Editorial Note:
This article is an expanded and revised edition of a previously commissioned feature. It has been updated to clarify the difference between nutritional ketosis and diabetic ketoacidosis (DKA), when ketone testing matters most, and which symptoms should be treated as urgent rather than “wait and see”.
Key takeaways (quick read):
- Ketones are not automatically dangerous, but high ketones with high glucose can signal an emergency.
- Illness is a trigger: being unwell can raise both glucose and ketones quickly, especially in Type 1 diabetes.
- Testing changes decisions: ketone checks help you act earlier (fluids, insulin plan, medical review) rather than reacting late.
Quick action today: if you are at risk of DKA, keep ketone strips/meters available and know your “when to test” triggers (illness, high readings, vomiting).
Managing diabetes involves constant vigilance over blood sugar levels, insulin usage, and overall health. One crucial aspect of diabetes care that is often overlooked is understanding ketones—byproducts of fat breakdown in the body. Whilst ketones are a natural and necessary part of metabolism, for people with diabetes, they can become a sign of serious trouble if not managed properly. Understanding ketones is key to managing diabetes effectively and avoiding life-threatening complications.
What Are Ketones?
Ketones are chemicals produced when the body burns fat for energy. Normally, the body uses glucose (sugar) from carbohydrates as its primary energy source. However, when glucose is unavailable or insulin isn’t functioning properly, such as in diabetes, the body switches to burning fat. This process leads to the production of ketones, which can be used by the brain and muscles as an alternative energy source.
Whilst ketones are a normal part of metabolism, they can become problematic when they accumulate in high concentrations. This can be particularly dangerous for individuals with type 1 diabetes and, to a lesser extent, those with type 2 diabetes.
The Risk of Diabetic Ketoacidosis (DKA)
The most significant reason to understand ketones in diabetes management is to prevent diabetic ketoacidosis (DKA). DKA is a potentially life-threatening condition that occurs when ketones build up to dangerous levels in the blood, causing it to become acidic. DKA happens when the body lacks enough insulin to process glucose properly, prompting the body to break down fat rapidly. The resulting ketones accumulate to harmful levels.
DKA can develop rapidly, often without obvious symptoms at first, and it requires urgent medical attention. If untreated, it can lead to coma or even death. Whilst DKA is more common in individuals with type 1 diabetes, it can also affect those with type 2 diabetes, particularly if their blood sugar levels are poorly controlled, during illness, or under significant stress.
Symptoms of DKA include excessive thirst, frequent urination, nausea, fruity-smelling breath, and fatigue. If these symptoms arise, it’s essential to seek medical help immediately to avoid severe complications.
The Role of Ketone Monitoring in Diabetes
Monitoring ketones is a critical aspect of managing diabetes. While blood glucose monitoring is standard practice, ketone testing can offer valuable insights, especially during illness, stress, or periods of high blood sugar. Regular ketone checks allow individuals with diabetes to catch the early signs of DKA before it becomes a severe emergency.
There are two common ways to test for ketones: urine test strips and blood ketone meters. Urine strips are an affordable option that change colour based on the concentration of ketones in the urine. Although they are easy to use, they are less accurate than blood ketone meters, which provide a more precise reading of blood ketone levels. Whilst urine tests can be useful for general monitoring, blood ketone meters are a better choice for individuals at higher risk of DKA or those who need more accurate readings.
Knowing when to check ketones is just as important as the method of testing. For people with diabetes, it’s essential to monitor ketones during periods of elevated blood sugar, particularly when blood glucose is over 250 mg/dL. Illness and stress also increase the likelihood of higher blood sugar and ketones, so monitoring during these times is crucial.
Managing Ketones and Preventing DKA
While testing for ketones is essential, the key to keeping them at safe levels lies in prevention. The most effective way to manage ketones is to maintain proper insulin use. Insulin allows the body to use glucose for energy, preventing the breakdown of fat and the production of ketones. Adjusting insulin dosages, particularly during times of illness or stress, can help prevent the onset of DKA.
