Metabolic age: What is it and what does it say about your health?

If you had a stage in your life when you could eat anything and not really gain any weight, you may wonder what happened along the way – and it all comes down to how efficiently your body can metabolise food and burn calories.

One term you may have heard about before is ‘metabolic age’. In short, it is a measure of your overall metabolic health and can provide insight into your risk for developing certain health conditions.

But is this actually a useful measuring tool? What exactly can it tell you and how should it be used? Let’s find out.

What does metabolic age mean?

In simple terms, your metabolic age tells you how efficiently your body burns calories and whether your metabolism is faster or slower than average for your age.

“We are still waiting for more peer-reviewed studies on its usefulness; however, having a greater understanding of how your metabolism works is helpful,” said Dr Kirsty Wallace-Hor, a specialist GP at Juniper.

“Your metabolism is the process by which your body converts calories (all the food and drink you consume) into the energy required for your body to function. People with faster metabolisms burn calories faster. A slower metabolism slows down the conversion of calories into energy, which can lead to more fat storage in the body.

“We know that metabolism changes as we age because our energy requirements and body composition change. A recent study showed that our total daily energy expenditure peaks at about one year of age, then declines to an ‘adult’ level at about 20 years, and then remains stable for decades before declining again after 60 years.

“We also tend to lose muscle and gain fat as we age, which slows down our metabolism because muscle requires more energy to operate than fat. Hormonal changes, as women approach menopause, also redistribute fat more centrally – which carries more health risks than subcutaneous fat.”

What does your metabolic age say about your health?

Your metabolic age can give you valuable insights about whether:

• Your body burns calories efficiently
• Your body fat percentage is high (and muscle mass is low)
• You’re at a higher risk of conditions like diabetes and heart disease
• You have good fitness levels and cardiovascular health
• You’re meeting your body’s nutritional needs
• You’re going through hormonal imbalances
• You need to make healthier lifestyle choices.

How to calculate your metabolic age

“The calculation of your metabolic age is based on your basal metabolic rate (BMR), which reflects the calories your body burns at rest,” Dr Wallace-Hor explains.

However, calculating your real metabolic age is a complex process, as you need access to specific data that can be difficult to access, like your body composition and resting blood pressure.

“Fortunately, there are other measures that can help determine the state of your metabolic health, such as waist circumference,” Dr Wallace-Hor explains.

“Discussing other metabolic risk factors, such as high blood pressure, smoking, high cholesterol and high blood sugar with your health professional is also important in terms of reducing your risk of developing conditions like heart disease, type 2 diabetes and some cancers.”

What to do if your metabolic age is too high

A good metabolic age should either match or be lower than your actual, chronological age. For example, if you’re 30 and your metabolic age is, say, 37 – that’s too high. So, what can you do to bring it back down?

“Measures that we know help improve your metabolic health include increasing your physical activity. Any activity can help, but high-intensity interval training, in particular, has been shown to improve your metabolic rate,” said Dr Wallace-Hor.

“Improving your sleep can influence metabolism, as can strength training, as this improves your muscle mass. Increasing your dietary intake of fibre, protein and healthy fats, and reducing processed foods and refined sugars are also important.”