School holidays are peak travel season. For people living with diabetes, a little preparation goes a long way toward a safe and enjoyable trip.
Dr Cho Li Wei, Consultant Endocrinologist at LW Cho Endocrine Clinic, spoke to Lianhe Zaobao about the health problems diabetic travellers most often face, and how to prepare for them.
Common health problems when travelling with diabetes
- Blood sugar swings. Low blood sugar can follow delayed meals (such as late in-flight meals), more activity than usual, or a time zone change; people on insulin need extra care. High blood sugar can come from travel stress, irregular meals, or unfamiliar local dishes with hidden sugar. If your body is still “asleep” when a meal arrives after crossing time zones, it may not process the carbohydrates well and blood sugar can spike. In the worst cases this leads to diabetic ketoacidosis (DKA), especially if extreme temperatures cause insulin or an insulin pump to fail.
- Stomach upsets. People with diabetes are at higher risk of traveller’s diarrhoea from contaminated food or water, which can cause low blood sugar and dehydration.
- Respiratory infections. These are more common in people with diabetes, so get the recommended vaccinations, such as influenza and pneumococcal, before you go.
- Foot and circulation problems. Holidays mean more walking, and more blisters, cuts and scrapes. With nerve damage (neuropathy), an injury can go unnoticed and quickly become a serious infection. Long-haul flights also raise the risk of blood clots.
- Dehydration. Hot weather makes dehydration more likely, which pushes blood sugar up. In severe cases it can lead to hyperosmolar hyperglycaemic state (HHS), a potentially fatal condition whose symptoms include confusion.
How time zones, temperature and stress affect blood sugar
Temperature. Heat or cold, such as a freezing checked-baggage hold, can damage insulin and blood glucose test strips.
Time zones. Flying east shortens your day, so doses come closer together and the risk of low blood sugar rises. Flying west lengthens your day; if doses are spaced further apart, the risk of high blood sugar rises. If you cross five or more time zones, your doctor may need to adjust your medication.
Stress and sleep. Too little sleep or more stress than usual triggers the stress hormone cortisol. Cortisol prompts the liver to make glucose, which raises blood sugar.
Before you go: a diabetes travel checklist
- See your doctor before departure to plan your medication schedule.
- Wear a watch set to Singapore time so you don’t mix up dose times.
- Check your blood sugar regularly during flights, and carry fast-acting sugar such as juice or glucose tablets.
- Ask your doctor for a memo listing your diagnosis and all medicines and supplies you carry (insulin, syringes, glucose monitors).
- Pack extra medication and supplies in your carry-on bag, away from the cold hold and safe if luggage goes missing.
- Buy travel insurance that covers pre-existing conditions such as diabetes. Ordinary policies may not, and emergency care abroad can be very costly. Dr Cho once had a patient hospitalised overseas with HHS.
- Find out which hospitals or clinics near your hotel treat diabetes.
- Wear a medical ID bracelet or carry a card in the local language that says “I have diabetes”.
Plan ahead, check regularly
Dr Cho’s advice comes down to two habits: plan ahead and check regularly. Don’t rely on guesswork; test to know where your blood sugar stands. Travel stress, unfamiliar food and uneven activity all make blood sugar harder to predict, so monitor more often than usual for the first 48 hours in a new time zone.
Planning a trip and unsure how to adjust your insulin or medication across time zones? Our team at LW Cho Endocrine Clinic can help you prepare, so book an appointment before you go.
This article is for general information and does not replace personalised medical advice.
Adapted from Lianhe Zaobao, 16 June 2026 (read the feature in Chinese).
