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Biological vs chronological age

5 minute read
A group of people on the ground stretching out their legs in workout gear.

Most of us know what our chronological age is or how old we are in calendar years, although some of us prefer not to count how many candles are on the birthday cake each year.

We tend to attach a lot of importance to our chronological age. We say things like ‘we look good for our age’ and put pressure on ourselves to achieve certain milestones with the ‘big’ birthdays of 30, 40 and 50. Our parents or grandparents may have died by a certain age and we may link our own mortality to that number, even unconsciously.

But what if we’re focussing on the wrong set of numbers? What if our health depends not on our chronological age, but on our biological age?

Your biological age

Your biological age reflects your body’s current state of health. It’s a measure of risk factors for chronic disease that would put you in the same health bracket of someone with that chronological age.

So while your chronological age may be 50, if you exercise regularly, eat and sleep well, don’t smoke or drink to excess, your biological age may be closer to 40.

Likewise, we all know a guy who’s in his 20s, drinks alcohol, chain smokes, plays video games into the wee hours and whose vegetable intake is limited to the mushrooms on a supreme pizza! Though he may not look it (yet), his biological age might be 15 years older than his calendar age.

What impacts biological age?

Research published in the Plastic and Reconstructive Surgery journal looked at different sets of identical twins and how their lifestyle choices made subtle differences to how old they looked. Behaviours like smoking, sun exposure, weight and stress created the most visible signs of ageing – and these are just the signs you can see on the outside. Poor nutrition and lack of exercise can contribute to the more dangerous internal signs of aging, such as low bone density, cognitive decline, reduced lung capacity and heart disease.

An older woman walking with a young man after working out together.

Why is biological age important?

It’s tempting to think that if you don’t do anything extraordinarily bad for you (like the guy who ate only McDonald’s for thirty days) your biological and chronological ages will more or less match.

But this is not necessarily so.

Because the typical western diet is so high in saturated fat and sugar, and we are increasingly sedentary, most of us have a biological age a bit higher than our chronological age. In fact, researchers have found that four out of five people have an older ‘heart age’ than their chronological age.

Ready for some good news?

By making a few lifestyle changes, it’s entirely within your power to lower your biological age. And the earlier you intervene, the better off you are.

How can I lower my biological age?

1. Stay in a healthy weight range

Yes, BMI is not a perfect marker of health, but research shows that those within a healthy weight range for their height have a lower risk of heart disease, diabetes, high blood pressure and certain cancers.

Also, keep an eye on where you store weight. Your doctor might not be concerned about a few extra kilos around your hips and thighs, however there’s a strong correlation between heart disease and extra weight around the mid-section – so watch that tummy!

2. Exercise

Weights: Resistance training is one of the most important things you can do to prevent osteoporosis. And because we lose bone density as we age, we need to weight train just to avoid losing the muscle we already have.

Cardio: Researchers at Brigham Young University found that 40 minutes of cardio, five days a week will cut your biological age by nine years. Not only will it boost heart and lung health and keep diabetes in check, it will also slow down mental decline.

In fact, neuroscientists say forget brain training – cardiovascular exercise is the best thing you can do to improve memory and decrease the risk of dementia.

Stretching: By maintaining your full range of motion, you’ll ensure not only a longer life but a more active, mobile and enjoyable one.

Two women in a public swimming pool wearing swimming caps

3. Nutrition

Adopting a style of eating similar to the Mediterranean Diet will help keep heart disease and diabetes at bay. This way of eating incorporates low GI grains and legumes, lean meat, the Omega 3 ‘good fats’ found in oil, avocado, fish and nuts, and antioxidant-rich food like dark, leafy greens.

Avoid refined carbohydrates (looking at you, sneaky mid-morning bagel) and high-fat/sugar foods which contribute to weight around the middle.

4. Sleep

Ideally, seven to eight hours a night. Sleep triggers your parasympathetic nervous system to go into ‘rest and repair’ mode. Our body repairs itself physically during the initial phase of sleep, and then mentally. So while you may be able to get by on less, your mental health and ability to manage stress will suffer. Sleep deprivation has been linked to heart disease and type 2 diabetes, and a US study found that those who routinely slept less than five hours a night had a biological age five years greater than their chronological age.

5. Stop

Sitting: Even if you exercise, researchers at the University of California found that women who sat for around ten hours a day (think work, plus commute, plus screen time) increased their biological age by eight years. Aim to get up every hour to increase circulation and take a walk around the block or the office floor.

Smoking and alcohol: Research published in the Journal of Epidemiology & Community Health found that heavy drinking and smoking adds years to your biological age.

6. Stress

Prolonged exposure to stress has been proven to shorten lifespans. Whether it’s working out, journaling, making time to socialise or scheduling more ‘me time’ during periods of stress, giving yourself space to decompress could add years to your life in the long term.

And take heart. Any kind of lifestyle change, even a positive one, takes work and initial discomfort. But by sticking with it, you’ll not only live longer, you’ll thrive.

Keen to improve your health? Check out the health tips page of The Check Up.

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