Foods & Its Effect on Your Metabolism

by RickBrennan 10216 views Nutrition

Foods & Its Effect on Your Metabolism

Having an efficient metabolism is the key to maintaining a healthy weight and having sustained energy levels. The food we eat plays a major role in our metabolism and the speed in which it operates.  Understanding how our metabolism works can influence our body’s metabolic response and by following a nutrition plan consisting of 5 core food groups (look out for my next article) allows us to stay lean and healthy all year round.

The thermic effect of the digestion, absorption and transportation of the food we eat has a follow on effect to our total daily energy expenditure. 

When looking at dietary intake and its effect on metabolic health, the percentage of protein, fats and carbohydrates that make up our diet has by far the biggest impact on our metabolism. 


Protein has the greatest thermic effect of all macros. A significant portion of the calories consumed from protein sources is required for absorption and digestion giving protein a far greater metabolic advantage.

Your body burns more calories attempting to break down protein than it does any other macronutrient.

Protein is the key component that the body requires in order to build and repair our muscles and when you consider the notion that the more muscle your body holds the more fat you will burn throughout your day, you can understand why resistance/weight training has become so popular.



Carbs are second on the thermic effect of food (TEF) list with a portion of the calories consumed being burned in the process of digestion and assimilation. There are even some great non-starch, high fibre carbs, like celery, which essentially cancel themselves out.

What I mean by this is, they burn up to, if not equal to, the same amount of calories during the digestion process as they offer from their caloric value.

These foods are great to eat as they offer both a high nutritional value and they leave us feeling satisfied for longer, which in turn can stop us snacking on extra calories between meals.

But what about other carbohydrate sources, are they all the same?

We often hear people talk about sugar being the enemy but really what a lot of people don’t actually realise is that sugar comes in many forms. Simple sugars come in the form of things such as lollies, cakes, soft drinks and juices and complex carbohydrates/starches are things like oats, sweet potato and rice.

Regardless of their differences, they all eventually get converted by the body into glucose.

It is the time it takes for this conversion that makes all the difference...

Simple sugars digest faster, which can lead to insulin/energy spikes, whereas complex carbs provide a sustained energy release, which is a lot better for controlling your weight as it will minimise energy slumps, cravings and general hunger. Once a carbohydrate has been consumed, the body either utilises the circulating blood glucose as energy or stores excess glucose as glycogen in our liver and muscles.

Knowing this, an important aspect to remember is once our glycogen levels are full, especially when we are in a caloric surplus; our body will store carbs/excess calories as fat. 

So as you can see, understanding carbohydrates, the different types and how the GI (glycemic index) works, can have a major impact on our weight loss or our bodies gaining weight.


Fat comes in last on the TEF list, however, fat is an essential part of our diet and nutrition and we can’t live without it. Because of this, manipulating fats for the purpose of manipulating your metabolic rate isn't considered substantial enough to micromanage. And although fats are essential to human life we only need small amounts to stay healthy.

So how do we implement this knowledge into a daily diet?

Here are some simple rules to achieving an effective metabolism:
  • Carbs are our energy source, not our enemy
  • Drink plenty of water throughout the day - I find having a few glasses prior to each meal stops me from overeating
  • Not all fats are equal, so finding the right balance between polyunsaturated/monounsaturated fats and saturated/trans fats can be the difference between healthy thyroid function, energy levels and hormonal health.
Foods that help enhance metabolic health:
  • Citrus Fruits e.g. grapefruit
  • Foods high in omega-3s e.g. salmon
  • Calcium rich foods
  • Coffee
  • Spices e.g. chili
  • Apple cider vinegar
  • Green tea
  • Negative calorie foods e.g. broccoli

It is important to remember we all require a specific number of calories from each of the key macro groups to survive.

However, you need to remember that depending on what your end goal is, whether it is fat loss, muscle gain or just maintaining your current shape, that achieving your goal will be reliant on what calories (macros) you consume. Too many calories no matter what macros we are eating will lead to a caloric surplus and regardless of what food we eat, if you are taking in more calories than you are burning each day you will eventually put on weight.


Health Club Owner and Personal Trainer

I have been in the fitness industry for over 20 years as a personal trainer and co-owner of My Fitness Club Broadbeach for the past ten years. I come from a professional football background and hold State, National and World bodybuilding titles. I specialize in rehabilitation, weight loss, competition prep and have clients based in the Gold Coast and from all around the world including New Zealand, Dubai, Ireland and London. I also work with clients all around the world who are unable to see me face to face through my online training packages.

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