Whether you are a newly diagnosed diabetic or you have had diabetes for many years, one of the most critical aspects of blood sugar control is the profoundly negative effects of high blood glucose levels on the immune system. Infections, especially gum, bladder, and kidney infections, can wreak havoc on diabetes control. And poorly controlled blood sugars can feed gum, bladder, and kidney infections.

Diabetes guru Dr. Robert Bernstein notes that a kidney infection can triple insulin requirements overnight. My personal experience from taking care of family members has been that older diabetics especially tend to get "loopy" when they have bladder infections. The combination of the stress of the infection and the stress of high blood sugar levels creates a kind of dementia that, fortunately, usually abates when the infection is brought under control. Scientists at Finland's Päijät-Häme Central Hospital note that the problem is especially severe when steroids are administered to treat or prevent shock by a "shot" (bolus injection) rather than by a "drip" (intravenous infusion).

Pneumonia can pose an even greater stress on diabetics. A study at Wake Forest University found that the average insulin (Humalog) requirement in diabetics suffering pneumonia after injury went up from 7 to 26 units a day, a nearly four-fold increase.

But what if you are diabetic but you are not an older person with a bladder infection or a crash victim suffering pneumonia?

There are two kinds of infections diabetics of all ages need to be careful about.

One is the common cold. The effect of a cold on insulin requirements is less dramatic than the effect of pneumonia, but it is not unusual for blood sugars to soar the day before cold symptoms are noticeable. That's why keeping kids infection free benefits every diabetic in the household and diabetics should be especially careful not to feed a cold with any sugary food.

An even more serious problem is any kind of gum infection. Gum disease and diabetes make a vicious circle. Gum disease can cause high blood sugars, and high blood sugars feed the bacteria that cause gum disease. Whenever your diabetes medications or insulin aren't "working," the first place to look is your mouth.

See if there is any sign of infection, tenderness to pressure, swelling, or redness of the gums. Then put some water with crushed ice in your mouth for a minute. If a tooth hurts, there may be a gum infection.

Whenever you have even the hint of gum infection, make an appointment with your dentist as quickly as possible, even on an emergency basis. Gum infections are very common in diabetics and it is essential to bring them into control to keep blood sugars and insulin requirements down.