Reading Time: 4 minutes 'Our metabolic rate isn’t fixed for life...' Credit: Adobe. Do not use without permission.
Reading Time: 4 minutes

What is metabolism? You may have heard the word, but what actually is it? Also, what is the effect of a fast, normal, or slow metabolism?

Metabolism covers the biochemical reactions in your body that use nutrients and oxygen to create energy.

Your metabolic rate is the speed the metabolic actions occur and is measured in calories, so in simple terms a fast metabolism converts food into energy quicker than slow.

If you have a fast metabolic rate you will often be able to eat more food without gaining weight, than someone with a slower metabolism. 

What affects your metabolism? 

How fast your metabolism works will be down to several factors. Some people will have naturally fast metabolisms. 

We probably all know someone who seems to eat whatever they like and never puts any weight on! 

Some common reasons why your metabolism may be slow include your size and body composition, how active you are, how much sleep you’re getting and if you have a history of dieting. 

Body composition

You may think a larger person has a slower metabolism than a smaller one, but in general, the opposite is true. More energy (calories) is required to fuel a larger body than a smaller one. 

The percentage of your body that is fat and muscle will also have a bearing because muscle burns more calories than fat. Your resting metabolic rate will be lower the less muscle you have. 

How old you are

Our metabolic rate isn’t fixed for life. Unfortunately, our muscle mass naturally decreases as we get older. 

This in turn will affects your metabolism because your body composition will be changing. 

But there are things you can do to offset some of these less than positive changes. 

History of dieting

There is some evidence to show that dieting can result in a loss of muscle, as well as fat, if not done in a healthy, sustainable way. 

The reason why dieting has an impact is because often with a lot of diet regimes the emphasis is on rapid weight loss and quite extreme calorie reduction. If you lose weight quickly by restricting calories too much the chances of you losing muscle as well as fat are higher. 

If you put weight back on, which is very likely, this can go on as fat. So each time you lose weight and put it back on you’re changing your body composition to have a higher fat percentage. 

So it’s important that if you’re looking to lose weight you need to eat enough food to fuel your body, without overdoing it. 

If you think your metabolism is a bit sluggish there’s plenty you can do to help speed it up.

What to eat to boost your metabolism

The answer is ensure you’re eating enough protein. Your body burns calories to absorb, digest and metabolise food. 

This is called the “thermic effect of food” (TEF). Fat, carbs and protein increase your TEF by different amounts. Fats, for example increase your TEF by 0-3%, carbs increase it by 5-10%, and protein increases it by 15-30%. By swapping some of your fat or carbs for plant-based protein you can slightly increase your metabolic rate.

Another bonus of protein is that your muscles need it to grow. Working your muscles and feeding them what they need will help you to lose weight and keep it off.

Useful sources of protein

Some great sources of plant-based protein include:

  • Tempeh
  • Tofu
  • Lentils
  • Beans
  • Chickpeas
  • Nuts
  • Seeds 
  • Nut butters
  • Teff flour – this might be unfamiliar to you, but it’s a naturally gluten-free flour that can be used to make things like pancakes. It has a delicious chocolatey, nutty taste. 
  • Peas
  • Whole grains such as quinoa, millet and amaranth

Ensure you are eating a wide variety of these foods and you will get all the protein you need.

Lift those weights!

Doing some exercises using weights or your own body weight is a great way to boost your metabolism. You don’t need to worry about bulking up.

The idea is to increase the amount of muscle you have. The more muscle you have the more calories you burn – even when you’re not doing anything! 

Increase your activity levels

This doesn’t have to be ‘exercise’ in the formal sense. Just think about how you can be more active throughout the day, especially if you’re deskbound. 

If you find yourself sat at your desk for hours without a break set yourself an alarm. 

If you’re very busy and feel you don’t have time for exercise, try reframing this and consider where you can fit some activity into your day. Here are some ideas:

  • Going for a quick walk at lunchtime
  • Using a standing desk instead of sitting all day
  • Taking the stairs instead of the lift
  • Taking stars two at a time – great for working your large leg muscles 
  • Doing a few squats or lunges when you’re waiting for the kettle to boil

These can all contribute to you being more active. 

Lack of sleep

You may be wondering what sleep has to do with your metabolism. 

But if you’ve ever craved sugary foods when you’re tired you know what impact sleep can have on your food choices. This is because your brain is saying ‘I need some energy’ and sugar is the quickest way to get that. 

As well as influencing what you eat there’s research that shows the influence that sleep has on your metabolic rate. One reason is because a lack of sleep impacts the levels of the hormones responsible for signalling to your brain when you’re hungry and when you’re full.   

Everyone is different of course but the general recommendation for good health is to get 7-9 hours of sleep every night. Aim to create a routine that allows at least 7 hours of sleep every night. 

Coral Sirett

Coral Sirett is a vegan weight loss coach, qualified nutrition adviser, workplace wellbeing consultant, speaker and the founder of Zest Health. Based in the UK, she works with clients worldwide offering private health coaching and consultations, a personalised nutrition report, and an online programme. Coral adopts a gentle and sustainable approach with clients as she believes lasting healthy change should be an enjoyable and positive experience. Find out more at zest-health.com.