Staying hydrated is another vital preventive measure. Drinking water helps flush ketones from the body, reducing the risk of them building up to dangerous levels. Dehydration can exacerbate the effects of high ketones, so adequate fluid intake is essential.
Monitoring blood glucose levels regularly is also an important strategy in preventing high ketone levels. If blood glucose levels rise too high, there’s a greater chance that ketones will form. By staying on top of blood sugar levels and adjusting insulin doses as needed, individuals with diabetes can avoid the conditions that lead to elevated ketones.
Additionally, it’s crucial to seek medical advice if symptoms of DKA arise or if ketone levels are high. Early intervention can prevent complications and help individuals manage their diabetes more effectively.
Understanding Ketones for Better Diabetes Management
In conclusion, understanding ketones is essential for anyone managing diabetes. Whether someone has type 1 or type 2 diabetes, being aware of how ketones form and knowing how to monitor and manage them can make a significant difference in preventing dangerous complications like DKA.
By regularly monitoring ketone levels, using insulin properly, staying hydrated, and recognising the signs of high ketones, individuals with diabetes can take control of their health and reduce their risk of severe complications. Awareness and early intervention are crucial to ensuring better overall diabetes management and maintaining a healthier, more fulfilling life.
Ketones in Real Life: When to Test, What It Might Mean, and When to Get Help
Ketones are a normal byproduct of fat metabolism, and small amounts can appear for many reasons (including fasting or lower-carbohydrate eating). The key concern in diabetes management is recognising the pattern that can signal DKA risk, and acting early.
Ketosis vs DKA (simple distinction)
- Nutritional ketosis: can occur with fasting or low-carb diets; often lower ketone levels and not automatically dangerous.
- DKA risk pattern: ketones rising because the body lacks effective insulin, often alongside high glucose and dehydration.
When ketone testing is especially important
- When you are ill (fever, infection, vomiting/diarrhoea), even if you are eating less than usual.
- When glucose is persistently high despite following your usual plan.
- When you have nausea, vomiting, or abdominal pain, especially with fatigue or rapid breathing.
- When you suspect missed insulin or pump/pen delivery issues.
Urine strips vs blood ketone meters (practical pros/cons)
- Urine strips: more affordable and accessible, but can lag behind real-time changes.
- Blood ketone meters: more precise and timely, often preferred for people at higher risk or during illness.
Red flags: do not delay medical attention
Seek urgent medical care if there is persistent vomiting, inability to keep fluids down, fruity breath, rapid/deep breathing, severe weakness, confusion, or drowsiness—particularly if glucose is high and ketones are present. DKA can progress quickly and requires prompt treatment.
A calmer “what to do next” checklist (non-emergency situations)
- Hydrate: sip water regularly (or as advised if you have fluid restrictions).
- Re-check: repeat glucose/ketones at an interval advised by your clinician to see direction of travel.
- Follow your sick-day plan: if you have one, use it (including insulin adjustments if prescribed).
- Escalate early: contact a healthcare professional if ketones are rising, you feel worse, or you are unsure.
Frequently asked questions
Can people with Type 2 diabetes get DKA?
Yes, although it is more common in Type 1 diabetes. Risk can increase with illness, dehydration, very high glucose, or certain situations where insulin is insufficient.
If I see ketones, should I panic?
Not automatically. The context matters (how you feel, glucose level, illness). Treat it as a prompt to monitor closely and follow medical guidance—especially if unwell.
Medical note: This article is for general education and is not a substitute for medical advice. If you have Type 1 diabetes, are pregnant, are on insulin, use an insulin pump, or are unwell with high glucose/ketones, seek personalised guidance and urgent care when indicated.
Editorial update: 22 February 2026 — expanded with ketosis vs DKA clarity, testing triggers, tool comparisons, and red-flag guidance.
Note: This piece was written as a commissioned feature and has appeared in other health and lifestyle platforms.