Artificial sweeteners (or non-nutritive sweeteners) provide a zero-calorie alternative to foods and beverages, while still giving them a sweet taste. Seems like a no brainer right? Enjoying your favourite sweet food and drinks without the consequences. But the jury is still very much divided on whether these chemicals are completely harmless in the long-term. We now know they aren’t dangerous to our health in the short-term, but I do have a few issues with reliance on them and the frequent consumption of these artificial compounds in terms of optimal health and wellbeing.
There are lots of different types of artificial sweeteners and they are used in a wide range of different products. Most commonly, artificial sweeteners are used by those looking to lose weight. Replacing refined sugar with artificial sweeteners in your diet can be an effective way to dramatically lower their overall calorie intake whilst continuing to consume the foods you enjoy. There is some promising research on this topic and studies have demonstrated that an adjustment from regular to artificially sweetened may help to reduce obesity, diabetes mellitus, and similar problems. Benefits in dental health have also been observed in those switching from regular sugar to artificial sweeteners. But while some studies have found positive effects on weight from artificial sweeteners, some haven’t.
The majority of short and long term studies on humans have found that consuming artificial sweeteners doesn’t appear to decrease dieters overall energy intake, but randomised trials have found people who switch from regular sugar to artificial sweeteners can successfully reduce both their body weight and fat. We can’t ignore the fact that artificial sweeteners encourage sugar cravings and sugar dependence because they are, well, sweet. We know that repeated exposure trains flavour preference, thus the more we expose our taste-buds to sweet things, the more we want them. Which is a preference that doesn’t typically favour healthy habits and food choices. So while you might be reducing your drinkable energy intake, you are more likely to seek out other sweet, high-energy, low-nutrient dense foods as a whole. Which is one possible explanation for why there is sufficient research suggesting an association between people drinking diet drinks and obesity.
Another area of research on the topic of artificial sweeteners and weight that doesn’t look quite so sweet is the consumption of artificial sweeteners in pregnancy and offspring obesity risk. While there are a lot of other factors (family history, environment, socioeconomic status, other dietary factors etc) to consider when it comes to this research the evidence we have demonstrates that daily artificial sweetener consumption in pregnancy increases the incidence of childhood obesity by aged 7 years, compared to children from mothers who did not consume artificial sweeteners.
There are still many people who hear 'artificial sweeteners' or 'aspartame' and think of cancer risk. The FDA approved the use of aspartame in 1974 following a substantial amount of evidence gathered from labs and clinics around the world, declaring it was safe for use in food and beverages. But in the early 2000s, a group of scientists conducted a few studies in on rodents which found that exposure to aspartame was associated with multiple cancers in mice and rats. This quite rightly resulted in us all taking a closer look at the safety of artificial sweeteners. The research has now been picked apart as the doses of artificial sweeteners used in the rodent trials were far higher than what could be physically consumed through daily beverages consumption. While many people still argue that we don't have enough research on the effects of artificial sweeteners to deem them 'safe', as of today we don't currently have any solid research to support an increased cancer risk from artificial sweeteners at regular consumption levels.
Although we don’t have any solid cancer evidence, we do however have some interesting evidence demonstrating the possibility for other less serious, yet still negative effects health effects. Here’s a quick summary of what we currently have:
The gut microbiome - artificial sweeteners have shown the potential to both change the good bacteria in the gut and potentially kill them (particularly Sucralose).
Blood sugar - evidence shows that artificial sweeteners can interact with the microbes in the gut which may lead to increases in blood sugar.
IBS - sugar alcohols can cause digestive discomfort such as bloating, gas and diarrhoea. So if you struggle with IBS, you are probably best steering clear.
BPA - we know that BPA (an environmental chemical that is found in plastics and cans) has adverse effects on health and has been associated with an increased risk of obesity in both children and adults, developmental disturbance, fertility issues and hormone disruption.
Central Nervous System - excess aspartate (a metabolite of aspartame) produces adverse effects on the structure and the function of the central nervous system and is a substrate for glutamate, which in excess can lead to hyperexcitability of cells, free radical release, oxidative stress and neuronal degeneration.
So, should you be concerned about artificial sweeteners? Possibly. Generally speaking, the only people who we currently know NEED to completely avoid aspartame are those with PUK. And those that should be cautious/worried of artificial sweetener intake are children, pregnant women, nursing mothers, and those prone to seizures, headaches or migraines and those who struggle with IBS.
You might enjoy them and you might find they help you reduce your energy intake which in turn helps you lose weight, but you might also find switching doesn’t have any impact on your weight goals. If you are consuming artificially sweetened products in moderation I don’t really have a great deal of evidence-based ground to stand on and tell you not too, but the reality is that we don’t need them, they don’t offer us anything nutritionally and evidence DOES show us that the sweeter tasting things you consume (regardless of whether it's sweetened with regular or artificially sweetened sugars) the more you increase your preference for sweet foods. This means they don't stop your cravings for sweeter things and ultimately while you might reduce your energy intake from switching soda brands, you’ll probably be more likely to crave and opt for higher-energy less nutritious foods as a whole regardless.
While we now know they are ‘safe’ in the sense that they don’t pose any immediate negative health effects and the previous cancer research has been debunked, the reality is that we still don’t know what the potential long term health effects could be of prolonged intake, specifically their impact on our microbiome.
My personal opinion is that we should all be moving our palettes towards less sweet foods and beverages, regardless of whether they are ‘zero calories’ or not. I also want to pose this… imagine how much less plastic there would be in the world if we all just stopped buying and drinking soft drinks (regardless of what sugar they are made from)? The rate Australians alone go through these beverages… It would be a hell of a lot less plastic in the world! Additionally, I think its also worth mentioning that these artificially sweetened drinks aren’t cheap and one argument we constantly here about healthy eating is that its ‘too expensive’. Ditching the artificially sweetened or regular sweetened beverages could leave you with an extra $20 in your pocket each week which could be spent on fruit and vegetables. (Yes, I am very aware this statement is probably inducing an eye role as I sound like the ultimate party pooper, but it is true…).
So, what's my take-home? The foundation of your diet needs to be full of good stuff. And by good stuff, I mean vegetables, fruits, whole grains, legumes, good quality proteins from animal and plant-based sources, healthy fats and plenty of water. After that, there's a little space left for less nutritious foods consumed in moderation. If you have a sweet tooth and enjoy including some sweeter treats then my advice is stuck to the real stuff. Have small amounts of regular sugar in moderation. If you are on a weight loss journey and can’t give up soda, by all means, try diet drinks, but don’t see it as a way to consume endless amounts of them. Remember while energy intake and energy output is ultimately the basis of weight loss, the foods you choose to get your energy from has a far more beneficial impact on your overall health and well-being.
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