When you have diabetes, a chronic condition where the body struggles to manage blood sugar. Also known as hyperglycemia, it can lead to dangerous imbalances if not monitored closely. One of the most overlooked but critical checks is testing for ketones, byproducts your body makes when it burns fat instead of sugar for energy. This happens when insulin levels drop too low, especially in type 1 diabetes, but can also occur in type 2 under stress or illness.
Testing for blood ketones, a more accurate measure than urine ketones. Also known as beta-hydroxybutyrate, is something you should do when your blood sugar stays above 240 mg/dL for hours, you’re sick with the flu or an infection, or you feel nauseous, tired, or breathless. Unlike urine strips, which can be delayed or misleading, blood ketone meters give you real-time numbers—just like checking your glucose. A reading above 1.5 mmol/L means you’re at risk for diabetic ketoacidosis, a life-threatening condition where your blood becomes too acidic from excess ketones. Also known as DKA, it requires immediate medical care.
Most people with diabetes don’t test ketones regularly—until it’s too late. But checking them during illness or high blood sugar isn’t extra work; it’s a safety net. Think of it like checking your tire pressure before a long drive. You don’t do it every day, but when conditions change, you check. If your ketone level is between 0.6 and 1.5 mmol/L, drink water, take your insulin as directed, and retest in a few hours. Above 1.5? Call your doctor or head to the ER. You don’t need to panic, but you do need to act. Many emergency visits for DKA happen because people waited too long, assuming high sugar alone was the problem. It’s not. Ketones are the silent trigger.
The posts below cover real-world situations where ketone checks matter—from managing illness with diabetes to understanding how stress, missed insulin doses, or even low-carb diets can push your body into ketosis. You’ll find guides on choosing the right meter, interpreting results without confusion, and what to do when your numbers climb. These aren’t theory pieces. They’re what people actually use when they’re scared, confused, or trying to avoid a hospital trip. If you or someone you care about has diabetes, this isn’t optional knowledge. It’s the difference between managing your health and being caught off guard.
Learn the essential sick day rules for diabetes: how to manage insulin, stay hydrated, and check ketones to prevent dangerous complications like DKA. Essential guidance for Type 1 and Type 2 diabetes during illness.
