Nanogirl Michelle Dickinson: Are diet drinks a healthier choice?

Artificial sweeteners have been promoted as a solution to help with weight loss, reducing the overall calorie intake. Photo / File

COMMENT: With the arrival of the New Year, many resolutions will have been made to eat more healthily – and many of those will involve reducing the amount processed sugar consumed.

One popular and easy way to do this is – if you drink soft drinks regularly – is to buy the so-called diet drinks, which use artificial sweeteners, replacing the sugar while still satisfying a sweet tooth. Over the years, safety concerns regarding artificial sweeteners have been raised. New research out this week, however, finds they might not be as bad - or indeed as good - as we have previously thought.

Artificial sweeteners – like products including saccharin, aspartame and sucralose - have been promoted as a solution to help with weight loss, reducing the overall calorie intake. If you consider that an average can of fizzy soda sweetened with sugar delivers 150 calories - whereas an artificially sweetened diet version delivers zero calories - it's easy to see why many calorie counters make the switch.

Critics of artificial sweeteners have said that they are dangerous, and cited them as a cause of a variety of health problems, including cancer. This is fuelled by studies carried out in the 1970s that linked saccharin consumption to bladder cancer in laboratory rats. Further studies have found, however, that there is no scientific evidence that any of the common artificial sweeteners used in our foods cause cancer or other serious health problems.

Over decades of research there have been a number of similarly conflicting studies on the health effects of artificial sweetener. Some have reported as association between artificial sweetener intake and a reduced risk of type 2 diabetes, being overweight and obesity. Other studies have suggested that these same sweeteners could increase the risk of diabetes, of being overweight, and cancer.

The challenge with individual research studies is that they tend to involve a small controlled group with very few variables, so the conclusions can only be applied to a specific context. This is how one study can give the opposite result to another - and further, the specific constraints of the study often make it difficult to compare one set of data to another.

To try to overcome this, researchers from Germany identified and classified more than 13,000 peer reviewed scientific studies looking into the effects of artificial sweeteners. After analysing them, they took a deep look into the results of 56 studies that had variables which allowed the results to be compared. The studies involved controlled trials looking into the health outcomes of volunteers who had either no or low intake of artificial sweeteners to volunteers with a higher intake.

Their results, published this week in the journal BMJ, found no convincing evidence that the consumption of artificial sweeteners had any negative effect on the risk of cancer, cardiovascular disease, kidney disease, mood or behaviour when compared with those who did not consume the products. That sounds like great news for those using sweeteners for a healthier lifestyle – but wait, there's more!

Sadly, the researchers also found there was only a slight benefit in consuming artificial sweeteners when it comes to weight loss and improving blood glucose levels. If switching to artificial sweeteners was your one big lifestyle change to drop the kilos this year, the science says it probably won't help.

So, in summary, the study found no evidence of harm from consuming artificial sweeteners - but also found very little health benefit.

It seems that rather than switch to a diet soda to help kick start your new year's goal, it might be cheaper and healthier to switch to water instead.