How old are you really?

by | Mar 22, 2023

Key takeaways

  • Your chronological age is the number of years you've been alive. Your biological age is a reflection of how old your body is and is influenced by various internal and external factors, including genetics, lifestyle, and environmental factors
  • Biological age can be measured through laboratory tests, and your pace of aging can be faster or slower than your chronological age
  • To slow down the pace of aging, focus on the four pillars of health: diet, exercise, sleep, and stress management

I recently had the honour of celebrating 50 years of travelling around the sun on our beautiful little blue planet, 50 years of living life and experiencing all that it has to offer. I recall my nanna telling me on my 21st birthday “You’ll be 30 before you know it”. Well, nanna, you were right. With my 30’s and 40’s now behind me, I find myself on the precipice of embracing my 50’s.

After the celebrations died down, and Christmas and New Year passed by, I took a moment for some quiet reflection, and asked myself one simple question – how old am I really?

Well thanks to some great advances in the science of ageing and a handy little online calculator I came across, it turns out that I’m only 42! How is that you ask? In this article, I’m going to explain the difference between your chronological age and your biological age. I’ll discuss some of the factors that influence your biological age and give you some simple strategies that you can start using today to improve your biological age and maybe even wind back the hands of time.

So, let’s look at the difference between your chronological age and your biological age.

Chronological age vs biological age

What is your chronological age?

Your chronological age is quite simply the number of years you have been alive since your birth.

It’s a linear fact that as time goes by, you age chronologically.

Unfortunately, there is nothing you can do about your chronological age, it is simply a measure of time.

What is your biological age?


Your biological age is a more accurate reflection of how old your body is, which I find much more interesting. This is based on your physiology, or how your body works which is why sometimes biological age is referred to as physiological age.

Biological age is influenced by a number of internal and external factors, including:


  • your genetic inheritance
  • your predisposition to developing chronic disease (often determined by your family history and other risk factors)
  • your gene expression (remembering that just because you have the gene, doesn’t mean you have the problem)
  • epigenetic influences from the environment
  • your social situation
  • your experiences during life
  • as well as the mainstays of diet, exercise, lifestyle, sleep, and stress management

Whilst this might seem like an overwhelming list of factors, the good news is, you have personal control over many, if not most, of these things.

Without delving too much into the science, it is worth noting that biological age has two main factors:

Our actual biological age (determined by your physiology) – this can be tested using several different laboratory measures such as methylation profiles or telomere length.

Your pace of ageing – or simply put, whether you’re ageing faster or slower than your chronological age. Let’s say you are 50 years old chronologically, but your biological age is 42, this means that your body is ageing more slowly than your chronological age, in this case for every one year (365 days) that goes by, you only biologically age 0.84 years (307 days). Of course, the reverse is also true, that if your biological age is higher than your chronological age, then your body is physiologically ageing faster.


How can we slow down the pace of ageing?


There are a number of things we can do to positively influence our biological age, and slow down the pace of ageing, starting with the basics.


Slowing ageing by addressing the 4 pillars of health


At Melbourne Functional Medicine there are four things that we believe matter most to human health.

These 4 ‘pillars’ are known as eat, move, sleep and stress.

Here are my top tips to optimise your health, and slow down the ageing process, using the pillars of health:


1. Eat

  • Consume a health-promoting diet every day. Start with eating a wholefood diet that is abundant in fresh fruits and vegetables, lean quality proteins, good quality fats, low in processed foods, and free from foods that you are allergic or sensitive to
  • Remember to eat the rainbow and pack plenty of colour into every meal
  • Include foods that are rich in B12 (meat, fish, some fermented foods), choline (eggs, legumes, cruciferous vegetables), betaine (beets, broccoli, ancient grains), and folate (dark green leafy vegetables, beans, sunflower seeds)
  • Drink plenty of clean, filtered water to stay well hydrated. Your urine should be almost clear, if it’s not, drink more water
  • Consider some form of regular fasting if it’s right for you

2. Move

  • Engage in regular exercise that gets the heart rate up, induces sweating, and makes you breathe harder. If you’re not used to exercising or you have a condition that prevents you from exercising consult your health or fitness professional for advice
  • Include strength or resistance training regularly and don’t forget about flexibility
  • Break up long periods of sitting by getting up and moving around for a few minutes every 20-30 mins, and if you work at a desk all day consider getting a sit-stand desk so you regularly move between sitting and standing

3. Sleep

  • Establish a healthy sleep routine by going to bed at a regular time each night
  • Try to get 6-8 hours of good quality sleep depending on your individual needs
  • Pay attention to sleep hygiene by reducing screen time before bed, don’t overheat in bed, and keep the room well-ventilated if possible

4. Stress

  • Remember it’s OK to have a slow day. You don’t need to push yourself all the time. Chill out, listen to music, watch a good comedy, read, or engage with your favourite hobby
  • Practice breathing techniques regularly throughout the day. Taking 2-3 controlled deep breaths 4-6 times a day helps to turn down the physiological stress response
  • Consider a daily mindfulness or meditation practice. Just 10-15 mins a day can significantly improve your stress response and stress resilience

So, how old are you really? We now know that while our chronological age is fixed, our biological age is much more malleable, and we can take action to improve it.

By focusing on the four pillars of health – eating well, moving regularly, getting enough quality sleep, and managing stress – we can positively influence our biological age and slow down the pace of ageing.

It’s never too late to start making changes and investing in our health, and with the right approach, we can feel younger and more vibrant than ever before.

Mark Payne

Mark has 30 years of experience as a clinical health professional, and has a particular interest in health optimisation and longevity, as well as cardiometabolic health, digestive disorders, and immune disorders.