What Is Metabolism And How Can We Impove It?

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What is Metabolism?

The word “metabolism” is tossed around a lot these days. Especially in all things health. We often see articles that offer solutions on: How to speed up your metabolism, how to boost your metabolism, what vitamins to take to improve your metabolism, how to stop your metabolism from slowing down.

But why do we want a faster metabolism and what the heck even is metabolism?

If your metabolism is slow you may put on weight easily, find it difficult to lose weight, gain fat in new and previously slim areas or have poor skin and hair condition.

What is metabolism and how can we improve it?

Metabolism is the word to describe all the complex biochemical reactions in your body. It’s how you take in nutrients and oxygen and use them to fuel everything you do. It’s pretty damned important and as such, we need to look after it.

Your body has an incredible ability to grow, heal, and keep you alive. And without this amazing biochemistry, you would not be possible.

  • Metabolism includes how the cells in your body allow:
  • Activities you can control such as walking, running or exercise
  • Activities you can’t control: your heartbeat, wound healing, processing of nutrients & toxins, etc
  • Storage of excess energy for later

Putting all these processes together into your metabolism and having it work just right is incredible but if the conditions aren’t in balance it can mean that your metabolism is either too slow or too fast.

Which brings us to the “metabolic rate”.

Metabolic Rate

This is how fast your metabolism works and is measured in calories. THAT WORD! That word that we love to hate.The calories you eat can go to one of three places:

  • Work – exercise and other activity
  • Heat – from all those biochemical reactions
  • Storage – extra leftover “unburned” calories stored as fat.

The more calories you burn as work or creating heat the fewer “leftover” calories there are to store as fat for later and the easier it is to lose weight and keep it off.

There are several ways to measure metabolic rate. One is the “resting metabolic rate” (RMR) which is how much energy your body uses when you’re not being physically active.

The other is the “total daily energy expenditure” (TDEE) which measures both the resting metabolic rate as well as the energy used for “work” like exercise, throughout a 24-hour period.

What affects your metabolic rate?

Oh boy! It would be easier to say what doesn’t affect your metabolic rate.

The thyroid

The gland at the front of your throat that releases hormones to tell your body to “speed up” your metabolism. Of course, the more thyroid hormone there is the faster things will work and the more calories you’ll burn. So keep your thyroid healthy with cruciferous veg like broccoli, cauliflower, cabbage and kale as well as brazil nuts for selenium.

Let’s not stop there.

How big you are counts too! Larger people have higher metabolic rates, but your body composition is crucial!

The Importance Of Muscle

Muscles that actively move and do work need more energy than fat does. So the more lean muscle mass you have the more energy your body will burn and the higher your metabolic rate will be. Even when you’re not working out. Woohoo. Build that lean muscle mass and it will keep you looking lean and toned.

This is why weight training is often recommended as a part of a weight loss program. Because you want muscles to be burning those calories for you. When you lose weight your metabolic rate often slows down which you don’t want to happen. So you definitely want to offset that with more muscle mass and cutting down simple carbohydrates like sugar and grains.

Increasing Your Heart Rate

Aerobic exercise also temporarily increases your metabolic rate. Your muscles are burning fuel to move so they’re doing “work”.


Your body also burns calories to absorb, digest, and metabolize your food. This is called the “thermic effect of food” (TEF).

You can use this to your advantage when you understand how your body metabolizes foods differently.

Fats, for example, increase your TEF by 0-3%; carbs increase it by 5-10%, and protein increases it by 15-30%. By trading some of your fat or carbs for lean protein you can slightly increase your metabolic rate.

Studies have also shown the TEF of highly processed foods as being substantially less that of whole foods, which makes complete sense. A doughnut which is high sugar, high fat and therefore high carbohydrate will turn into energy easily and so will increase your TEF very little. Wholefoods, on the other hand, take a bit more digesting and release energy into your system slowly increasing your TEF more.

Couple that with the fact that course food may even pass through your body without even being digested so the calories will be lost out the other end and you are on to a win.

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

For a super simple protein recipe try my Lemon Herb Roasted Chicken Recipe. It ticks all the boxes.

Mind & Body

In all this, we mustn’t forget the mind-body connection. Research shows the influence that stress and sleep have on the metabolic rate.

Cortisol, the hormone released during times of stress, actually increases your metabolism, but it also makes you hungry.

Sleep deprivation can cause cravings. When you are sleep deprived the levels of Leptin in your body, the hormone that decreases hunger lowers while Ghrelin, the hormone that increases your appetite goes up.

Your metabolism is a complex system. Look after it and it will look after you.

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Jane Lamason

Hi, I'm Jane. I'm a certified health and life coach and the owner at janelamason.com. I help women over 50 navigate menopause and life beyond fifty. I offer simple strategies for improving your health naturally and encourage women to take control of their own health in ways that don't impact on their lifestyle or time.

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