Diet drinks can be a very convenient option for those looking to kill a craving, enjoy a soft drink in the sun, and reduce caloric intake. And look at what we are replacing;
1 litre of
sugar-sweetened beverages can sometimes contain 100g sugar or more. Given that this 400 calories of sugar contains no fibre, little additional nutrition, and no physical eating, you are left without much satiation and thus very likely to over-consume calories.
Not if it's 'zero', however...
But, is it really this simple, or do these sweeteners cause as much or more harm than the sugar would have?! To answer this, we need to compare the thresholds of harm for commonly used sweeteners with the quantities contained in zero-calorie soft drinks.
One of the most frequent sweeteners of concern is Aspartame.
Aspartame may indeed be harmful for humans, with the upper limit of safe intake set at 40mg per kg. Personally, when I see a "safe upper limit", I'd rather stay quite shy of that, rather than pushing the line. So, what does this look like in practice?
As we can see, most people are probably well below the upper limit of safety set, provided you are consuming < 10 cans per day. 9-14 cans per day may lead to a 70kg individual exceeding the acceptable daily intake,
depending on the quantity of aspartame in the drink. Most health-conscious individuals have no more than 1-3 cans per day, so thus this is unlikely a concern for most.
Also consider other foods that may contribute aspartame, e.g. sugar-free syrups, food products, etc. If you are using lots of these products alongside very heavy sweetened beverage consumption, you
may run into the threshold at which risks may be elevated. We just don't have great evidence on this question overall, so I think we should be reasonable in our conclusions.
1.) Aspartame and other non-nutritive sweeteners may carry some harm, such as increasing cancer risk, but this seems to be beyond current average consumption. Nonetheless, moderating intake is
probably best, and water remains your best choice.
2.) The risks of high sugar intake and overconsumption of calories are likely worse than any risks attributable to such sweeteners, so where there is a choice between the two, the non-nutritive sweetener option (e.g. aspartame) is probably better.
3.) Consideration of other risks attributable to such soft drinks, such as tooth decay, is also important. Acidic soft drinks may still precipitate tooth decay, although it's best to consult with a dental professional on matters of dental health, as this is not our area of expertise.
4.) For the
person seeking "optimal" and looking to minimise all nutrition-related risks to health, the precautionary principle would suggest it is reasonable to avoid non-nutritive sweeteners and stick to water. Most people don't tend to fall into this bracket.
If you have any further questions, feel free to ask!
