People often starve themselves, thinking that by having a low extremely low calorie diet will help them lose weight more efficiently.

Yes, “Calorie Deficit “ is undoubtedly important in burning fats off your body. However, if your calorie deficit is too extreme ( i.e to the extent of consuming only at most 1000 calories a day ), this kind of diet plan will only do more harm rather than doing good to your body.

Having a large calorie deficit diet plan will only work in the beginning. Over time, when you continue to cut your calories too far, your body will think that you are about to starve to death and they will do something to protect you.

This defence mechanism set up by the body is known as the “starvation response”

And this is what will happen thereafter:

1. Your body will release fewer fat-releasing and fat-burning enzymes such as hormone sensitive lipase and lipoprotein lipase.

When your body release fewer of these fat-burning enzymes, you will find yourself harder to burn fats than before.

2. Your fat cells will release less of the hormone leptin – the hormone responsible for sending the signal to your brain, telling your brain that you are well-fed and not starving.

3.Fat burning hormones crash, including your levels of T3,T3 is the active form of thyroid hormone, the important "metabolism-regulating hormone"

4. You lose muscle.

Muscle is metabolically-active tissue. This means that it takes a lot of energy to keep the muscle. When your body realise that you are in starvation mode, they will ensure that you have consumed enough energy to keep the body functional. Therefore, the body won’t feel a need to keep the muscle anymore. In other words, the excess muscle become expendable and your body will cannibalize on your own lean tissue.

In conclusion , It’s not physically possible for you to achieve permanent fat loss by starving yourself.

Any diet program with extreme low in calories will only work in the short term . In the long run, these extreme “Calorie Deficit” diet will lead to binge eating and weight re-gain, causing you to have lesser muscle and a lower metabolism than when you started.