Have you tried the Master Cleanse and got great results only to gain all the weight back, plus more and find losing weight a little harder now?

Crash diets obviously work to help us lose weight fast! Otherwise we wouldn’t be doing them. But do they work long term? What is the side effect on your metabolism?

First I need to explain to you what your metabolism is and how it works.

We commonly know it as the total number of calories an individual burns at rest, otherwise known as your resting metabolism. There are two systems that make up the metabolism and need energy (calories) that we will focus on in this article – the nervous system and the muscular system.

The nervous system needs energy depending on the brain power and frequency at which it is used. Type A people, who talk fast, walk fast, and do things fast would need more energy than the stereotypical surfer dude who talks slow, moves slow and is often very “chill”. The reason why fat burning pills work is that they put your nervous system into overdrive and therefore you burn more calories. Supplement companies often add extra caffeine and caffeine type herbs to their products to help you burn those extra calories and give you extra energy, but the problem is that there is a price to be paid. Depending on your current health conditions, fat burners and extra caffeine can have negative effects on your heart, brain, hormones, and moods. This can be very dangerous, so please stay away from fat burning pills. Rather than manipulating your nervous system, I would recommend focusing on the muscular system.

What Happens to Your Body When You Crash Diet?

Muscles are active tissue – they need energy. Fat is not active and needs nothing!  The more active tissue you have, the more energy (calories) you need. As we age or become less active, we often lose muscle, which decreases our resting metabolic rate. Women especially are often stumped when they gain weight over a period of time and are shocked because nothing has really changed about their diet or exercise—they have lost muscle over time.  The good news is you can get it back and more!

So, what EXACTLY happens to your body when you crash diet?

Crash diets can be compared to starvation diets. Your resting metabolism is the amount of energy your body needs to live with the current body fat to lean mass ratio you have. When you digest your food, depending on what you are eating and how it breaks down, your body releases energy into your bloodstream (blood sugar) for you to fuel your activities. When there is not enough blood sugar available to fuel your body (think gas in a car), then the body will break down your muscle tissue and convert that into glucose to fuel your body. If your body needs to use your muscle tissue as energy, then your lean mass will decrease, and so will your resting metabolism.

Another factor that can wreak havoc on your system is the stress related to breaking your own tissue down for fuel and then any added stress from being on a starvation diet for too long. Studies have shown that there may be benefit in intermittent fasting, but I am addressing week long periods of an extremely reduced caloric intake.

Stress and not getting enough sleep can cause elevated cortisol levels. Eating processed foods, too much meat, drinking coffee and alcohol all make your bodies’ ph more acidic. These factors can dehydrate you and imbalance your hormones making it very difficult for the body to use fat as energy and to excrete it from your system.

Bottom line is that if you want to lose weight there are safer, more effective ways to do it than a crash diet.  While the short term results may be tempting, the long term effect can set you back and slow down your ability to lose weight and keep it off for the long term.

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Pollyanna Hale Health and Lifestyle coaches
Lost 13 Kg in Total
Mel, 32y Location: London, United Kingdom Working with Pollyanna changed everything. I lost 13kg, got toned and have more energy than ever! Get same results!


Chriz Zaremba Fitness Consultant
Lost 45 Kg in Total
Chris, 50y Location: London, United Kingdom Lost 45kg after the age of 50 and now competes and wins physique competitions and runs marathons Check our weight loss plans