ALCOHOL, SMOKING, VAPING & SUBSTANCE USE
What’s worth knowing when these things come up, and why diabetes makes the stakes a little higher.
Questions about alcohol, smoking, vaping, or substance use are normal as you get older. If you live with diabetes, there are a few extra things to think about, because all of them can affect your blood sugar and your overall health.
Alcohol Basics
Why alcohol affects diabetes differently.
🍷 Why alcohol lowers your blood sugar
Drinking alcohol lowers your blood sugar levels because your liver is busy breaking down alcohol instead of releasing glucose. This means you can still have low blood sugar hours after your last drink.
⚠️ What to watch out for
Severe lows can look like being drunk
Confusion, slurred speech, poor coordination, and sleepiness are signs of severe hypoglycemia, but they look exactly like being drunk. Don’t go to sleep alone after drinking without telling someone.
Alcohol also makes it harder to notice a low yourself
It is not only other people who can miss it. Alcohol dulls your own warning signs, so you may not recognise a low as quickly as you would sober.
Vomiting after drinking can lead to DKA
If you ever drink so much that you vomit, the vomiting and dehydration can cause diabetic ketoacidosis (DKA), which is a medical emergency.
To Stay As Safe As Possible
If you do drink, a few things help.
💧 Drink water before alcohol
You won’t be as thirsty and you’ll likely drink less.
🍺 Pace yourself
Sip slowly. Know what counts as “one drink” for what you’re drinking, a strong cocktail can equal 2–3 drinks even if it looks like one.
🚫 Don’t binge drink
Not more than 4 standard drinks, and remember a cocktail can already count as 2–3 of them.
🥨 Eat carbs before drinking
A meal with carbs before drinking helps protect against lows.
🗣️ Let someone know
Tell at least one person you are out with that you have diabetes and how to help in an emergency. If you are out without friends, carry an ID that states your diagnosis.
📱 Know what’s in your drink
Beer, sweet wine, and liquors contain carbs, and there’s no single rule on how to handle them. Some experts recommend not including the carbs of alcoholic drinks in your calculations because alcohol blocks your liver from releasing glucose, which can cause dangerous lows (see Breakthrough T1D Australia). Others suggest including the carbs to some extent, with very careful dosing (see Breakthrough T1D US). Ask your medical team what they recommend for you, this is a question worth bringing up before you’re in the situation.
🌙 Test before bed
Aim for above 150 mg/dL, alcohol can cause delayed lows hours later. If you’re below 150, have a snack with carbs and protein.
Remember
Less is better, and not drinking is safest.
🌍 Legal drinking ages
These vary by country and can change over time. A few examples:
- U.S., 21
- Canada, 18 or 19, depending on province
- Australia, 18
- UK & European countries, rules vary; some allow beer or wine at 16 or 17 if with an adult
Always check the current rules where you live or are traveling.
Smoking & Vaping
Both carry serious health risks, and diabetes raises them.
🚭 General health risks
Lung cancer and other cancers, heart disease, stroke, kidney disease, and atherosclerosis (hardened arteries).
📈 With diabetes the risks are higher
Nicotine makes blood sugar rise, makes it harder for insulin to work, and creates insulin resistance. These problems happen with regular cigarettes and vapes.
💨 Vaping is not harmless
It still contains nicotine, plus chemicals whose long-term effects on the lungs are still being studied. Vaping has been linked to serious lung injury, and nicotine in any form (vape or cigarette) makes diabetes harder to manage.
Substance Use
Why drugs are especially risky when you have diabetes.
⛔ A reminder
Illegal drugs are against the law at any age. In the U.S., alcohol, tobacco and vaping are for 21 and over, and so is cannabis in the states where it is legal at all. The information below is about diabetes-specific risks, not encouragement.
🧠 Drugs affect everyone, diabetes raises the stakes
Drugs come with serious health and mental health risks for anyone, and the risks are even greater when you have diabetes.
⚠️ Routine slips happen
Drugs make it more likely you’ll forget to check your blood sugar or take insulin, which can lead to very low or very high blood sugar.
🛑 Long-term harm is real
Regular drug use puts you at higher risk of severe health problems and even death.
💊 Specific risks worth knowing
Stimulants can mask the warning signs of a low. Substances that dehydrate you (like ecstasy) raise the risk of DKA. Cannabis can disrupt eating and blood sugar tracking. The interactions are real, and they can make a bad situation much worse.
📌 Before you go
TeenHealthInsight is a health education website, not a substitute for medical advice. Any questions or worries about your medication, devices, or daily care should be brought to your doctor. Learn here, decide there, always loop in your diabetes team before changing anything you do.