METABOLISM 101

Nutrition

METABOLISM 101

When the subject of weight loss is discussed, you usually don’t have to wait long for the word metabolism to crop up. Terms like “boosting your metabolism” and “basal metabolic rate” are described as being important for fat loss. But what do these terms actually mean?

Here we will try and explain the basics of metabolism so you can decipher the terms so often used in fitness articles, and understand how you can maximize your metabolism to lose weight and burn fat as efficiently as possible!

TOTAL DAILY ENERGY EXPENDITURE (TDEE)

The number of calories you need per day is collectively called your total daily energy expenditure or TDEE for short. TDEE is made up of several things – all of which are linked to metabolism.

If you can increase your TDEE while eating slightly fewer calories than you need, your body will burn fat to make up the energy shortfall. There are several ways you can maximize your TDEE to create this deficit!

BASAL METABOLIC RATE (BMR)

Your basal metabolic rate, BMR for short, is the number of calories you need to sustain your weight without factoring in exercise and physical activity, while you are in a fasted state. Pretty much the number of calories you would burn laying in bed all day.

BMR is directly related to your muscle mass. The more muscle you have, the more calories you need on a daily basis. Many people are very reliant on cardio for weight management but building muscle can be just as effective.

Like a car with a bigger engine will burn more fuel than a car with a smaller engine, increasing muscle size – even slightly – can increase your BMR which will lead to a greater calorie expenditure even while you sleep. 

THERMIC EFFECT OF FOOD (TEF)

We get calories from the food we eat and the fluids we drink. Fat provides nine calories per gram, protein, and carbohydrate contain four calories per gram each, and alcohol contains seven calories per gram. However, not all calories were created equal.

Protein, carbohydrate and fat all require energy to break them down; but the amount of energy, which is measured in calories, varies from one food group to the next. The amount of energy it takes to ingest, digest, process and absorb the food you eat plus eliminate the waste is called the thermic effect of food – TEF for short.

The thermic effect for the three main food groups is:

  • Protein: 20-35% of calories burned through processing

  • Carbohydrates: 5-15% of calories burned through processing

  • Fats: 0-5% of calories burned through processing

The more protein you eat, the higher your metabolic rate will be. In simple terms, if you eat 200 calories worth of protein, your body will use between 40 and 70 of them indigestion. The most common estimate for the total thermic effect of food is around 10 percent of your total caloric intake, but as your protein intake increases so does this number.

Many diets state you must eat a specific number of calories per day to lose weight but, if more of your calories come from protein, you can lose fat faster. This helps to explain why high protein, low carbohydrate diets are so effective for weight loss. 

THERMIC EFFECT OF ACTIVITY (TEA)

BMR describes your energy expenditure at rest and in a fasted state. As you now know, eating (especially protein) uses energy and, of course, so too does an activity. The energy cost of getting up and moving is called the thermic effect of activity or TEA for short.

An activity can be something as simple as walking to work, walking to the water cooler or something more purposeful such as a workout. All physical activity uses energy and the more energetic you are each day, the higher your energy expenditure will be.

Being sedentary means it’s much harder to create the necessary calorie deficit to lose weight; your diet would have to be very low in calories and you’d probably feel hungry all the time. That’s why exercise is an important part of losing weight.

Exercise doesn’t only burn calories while you are doing it, it also increases your metabolism after exercise. The harder the workout, the longer your metabolism will be elevated (called EPOC).

TEA is arguably the most variable contributor to your TDEE. You could spend virtually all your time seated and inactive, or you could exercise and burn a lot of calories.

SO HOW DOES THIS ALL ADD UP?

If you want to lose weight as efficiently as possible, you need to work to optimize your metabolism. Increasing your TDEE while eating a little less will ensure you create the necessary calorie deficit to force your body to burn fat. Steps to maximizing fat loss through metabolic optimization include:

  • Increase your BMR by building muscle.

  • Eat more protein to maximize the thermal effect of food.

  • Exercise and be more physically active to increase the thermal effect of activity.

If you want to lose weight as efficiently as possible, it makes sense to increase your total daily energy expenditure. Building muscle, eating more protein, and being more physically active are the best ways to do this. Use the tips in this article to get your metabolism “on side” to maximize fat burning.