Are sugar-free drinks bad for you?

Emma Brown - Nutritionist | 23 Oct, 2015

Sugar-free drinks can be a good substitute for sugary beverages and for people who struggle to drink plain water, as they are still a good source of fluid for our body.

Sugar-free drinks are usually sweetened with artificial sweeteners, and although some of these have experienced quite a bit of flack over the years, there is no proven evidence to suggest any harmful effects. A review by the EFSA (European Safety Authority) – the body responsible for food safety in Europe – concluded that artificial sweeteners pose no risk to our health even in excessive amounts (greater than a human would ever consume). They have therefore been deemed safe for human consumption.

Some of the most common sweeteners used in food and as table top sweeteners are Acesulfame K, Aspartame, Sucralose, Sacharin, Xylitol and Stevia. All of these have been reviewed by the EFSA and have been approved for use. Many of these sweeteners aren't actually absorbed by our bodies, or if they are, they are very quickly excreted, so there is no risk of a potentially harmful accumulation in your body.

One thing to be aware of though, is that certain sweeteners which are polyols such as xylitol, sorbitol, mannitol, maltitol can have a laxative effect if consumed in large amounts. These sweetners tend to be used in foods like sugar free sweets – so ensure you only eat these in moderation.

Swapping from sugar to a low calorie sweetener is a great way to save calories and reduce the chance of consuming excess calories that can lead to weight gain. Truvia uses Stevia, a new natural sweetener which is extracted from the Stevia plant, so this is a good one to try if you want something a bit more natural.

Sweeteners and weight gain


There has been some research which suggests that having a drink sweetened with calorie-free sweetener can lead to over-eating later on in the day. The theory is that the sweet tasting drink makes our body to believe it is about to receive some calories, but then it doesn't. The processes that have kicked into gear in anticipation of food, then cause us to feel hungrier and crave something sweet – which can lead to people eating more calories in their next meal than they would have if they hadn't had the sweet tasting calorie-free drink.

However the research around artificial sweeteners and weight gain is inconclusive. Some studies have shown that replacing sugary drinks with diet versions leads to weight loss – while others have suggested those who drink large amounts of sugar-free artificially sweetened drinks tend to be more overweight than those that don't. The issue is with many of these studies, is that causality can't always be confirmed. It may just be that people who drink a lot of diet drinks are already overweight and trying to diet – not that the drinks are actually leading to weight gain.

The bottom line is that a person still has to eat too many calories in order to gain weight. The artificial sweeteners are not directly causing weight gain. Using your Nutracheck food diary you can keep track of your calorie intake and ensure you do not go over your allowance each day – whether you have a diet drink or not.

Nutritionist Emma Brown (ANutr), MSc Human Nutrition is passionate about how food science applies to the human body, and how the nutrients in what we eat affect us and ultimately have an impact on our health.