When your blood sugar is high, your kidneys get rid of the extra sugar, which makes you have to go to the toilet more often. Constantly having to go to the toilet so badly that you wake up in the middle of the night is an early sign of diabetes.
Because your kidneys are working harder and you're going to the toilet more often, your tissues will lose important fluids. You will feel thirsty all the time if you have to go to the toilet a lot.
Your body works hard to get rid of extra sugar when your blood sugar is high. Doing this is bad for your body as well.
Damage to the small blood vessels in the eye can be caused by high blood sugar. This can make the lens swell, which can make it hard to see. When your blood sugar levels go up and down, your vision may get better or worse.
When your blood sugar is too high, your body works hard to get rid of it. You may feel more hungry because your body is burning off so much of the glucose that you're getting from food.
When your body gets rid of extra glucose, it loses its main source of energy. When it can't use glucose for energy, it starts burning fat and muscle, which makes you lose weight. Loss of 10 pounds or 5 percent of one's body weight without a good reason is thought to be important.
In the same way that damaged eye tissue makes it hard to see clearly, damaged blood vessels make it harder for blood to flow. It's harder for blood to get to the hurt area, so even small cuts and wounds can take weeks or months to heal. Cuts and wounds that haven't closed yet are more likely to get infections, which raises the risk of having to amputate.
Nerves can be seriously hurt by having high blood sugar. Over time, this damage can get worse and cause pain or neuropathy. It can start with tingling or numbness.