The impact of sports drinks on blood glucose

Lynette Lacock looks at the impact of sports drinks on blood glucose levels in people with diabetes and offers healthier alternatives.

The origin of sports drinks

Sports drinks have been around since the early 1900s. One of the first commercially successful drink was Lucozade which was launched in the UK in 1927. Originally it was sold by a pharmaceutical company and primarily marketed to sick people. Today we have a large variety of sports drinks marketed to healthy active people. In fact, globally it is a (USD) $26 billion industry.

These drinks are designed to replace fluids and electrolytes that are lost while exercising. They mostly contain water, sugar (carbohydrate), minerals, electrolytes, vitamins and some also include caffeine.

What do they do for you?

During periods of intense exercise, you lose water and electrolytes.  Both of these are essential for your muscles to work properly. When you exercise for long periods of time, your body turns carbohydrates into glucose that your body uses as fuel. If your glycogen (glucose) storage gets low, you will become tired and not be able to perform optimally.

Using energy drinks can help hydrate you and provide your body with an energy source. However, these drinks contain an average of nine teaspoons of sugar per helping. So, if you have diabetes, this high amount of sugar can cause your blood glucose to spike.

Do you need the added caffeine?

Many energy drinks on the market contain caffeine as well as carbohydrates and electrolytes. The reason behind this is that caffeine has been shown to stimulate your brain by increasing focus, concentration and reaction time. The goal being to enhance your sporting performance.

The amount of added caffeine may be well-tolerated by a healthy adult but can spike blood glucose levels in someone with diabetes. The caffeine causes your blood glucose to rise followed by a spike in blood insulin levels. Caffeine can stay in your system for up to six hours prolonging this response in the body and causing havoc with your glucose metabolism.

Consuming sugary drinks with caffeine on a regular basis can put you at an increased metabolic risk and excessive caffeine should be avoided altogether in children, adolescents and people living with diabetes.

Do people with diabetes need sports drinks when they exercise?

As you exercise, your body becomes more dehydrated and blood glucose rises as your bloodstream becomes more concentrated. Adding carbohydrates will elevate your blood glucose even more.

If your drink also contains caffeine, it will make your blood glucose level rise even higher, requiring more insulin to bring your blood glucose levels back to normal. Overall, consuming these drinks when you have diabetes makes regulating your blood glucose very difficult.

So, to answer the question: no, people living with diabetes don’t need to consume sports drinks when they exercise. You need to look for a healthier alternative that hydrates and replaces electrolytes.

First and foremost, you must stay hydrated by drinking enough water. If you are exercising in the heat and sweating for more than one hour, you may want to replace lost electrolytes as well.

Everyone’s blood glucose reacts differently to various types of exercise and to monitor yourself effectively you need to be drinking sugar-free and caffeine-free drinks. Always check with your doctor before starting a new exercise regime and follow the tips below to see how your body reacts to the increased activity.

Monitoring tips when exercising

  • Check your blood glucose before, during and after exercising.
  • The first couple times you start a new exercise, check your blood glucose two, four and six hours after exercising because it can cause your blood glucose to drop, requiring you to eat more or lower your evening insulin dose.
  • Keep a carbohydrate snack on hand in case you experience a hypoglycaemia attack while you are exercising.
  • Drink plenty of water to remain hydrated while you exercise.

Healthy alternative drinks for people with diabetes

Sports drinks companies have already come out with sugar-free and low sugar alternatives. For example, Energade Light and Powerade Zero contain little or no extra sugar or caffeine but still contain electrolytes.

Unfortunately, most contain artificial sweeteners which don’t raise your blood glucose but do have other risk factors.  If you want to avoid artificial sweeteners, there are healthier alternatives. You could drink some of the following:

  • Unsweetened coconut milk (contains electrolytes).
  • Unsweetened fruit juices diluted with water (contains electrolytes).
  • Vegetable juice (contains electrolytes).
  • Kombucha (contains electrolytes).
  • Unsweetened tea.

You could also eat something that contains electrolytes and drink water. For example, a banana has electrolytes and you stay hydrated by drinking water.

There are other healthy sugar-free alternatives on the market. Ask your doctor or pharmacist which one is best for you.


Sr Lynette Lacock


Sr Lynette Lacock received her Bachelor’s Degree in Nursing and Biofeedback Certification in Neurofeedback in the US. She has over 30 years’ experience in healthcare which has enabled her to work in the US, UK and South Africa. Initially specialising in Cardiothoracic and Neurological ICU, she now works as an Occupational Health Sister. She is passionate about teaching people how to obtain optimum health while living with chronic conditions.

Header image by Adobe Stock