What Ketones Are and Why All Diabetics Should Care

If glucose cannot be used for fuel, the body burns fat, creating ketones – a back-up fuel supply that keeps us going.

Most of our cells can use ketones for energy, and the brain can burn ketones for about 75 percent of its fuel needs.

The human body regulates ketone production through a delicate balance between insulin and stress hormones. When this balance is thrown off, the body has no way of putting the brakes on ketone production.

Ketones function as weak acids. Without production brakes, they can build up in the bloodstream, making the blood’s pH too low or acidic. Acidosis is the word for blood that has become too acidic. Ketoacidosis is acidic blood caused by too many circulating ketones.

Because it takes very little insulin to block ketone production, blood sugar can become quite high before ketones become a toxic problem.

How Ketones Become Too Much of a Good Thing

Fat metabolism, or the breakdown of fat for energy (ketones), takes place in the liver. It naturally occurs to keep the body functioning when a person is:

• sleeping and has not eaten for several hours.
• on a low-carbohydrate diet.
• fasting or starving.
• diabetic and does not have enough insulin in the body to use available glucose.

When fat is being burned because of low insulin, the body will continue releasing fat cells to the liver as long as the amount of insulin is low. If a healthy insulin level is not restored, the fat continues to metabolize and ketones are constantly pumped into circulation. As the amount of ketones becomes more toxic, symptoms of diabetic ketoacidosis (DKA) set in.

Drinking a lot of water flushes ketones from the body, but ketones will continue to be manufactured in overdrive until insulin is present to suppress production.

Ketones and Diabetes Types

Although they are less ketone vulnerable, people with type 2 diabetes (and parents of children with diabetes) should be prepared to test for ketone levels. They wisely do so:

• during an illness; the body burns more glucose when fighting disease or infection.
• when glucose readings are above 250 mg/dL.
• when they notice any signs of DKA. If someone with type 2 diabetes undergoes an increase of insulin resistance and is unaware of it, DKA is a possibility.
• if glucose levels are not being carefully managed.

DKA occurs more than two-thirds of the time in people with type 1 diabetes because their bodies do not produce enough ketone-regulating insulin. The most vulnerable are children, young adults, and those using insulin pumps. Pumps are effective glucose management tools, but a disconnect or functional failure will significantly alter blood sugar levels.

Elevated ketones can occur frequently and rise quickly in pregnant women with pre-existing or gestational diabetes. Being educated about DKA and knowing how to test for ketones are important for the health of mother and baby.

Know the Symptoms

Whatever type of diabetes you or a loved one has, have a ketone management plan prepared and know the signs of DKA: fruity smell on the breath, extreme thirst, urinating often, rapid heart beat, confusion, irritability or aggression, agitation, feeling weak or sluggish, fatigue, breathing rapidly, nausea, and vomiting.

Sources: Diabetes Healht; UCSF Diabetes Ed Online; ChemCraft; Am Diabetes Assoc
Photo credit: Kim Knoch