Like so many other things in the body, metabolism undergoes some serious changes as we get older. Don’t panic! It’s normal, manageable and totally not the end of the world. All you need is just a little understanding of what your metabolism is and what happens to it over time.

So what is your metabolism? Here’s a quick run-down so that we’re all on the same page:


What is metabolism?

Metabolism is defined as the series of chemical reactions in a living organism that create and break down energy necessary for life. More simply, it’s the rate at which your body expends energy or burns calories.

Our bodies burn calories in several ways:

  • Through the energy required to keep the body functioning at rest
  • Through everyday activities
  • Through exercise

Other factors that determine how many calories your body burns each day include:

So how does this process change as we get older, and what does that mean for our bodies?


Your metabolism in your 20s

Typically, your metabolism through your mid-20s should be about the same as your late teenage years. With growth and muscle development, you have more cells actively burning calories. Note: the more muscle mass and less metabolically active fat you have, the more calories you burn in a day. Plus, your body continues to build bone until the age of 25, and this requires additional energy.

As you approach your late 20s, you may start to notice that the way you eat and exercise changes your energy levels. In fact, by your late 20s, you may actually undergo up to a 2% decrease in metabolic activity.

The reason for this? Even this early in life, we start to lose fat-free mass and gain incremental amounts of that less metabolically active fat. This means we have fewer cells burning fat as efficiently as before, so the rate at which we utilise food energy decreases while the rate at which we store it increases.

To combat this, here are some quick tips for you:

  1. Choose nutrient-rich foods that add value to your body.

Cut down on red meat and junk food and boost your intake of wholegrains. Eating a plant-based diet is one of the best ways to fill up on fewer calories: Fruits and veggies supply fibre and reduce your risk age-related diseases.

  1. Work strength and resistance training into your workout routines

Strength training helps to offset the effect of a sedentary job and maximises your body’s natural calorie-burning power by building muscle. If you do not have the time to workout at gym, why not take the stairs instead of the elevator whenever possible?


Your metabolism in your 30s

The human body will start to reduce muscle mass around the age of 35. Because body composition plays such an important role in how quickly and efficiently the body uses energy, the decrease in muscle mass prevalent during the mid-30s years can noticeably change your metabolism. With less muscle and more fat comes the sad truth that the body requires fewer calories to maintain the same weight.

According to experts, when you don’t use muscular strength, you’re effectively telling your body you don’t need to use those cells to burn energy. So, the body will store that potential energy as fat instead.

Also, by the time you’re in your 30s, you’re no longer producing the levels of Human Growth Hormone (HGH) you were in your 20s, which further decreases metabolism.

Good news, you can still make up for it by:

  1. Step up on your strength training

Strength training will help maintain (and increase) muscle mass and bone health, as well as increase your HGH levels, all of which will contribute to raising metabolism. Try doing activities that can get your heart rate up for about two and a half hours each week.

  1. Be more careful with the quality of your caloric intake

Make sure you always have healthy food on hand — wholegrain bread, fruits, veggies, low-fat dairy products. Ramp up lean protein intake and reduce simple carbohydrates. It helps to improve muscle regeneration and lessens the impact of simple sugars turning into fat.


Your metabolism in your 40s

By 40, your cells aren’t regenerating as quickly, which could mean that even with all of your great efforts to build muscle by strength training, you might not be getting immense returns for your efforts. Don’t be discouraged; training is still valuable and you should definitely keep it up!

To maintain the same weight you saw on the scale at 25 when you’re 40, it’s likely you’d need to adjust your food intake (around 200 calories less per day) and up your workouts (up to 2-3 times more minutes each week). The exercises that worked for you 15 years ago might also be different at this point, so experiment with a combination of cardio, strength and HIIT to see what works best for your body.

As you approach menopause, you may also notice more body fat settling around your middle: this is entirely normal and a response to changing estrogen levels, but these added fat cells slow down metabolism even more.

Don’t give up, here’s how you can work it out:

  1. Adjust your activities to the needs of your body

While you could get away with more intense physical activity in your 20s, your body may not be so forgiving now. The result? More aches and pains, especially if you’re already battling arthritis. To avoid injury, do activities that put less impact on your body.

  1. Boost your intake of proteins and antioxidant-rich fruits and vegetables

Consuming sufficient protein and anti-oxidant rich fruits and vegetables will help to promote muscle repair and ward off soreness by destroying free radicals formed during exercise. Note: the amount of protein each person needs varies. Use this online calculator to figure out your personal needs.

What happens beyond your 50s? Your metabolic hormone system changes, and your body will increase production of more “bad” hormones, like cortisol. Maintain hormonal balance by getting enough sleep and your fair share of nutrients. Spreading out your snacks and meals so that you’re grazing every few hours. Don’t skip breakfast. Continue exercising, and you’ll be fine, no matter your age.

Have a healthy tip to share with us? Leave them in the comments below!