Metabolism and Weightloss*

Saturday, 16 July 2016, By Sarah Camilleri

You often hear that losing or gaining weight is all about the balance between "energy in" & "energy out". Now, while this equation doesn't fully capture the complex process of weight gain or loss, for simplicity sake it's a nice model to work with. It makes sense to think of it as a balance between what's coming in, and what's going out. Just like saving money: if you expend more than you take in (or spend more than you earn!) you'll lose weight (lose money!).

So let's look closer at the energy in verses energy out model and see where we can make some good changes for weight loss!

Energy In

We get energy from the various foods and drinks we consume on a day to day basis. How much we eat and the kinds of foods we eat will determine how much energy comes in and this is very important for weight loss. The energy in food actually comes from the macronutrients of: protein, carbohydrate, fats, and alcohol. Each nutrient has the following energy per 1 gram:

o Protein - 4 calories
o Carbohydrate - 4 calories
o Fat - 9 calories
o Alcohol - 7 calories

As you can see, fat has the most calories per gram and this is why it is often singled out (somewhat unfairly) in diet programs and diet foods. You need to see that while fat has the highest energy per gram, consuming too much of any macronutrient will be detrimental to weight loss!

Note that alcohol is also high with 7 calories per gram, and don't forget the sugars that are contained in most drinks e.g. wine, beer, and mixers. Protein and carbohydrates have the lowest energy per gram at 4 calories each.

So how much energy should you be eating each day? The average energy intake for a female is between 1600-2200 calories per day, and for a male between 2000-2600 a day. These approximate amounts will keep your weight at a stable point, anything more will slowly gain weight, anything less will result in weight loss. The actual calories you require will obviously vary depending on their age, size, activity levels, and weight gain or loss objectives.

How do we reduce our calorie intake for weight loss?

o We can eat less at each meal, and over the whole day, so aim to reduce your portion sizes.
o We can also try eat foods that are less energy dense, so we can eat a low amount of calories but still feel full.

Energy Out

Balancing against the energy coming in we have the energy which is going out! Remember that we want to create a calorie deficit for our weight loss to be successful! Energy is used in three main areas: activity, eating, and maintaining bodily functions. These three areas add together to become your metabolic rate or total energy expenditure each day. How big your metabolism is depends on these three main factors, but genetics plays a part too!

Activity: no points for guessing this one - the more we move, exercise, and keep active the more energy we will burn each day. Moving gets the fat burning! More activity over time also increases our metabolism. Every time you walk, run, cycle, or even fidget at your desk it's burning energy. You will use approximately 15% of your total energy each day moving around, with training or exercise extra to this. So try and incorporate as much activity into your day as possible - always look for the opportunity to MOVE!

Eating: surprisingly enough eating gives us what is known as the 'thermic effect of food' and accounts for approximately 15% of total energy used. This means it takes energy to break down our food and digest the macronutrients, so every time you eat you are not only taking energy in but also burning a small amount up. This is why small and frequent meals can help create a higher energy expenditure over the whole day than larger less frequent meals.

Bodily functions or BMR (basal metabolic rate): the majority of our energy expenditure is our metabolism which is used to maintain our bodily functions or keep "the engine running". Approximately 70% of our daily energy is spent merely keeping us alive, and this is referred to as our basal metabolic rate or BMR. Our total lean muscle mass accounts for the majority of our BMR, because muscle is an active tissue that needs energy 24/7 to keep alive.

So how can you change your lean mass? First thing is DO NOT go on a low calorie diet! Reducing calories to extreme lows can cause your body to catabolise lean muscle mass and this has a terrible effect on your metabolism, amongst other bad things! Second, DO start weights training and exercising as this will increase your lean mass! Don't worry, you won't turn into the Incredible Hulk by lifting a few weights.

So what can we do to burn more energy each day?

We can control:

o how much we move (keeping active, keep exercising and look for opportunities to move)
o how much lean mass we have (resistance / weights training is best, but all forms of movement help to a certain extent)
o how often we eat (small frequent meals verses large less frequent, so try 5-6 small rather than 3 big meals)

So I hope this information lets you know more about how your metabolism can help you burn fat or burn energy and make the whole process of weight loss much easier! The thing to remember is that it won't be a quick solution and you need to put in the work to achieve great things. Find a friend or a Personal Trainer who can help you make the changes necessary to kick-start your metabolism, get the fat burning, and get a great healthy long term weight loss.

*Disclaimer: Individual results vary based on agreed goals. Click here for details.

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