Where does fat go when we lose it?

Many of us are striving to lose weight, but what do we really mean by that?

We think that what we actually mean is we want to lose fat. We don’t want to lose muscle. We definitely don’t want to lose bone. So what we are trying to get rid of fat.

But have you ever thought about exactly how fat leaves your body?  We have a topic on this in our Amabassador and Reset Restart courses, but many people don’t actually know where fat goes.

A common misconception is that it changes to muscle. This is actually impossible, because the composition of fat and lean muscle is chemically different. To change our body composition we lose weight and build muscle in two separate metabolic processes.

Scientists from the University of New South Wales posed this same simple question to 150 health professionals: When somebody loses weight, where does the fat go? And, incredibly, of the 150 doctors, dietitians, and personal trainers they surveyed, only three  out of 150 respondents (that’s 2%) answered the question correctly.

Some of the misconceived answers were:

“Fat is converted to energy”

“Fat was converted into muscle”

Or that “it leaves the body through the colon”

Around 25% didn’t have a clue.

But what actually happens to fat in our bodies as we lose it is a series of complex metabolic processes.

So what’s the answer?

First we must understand how and why we store fat in our bodies. When we consume food, any type of food, whether it is carbohydrate, fat, protein or fibre it enters our body and is broken down into its different molecules by the chemicals in our stomachs, intestine and colon. The molecules are used for various things – cell and organ regeneration, cell and organ function, nerve stimulation and signals, energy release from cells, the list goes on.  The molecules that aren’t used, depending on what they are, can be released as waste in the urine, or stored for future use in places like the liver, muscles, and the molecules required for energy are stored under the skin as adipose tissue, within fat cells.

When the body goes into calorie deficit, it needs to break the fat cells down to release energy for our body to function and move. But the whole fat cell isn’t converted into energy, it is broken back down into its individual molecules and then the energy is released back into the muscles, and the rest has to go somewhere else.

The scientists at the University of  New South Wales went on to do some very complex calculations but ultimately found that when we lose weight, or fat, to be more precise, our cells use the released energy, but then there is a lot of waste molecules, which need to leave the body.

They leave the body through two main ways.  The first and largest percentage (84%) our lungs, excreted as Carbon Dioxide and the rest (16%) is excreted as water through urine (mainly), sweat, breath, tears and other bodily fluids.  The scientists wrote in their article “If you lose 10kg of fat, precisely 8.4kg comes out through your lungs and the remaining 1.6kg turns into water. In other words, nearly all the weight we lose is exhaled.”

If you are a science lover you can read their full report in the British Medical Journal.

The article went on to say how using physical activity as a weight loss strategy alone, can easily be foiled by the food we put into our bodies, so it is important to embrace, the ‘eat less, move more’ strategy, that Be Strong promotes.

This week!

So this week, stay on track with your calorie deficit and every time you get out of breath, get a sweat on, or you go for a wee,  that is the excess fat that you are trying to get rid of,  leaving your body.  Stick at it, stay positive and keep moving!

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