Using fat for energy and making ketones can be a good thing. This is a normal and healthy process (called ketosis) needed in situations where we cannot eat. If you are fasting (for a religious holiday or other reason), ill or do not have access to food, you need to be able to use stored fat as food. However, the process must be regulated by enough insulin.

Runaway ketones...

A problem develops when you do not have enough insulin to regulate ketone production properly. Either you are truly starving or you do not have enough insulin in your body for some other reason.

Producing too many ketones, too quickly, is bad news. It upsets the delicate balance of body chemistry and can lead to a state called diabetic ketoacidosis (DKA) - and that is dangerous.

The good news is that you can usually prevent this from happening! Learn the 3 Rs - Risk, Recognize and React!

Risk – Know when you may be at risk for ketoacidosis.

One risk situation for all people with diabetes is when they are really ill with an infection or acute illness. The stress hormones made to fight the infection will trigger the ketosis process. People with Type 1 diabetes are particularly at risk here. Usually people with Type 2 diabetes have enough insulin to cope. However, they may also develop ketoacidosis if the stress of an acute illness or infection overwhelms their ability to produce insulin.

The other risk situation is when insulin has been missed for several hours in a person with Type 1 diabetes. An insulin injection may have been forgotten or insulin pump delivery may have been interrupted. This may allow enough time for ketosis to start. First, check for ketones and then react appropriately. (Note: exercising when excess ketones are present will not lower blood glucose. Insulin is needed first.)

Recognize - Spot the signs and symptoms of early ketosis before it becomes DKA.

Since there is little insulin, blood glucose is usually also high. There will usually be

excess thirst, passing urine, shortness of breath – and dehydration
nausea or vomiting and abdominal pain
‘fruity’ smelling breath

As the ketone level rises, the blood becomes more acidic. Dehydration combined with the acidic blood causes DKA.

Urine versus blood: testing for ketones

The best way to know if ketones are above normal levels is to check blood or urine ketones, rather than waiting for the symptoms to appear. The more common method of checking for ketones is to dip a urine ketone test strip into a fresh urine sample. After a specified time the colour of the strip is checked against the colour gradient on the side of the ketone test strip package. Different colours indicate small, moderate or large amounts of ketones present in the urine. This reflects the levels of ketones in the blood hours earlier. A more timely method of checking is to test the blood for ketones. With new technology, ketones can be checked with strips and a testing machine. Ask your pharmacist for more information.

The guidelines for testing for ketones are changing. As the resources for book ketone testing becomes more widely available, blood ketone testing may replace urine ketone testing.

React – Recommendations for testing are intended to help you recognize early signs or symptoms and treat them early.

Prevent DKA! All people with diabetes, especially those with Type 1 diabetes, should know to test their blood or urine ketones in the following situations.

They are sick with an infection or flu
They are under severe stress, either emotionally or physically
Their blood sugar is consistently over 16.0 mmol/L, without a known reason, or as their doctor has recommended
They have any of the symptoms of ketoacidosis

If you do become ill, follow these Sick Day Management guidelines.

Always take your insulin or other diabetes medication, even when you are unable to eat as usual. You may need to take more insulin. Do not omit doses, even if you are not eating as usual.
Check your blood glucose and ketone levels every two to four hours around the clock. If blood ketones are >0.6 mmol/L or urine ketones are moderate to large, follow your sick day guidelines for adjusting insulin. Work with your doctor or diabetes educator to develop personal sick day guidelines.
If your sugars are high (e.g. >16.0 mmol/L) and you have excess ketones, you will need more insulin. Call your health professional for advice or follow your dose adjustment guidelines.
Call your doctor or go to the emergency room if you are vomiting, have blood ketones >3.0 mmol/L, or are showing moderate to large levels through a urine test. If you are unable to eat, drink sugar-containing fluids to replace food with fluids. Try to take in 10 grams of carbohydrate every hour, e.g. 1⁄2 cup regular pop, 1⁄3 cup apple juice, 1⁄4 cup regular Jell-O™ or sherbet.

An ounce of prevention is worth a pound of cure, especially when it comes to DKA. If your blood glucose is generally in good control, ketosis should be a rare thing. But remember the three Rs of ketones: know your risk, recognize early symptoms, and react quickly.

Urine versus Blood - Testing for Ketones

	PROS	CONS
Blood	measures the ketones found in the greatest quantity results not affected by medications or vitamin C provides current information required for early detection and monitoring of DKA strip packaging resistant to effects of moisture and heat familiar testing procedure	requires a particular blood glucose machine strips are more expensive may require a second finger poke foil strips sometimes difficult to open
Urine	strips are inexpensive doesn't require a blood glucose machine currently recommended by the Canadian Diabetes Association finger poke not required strips are packaged in easy-to-open bottles	can be messy those with visual difficulties may have problems reading strip results are not timely test results affected by some medications and vitamin C not adequate for diagnosing or monitoring DKA strips sensitive to moisture and temperature and expire quickly once opened