A study published in the scientific journal Nature shows that artificial sweeteners such as aspartame, saccharin & sucralose may damage the microbes living in your gut to create an environment conducive to poor glucose metabolism, obesity, inflammation & disease.

In the experiment performed in Israel, researchers took 10 week old mice & fed them a daily dose of aspartame, sucralose or saccharin. A control group were given the natural sweeteners glucose or sucrose. After 11 weeks, the mice receiving the natural sweeteners showed normal, healthy physiology, whilst the mice receiving daily doses of artificial sweeteners showed abnormally high blood glucose levels which is a precursor for a range of health ailments from diabetes, obesity & heightened risks of liver & heart disease.

Your gut bacteria have been shown to have a large influence on your blood sugar response due to their ability to regulate inflammation & maintain insulin sensitivity within the cells. Eran Segal, biologist & one of the study’s leaders, said that whilst on artificial sweeteners the mice’s microbiomes (their gut bugs) became similar to those shown in other studies to be associated with obesity.

Its been shown that genetically obese mice have around 50% fewer Bacteroidetes (a subgroup bacterial species), & 50% more Firmicutes (another subgroup) than their lean counterparts. This is important because researchers have been able to transfer microbes across mice groups to manipulate weight control. Firmicutes bacteria for example, have been shown to increase weight gain by producing more ‘energy-harvesting’ enzymes within the gut so that more energy is extrapolated from food, & they switch on ‘fat-storing’ genes within the host. Artificial sweeteners it seems may contribute to an environment similar to this ‘obese’ microbiome. An important note is that after being treated with antibiotics & having their gut microbes return to ‘normal’, the elevated blood glucose stabilised (still, antibiotic treatment may not always be the best course).

The Israeli team also analysed a database of 381 men & women & found that the consumption of artificial sweeteners was positively associated with being overweight & poor glucose metabolism.

So it could be, the evidence seems strong enough, possible to say that artificial sweeteners, rather than helping us lose weight are actually shifting our bodies into a state where we actually become more overweight. 

This throws into perspective the very idea of sweeteners in the first place. We have access to a wide range of naturally sweet foods such as apples, berries, beetroots & sweet potatoes yet the desire for that little extra sweetness still remains. If we’re interested in attaining good health & longevity then it would be in our best interest to actually re-sensitise our taste buds for sweetness! Once you’ve been on a low-sugar, in-season, clean, organic diet for a while (like the approach I outline in The Gut Healing Protocol) you’ll find that the sweetness in onions, carrots & beetroots is quite satisfying in itself.

Natural alternatives to artificial sweeteners, like stevia, may be a good option, however if we are interested in losing, or rather re-sensitising, our tastebuds to sweet, then just plain, whole food is always the best answer.

Want to learn how you can rebalance your microbiome in 8 weeks? 

Resources for this article:

Suez J, S. (2016). Artificial sweeteners induce glucose intolerance by altering the gut microbiota. – PubMed – NCBI. [online] Available at:

Mutzel, Mike. Belly Fat Effect. Print.

Shell, Ellen Ruppel. “Artificial Sweeteners Get A Gut Check”. Sci Am 312.4 (2015): 32-34. Web.