Because type 2 diabetes develops slowly, and symptoms generally come on gradually, they may go unnoticed for a long time, or they may be attributed to something else.
For example, increased thirst may be chalked up to a hot summer, or fatigue may be interpreted as a sign of aging or stress.
This is unfortunate, because even short-term high blood sugar diminishes your quality of life. And if high blood sugar persists for a long time, it can eventually cause complications such as eye or kidney disease that cannot be completely reversed with improved blood sugar control.
Type 2 diabetes can cause a wide range of signs and symptoms, including:
  • Fatigue
  • Dry mouth
  • Thirst
  • Excessive urination
  • Hunger
  • Weight loss
  • Blurry vision
  • Cloudy thinking
  • Irritability
  • Wounds that won't heal
Frequent infections may also be a sign of type 2 diabetes. In women, vaginal yeast infections are particularly common. Yeast infections can also occur on the skin and, in men, in the groin.
Other infections associated with undiagnosed type 2 diabetes include gum infections, urinary tract infections (particularly in women), slowly healing wounds with subsequent infections, and infections of the feet.

Symptoms in Men

Type 2 diabetes symptoms are generally the same for men and women.
However, urological problems such as erectile dysfunction (ED) — the inability to achieve or maintain an erection — have been associated with all forms of diabetes, including type 2.
According to the National Diabetes Information Clearinghouse, 20 to 75 percent of men with any type of diabetes have ED.
Researchers believe diabetes causes sexual function problems in men due to damage to the body's autonomic nervous system (ANS), which controls circulation.
If you have the symptoms of ED, it may be a sign you have diabetes.

Another urological problem associated with diabetes in men is retrograde ejaculation, or the release of semen into the bladder during ejaculation. Symptoms include reduced semen during ejaculation.

Symptoms in Women

Women with type 2 diabetes are at increased risk for vaginal yeast infections.
This is because type 2 diabetes has been associated with increased yeast in the vaginal area.
Experts believe these vaginal infections will also lead to urinary tract and bladder infections, as both yeast and bacteria multiply when blood sugar is elevated.

What Causes Type 2 Diabetes Symptoms?

All of the signs and symptoms of type 2 diabetes are caused by high blood sugar and/or insufficient insulin:

Excessive urination (polyuria): When the concentration of glucose in the blood rises above normal levels, your body attempts to dilute your blood by pulling fluid into your bloodstream. At the same time, the high level of glucose in the fluid entering your kidneys causes them to discharge large amounts of glucose as urine, rather than reabsorbing it into the body as they normally would. These two processes together result in large amounts of fluid being lost through urination.

Thirst (polydipsia): As the amount of urine being excreted increases, your body starts to feel
dehydrated, prompting you to feel thirsty and drink more. If you reach for sugary drinks to quench your thirst, the problem becomes worse.

Dry mouth: Dry mouth goes hand in hand with increased thirst, as high blood sugar and excessive urination dehydrate your body.

Fatigue: Normally insulin allows glucose into the cells, where it's used to fuel cellular functions and stored for future energy needs. If there is not enough insulin, not much glucose gets into your cells, and your body is literally “running on empty.” In addition, if excessive urination is interrupting your sleep, you may feel fatigued from lack of sleep.

Hunger (polyphagia): Similar to fatigue, hunger is caused when the glucose from food stays in your bloodstream rather than being transported to your cells where it's needed for fuel. Eating more food doesn't help and, in fact, makes things worse by raising your blood sugar levels even higher.

Weight loss: When large amounts of glucose are being excreted in your urine, the calories that that glucose would have provided are being lost as well. The effect is the same as consuming fewer calories in the first place.

Blurry vision: Normally, the lens of your eye changes shape as you focus on objects that are nearby
or far away. But when your blood sugar is high, your lens becomes swollen and unable to change shape to focus.

Infections: The bacteria and fungi that cause infections thrive on sugar, so more sugar means more food for them. In addition, high blood sugar slows blood circulation, meaning infection-fighting white blood cells can't get to where they're needed as quickly.

Wounds that won't heal: High blood sugar impairs parts of your immune system that are needed for fighting infections and healing wounds. Wounds also need oxygen to heal, and any slowdown in your blood circulation slows oxygen delivery throughout your body.

Cloudy thinking: Your brain uses a lot of glucose to fuel its various functions, and when it can't get that glucose (because of insufficient insulin), the result can be difficulty thinking, remembering, and staying focused. You may even become disoriented.

The good news is that bringing blood sugar levels down to normal levels can alleviate all of these signs and symptoms. And the earlier these symptoms are noticed — and the earlier a person can be tested for type 2 diabetes — the better!