1. It is thoroughly not reduced a weight
The more too much calorie restriction you take, the more stopping a scale. Let’s say when you continue to be less 1,200 Kcal in a day and doing endurance such as, running everyday, your body goes to that point above mentioned.

Why is that happened? Because it stops thyroid hormone function(meaning it’s dead). It is the thing that producing fat burning hormones such as, T3 and testosterone. But when you keep restrict calorie intake less, it will stop its productions and in return for that, cortisol will be produced as you know that it makes you and your body be stressed. When it is secreted...
- getting worsen of insulin resistance
- getting worsen of leptin resistance
They will occur for you.
It goes to maintain a fat so that a weight does not goes down even you try hard to reduce calorie.

2. Dramatically change a blood glucose level
It is as same as too much taking of carbohydrates and so shortage of calorie.

Chronic shortage of calorie, because of hypoglycemia(low blood sugar).
When it is below about 70mg/dL...
- Severe hunger
- Anxiety
- Shevering
- Dizziness
- Excessive sweating

3. Drastic changing your mood
It is of course, the matter of shortage of calorie. It will bring to make selfcontorol lower. In result, it will make you weak stress or go impulsive behaviors or vent your anger at random... which you don’t want it. So let’s make up more meal amount.

4. Can’t sleep
Reason
A. In the night, the liver stabilize blood glucose levels, producing glycogen.
B. But because of shortage of calorie makes also shortage of glycogen in the liver(or none of them).
C. So your whole body will be extreme condition and can’t you sleep.
Let’s take reasonable amount of carbohydrate, means taking a moderate amount of rice or bread or pasta etc.

5. Severe diabetes
When I worked at the airport, I took too much dietary restriction so I got severe diabetes in several years till finding dietary method right now. It was so bad...really.

The reason why...
It a cause of blunting of thyroid function. T3 hormone in the thyroid has their characters to stimulate intestines function.
So...
A. Shortage of calorie makes amount of T3 gets down.
B. Intestines don’t work satisfactorily.
C. It will go to chronic diabetes.

6. Severe poor circulation
I experienced it already too...(in fact, continuing till now sadly)
Reason why...
A. Lowering Homeostasis hormone
B. Lowering insulin level