telomeres play very important roles in the aging process and it is possible to determine biological or functional age using these two.


These are essentially the nucleotides located on the ends of chromosomes, which aid them from weakening and getting fused with the chromosomes around. Telomeres influence the aging and dying of the cells in the body.

Research has found that older people with a higher chronological age have shorter telomeres compared to younger people.

A study discovered that people with shorter telomeres are more likely to die early, and develop a neurodegenerative disorder or some disease.

According to another study, following a healthy lifestyle can help to lengthen the telomeres and in turn, help to reverse aging.

DNA Methylation

Biological age can be determined by using DNA methylation, which is used by the cells in the body to control gene expression.

This essentially means that DNA methylation turns the genes off and is very important for various processes such as the development of the embryo, chromosome stability, genomic printing, etc.

A study was done to discover whether DNA methylation is a precise method of predicting the functional age by collecting 8,000 samples of 51 cells and tissues.

Most of the cell and tissue samples that were studied had the same chronological, as well as biological ages, while others did not. It was found that some parts of the body age more quickly compared to others.

For instance, the oldest tissue in the body is breast tissue. Healthy breast tissue can be 3 years older than the rest of the body and if the tissue is near any cancerous tissue, then it can be even 12 years older.

Tips To Age In A Healthy Way

There are many ways by which you can improve your functional age and here are some tips on how you can age healthily.


Engage in physical activity or exercise regularly. This is especially beneficial for people suffering from heart disease, diabetes, high blood pressure or arthritis.

It helps older adults to have improved heart and lung function, which in turn, helps to reduce fatigue and increase endurance.

exercise such as walking contributes to the "Functional Age vs Chronological Age" debate

Some of the best exercises include strength training, which helps to build bones and muscles and helps to reduce the risk of osteoporosis. Balance exercises can help to reduce the risk of falling in elders.

Endurance exercises such as walking, cycling and swimming can help to improve stamina, enhance heart and lung health and also boost circulation.

Stretching can help to loosen the muscles in your body and keep you flexible so that you can do all your daily activities easily minus the aches and pains.

Follow A Healthy Diet

There is a direct link between diet, nutrition and functional age. And, it is a good idea to follow a healthy diet. And, when shopping for food, make sure to choose healthy foods and check the nutrition labels. Doing this can help to reduce your biological age.

healthy diet contributes to the "Functional Age vs Chronological Age" debate

Eating Low GI Foods

Include more foods with low GI (glycemic index) value foods to your diet. Low glycemic foods such as whole grains, veggies, fruits, low-fat dairy and beans contain nutrients that help in keeping your organs, bones and muscles strong.

Avoid or reduce consuming junk food, white bread, sugary drinks, etc. These can increase your blood sugar.

Maintain A Healthy Weight

Being overweight is associated with several health risks including heart disease, diabetes, high blood pressure, cancers, etc. And, in turn, can lead to an increase in your biological age.

Maintain A Healthy Shape

Apart from your weight, to age healthily, it is important to determine how the fat is distributed in your body. The fat distribution is typically determined by the waist circumference and the waist-to-hip ratio of a person.

  • Apple-Shaped Body: In this shape, the fat gets to the waist and abdomen from the outer edges, increasing the risk of diseases like heart disease and breast cancer.
  • Pear-Shaped Body: Here, the fat accumulates in the other areas such as the thighs and hips, which is a sign of healthy distribution of fat.

Functional Age vs Chronological Age: Wrapping Up

In conclusion, chronological age is your birth age, which increases at a constant rate with the passing of years.

Functional age, also known as biological age, is determined by a combination of several factors. It is possible to reduce your biological age by making a few lifestyle changes and live a healthier and longer life.

I have had my functional age tested and although I am in my 60's, my functional age is over 10 years younger. I work on my health and lifestyle to try and continue to reduce my functional age even more.

Rosemary Richards