When you wake up with a cold, you know you’re sick pretty much right away. The sore throat and stuffy nose are dead giveaways. But when you’re sick with diabetes, the symptoms are much less obvious. In fact, new studies show a shocking 25 percent of people with type-2 diabetes don’t even know they have the disease.

This isn’t to say diabetes doesn’t have warning signs. However, the early signs of diabetes are subtle enough in the beginning and even middle phases that you might not notice something is off. This can be dangerous because the longer you go without controlling diabetes, the greater your risk for developing serious health complications like heart disease, kidney disease, amputation, and blindness.

If you have risk factors for diabetes, such as family history or being overweight, and have experienced any of the following early signs of diabetes, talk to your doctor about getting a blood test that can diagnose the disease.

1. Frequent bathroom breaks

When there’s extra glucose in your blood, your body gets rid of it by flushing it out in your urine. Having to use the bathroom several times during the night is a clue you should pay attention to.

1. Feeling thirstier than usual

Frequent urination causes you to become dehydrated. In turn, you may feel the need to drink more water than usual. If you have a dry mouth regardless of how much and how often you hydrate, this could be an early warning sign of diabetes.

1. Extra hungry and shaky

When your body has a problem regulating its glucose and you eat something high in carbohydrates, your insulin level will spike and your blood sugar will drop quickly. This can make you feel shaky and have you reaching for more carbs or sugar.

1. Constant fatigue

It’s normal to feel exhausted from time to time, but if you’re constantly fatigued it may be a sign that something else is going on. Feeling extra tired and sluggish could mean the food you’re eating for energy isn’t being broken down and used by your body as it’s supposed to.

1. Foot pain and numbness

Diabetic neuropathy, or mild nerve damage, is most common in people who have had type-2 diabetes for 25 years or more. However, foot pain and numbness can occur in the pre-diabetic phase and should be monitored closely.

1. Blurred vision

Blurred vision occurs when there are rapid changes in blood sugar and the eye muscles have not yet adapted. This isn’t permanent, though. Your vision will return to normal about six to eight weeks after your blood sugar is normalized.