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Ketones and Blood Sugars



I`m type 1, I use an insulin pump.

Is the only time ketones are dangerous is when the blood sugars are high? I`ve never been in DKA(although I`m well aquanted with ketones, I`m some what DKA resistant) Sometimes when I get a stomach “bug”, my only problem is extreme nausea and not being able to get rid of the ketones.(ranging from small-large urine ketones) I know these are starvation ketones-if they stick around for awhile, does that mean one is losing weight(at an unsafe rate)?

What I`m wondering it ok for a type 1 to have ketones if their blood sugars aren`t high?

Thank you.


Insulin is the “key” that allows glucose into our cells for energy.We need energy 24 hours a day, every minute of the day. Even if we eat zero carbohydrates for a whole day, our bodies need a constant supply of insulin.

If we don’t have enough insulin, then our bodies can’t get enough energy. We start breaking down fat and muscle for energy. When fat and muscle are burned for energy, ketones are produced. Ketones (the term we use loosely to describe the keto-acids acetoacetic acid and beta-hydroxy-butyric acid) – are a breakdown product of fat which is dangerous when present in excess in the body – and can be dangerous even in people without diabetes. It is never “OK” for a person with Type 1 diabetes to have ketones. It is important to distinguish between the significance of ketones in somebody with type 1 diabetes versus in someone without diabetes. If a nondiabetic person goes for a “long enough” period of time without food, they will produce less insulin than normal for them and it would not be surprising if modest levels of ketones appear in the blood. However, in somebody with type 1 diabetes, the presence of ketones signifies a dangerously low level of insulin.

Like the “low fuel” light on your car means you are almost out of gas, ketones mean you are almost out of insulin. Normally it takes VERY LITTLE insulin to turn off ketone production. Although blood glucose levels are usually high if you have ketones, the ketones are not caused by high blood glucose levels. Ketones tell us about the insulin level in the blood. In most cases, blood glucose levels are high when people have ketones. But ketones may be present with a normal blood glucose level.

Ketones are a sign that our bodies are not getting enough energy from glucose. If we are not getting enough energy, lactic acid can build up in our tissues and in the blood. Ketones are also an acid; the more ketones in the blood, the more acid in the blood. Too much acid in the blood is VERY dangerous, it can cause coma and death. Always check ketones if your blood glucose is high, or if you are nauseated or vomiting.

If you are vomiting or have ketones, follow the ketone guidelines you’ve received from your diabetes care provider. The treatment for ketones is insulin. When you have ketones, you need to take a blood glucose correction bolus (if your blood glucose is high) and also take a “ketone bolus” or extra insulin for the ketones. Ketones make our bodies resistant to insulin, therefore extra insulin is needed. In most cases, you need to take extra insulin for ketones, even if your blood glucose level is not high. Your diabetes care provider will tell you how much extra insulin to take for ketones.

When you have ketones and high blood glucose levels – ALWAYS take blood glucose correction and ketone insulin doses by INJECTION, not by the insulin pump. The most common cause for ketones in pumpers is a bad infusion set. Therefore do not give the correction and ketone doses by pump when you have ketones – you need to ensure that you are getting this insulin. Change your infusion set as soon as possible, even if you recently inserted a new infusion set. Check your tubing for air, and make sure there is insulin in the cartridge or reservoir. If the insulin has been in the cartridge or reservoir more than 24 hours, or if you have recently exposed the insulin to changes in temperature or motion, then change the insulin also.

Other possible causes of ketones in pumpers are 1) lipohypertrophy at pump infusion set sites (caused by using the same sites over and over, so the insulin does not absorb well), 2) using insulin that has lost potency (for example, the insulin is old or has lost potency by exposure to motion or changes in temperature), or 3) illness (illness increases the body’s need for insulin). All of the above can result in low insulin levels in the blood, and ketones.

If blood glucose levels are high and ketones are present at the beginning of a vomiting episode – then you can assume the vomiting is caused by the ketones, not by illness. If blood glucose levels are not high and ketones are negative at the start of a vomiting episode, then the vomiting is more likely to be caused by illness or gastrointestinal disturbance.

Vomiting with ketones can be extremely dangerous because acid levels in the blood can become dangerously high. If you are vomiting with ketones, call your diabetes care provider. You should not be alone – call a family member or friend to stay with you, and be available to bring you to the hospital if necessary.

Why would a person with Type 1 diabetes have ketones when their blood glucose levels are not high? First of all – be sure that you are defining “high blood glucose level” appropriately. The blood glucose goal range for most adults with Type 1 diabetes is 70-150 mg/dl. Therefore anything above 150 mg/dl is usually considered “high”. Talk with your diabetes care provider and identify your target blood glucose goal range.

Although ketones without high blood glucose levels is less dangerous than if the blood glucose levels are high – it is still a cause for concern. If you have a blood glucose level under 150 mg/dl and have ketones – we need to look for reasons for low insulin levels in the blood. The most likely cause is that the person is not eating carbohydrates regularly – and so does not bolus much insulin each day for carbohydrates.

Our bodies depend on a certain amount of insulin every day. If the total insulin dose is too low, ketones are produced. People with Type 1 diabetes should eat carbohydrate-containing foods and bolus with insulin at least three times a day, spaced throughout the day. For most people, the total amount of basal insulin received in a day does not exceed 60% of the total daily dose of insulin. This means at least 40% of the total daily dose of insulin comes from bolusing for carbohydrates.

Remember – carbohydrates are not “bad” for people with Type 1 diabetes. To maintain a healthy weight, we need to match the calories that are eaten (in carbohydrates and other foods) with exercise that burns calories. As long as we match “calories in” with “calories out” – we will maintain a healthy weight.

Related Resources:

Children with diabetes
American Diabetes Association

For more information:

Go to the Diabetes health topic.