How Artificial Sweeteners Alter Your Gut Bacteria and Harm Your Health


Artificial sweeteners are one of the most widely used food additives today – found in everything from soft drinks to cakes and yoghurt. They have long been promoted and endorsed as a safe alternative to sugar due to their low caloric intake – however studies have not found any impact on weight loss or obesity. Now strong evidence has highlighted the damage they do to our gut microbiome with severe implications for our health.

What are artificial sweeteners

Artificial sweeteners or Non-Caloric Artificial Sweeteners (NAS) as they are often known – are a sugar substitute added to food and drinks to provide a sugary taste without or with significantly fewer calories, or food energy. There are some natural sugar substitutes such as stevia, but most are synthetic or artificial. There are six artificial sweeteners deemed Generally Recognized as Safe (GRAS) by the FDA. The most commonly used non-caloric artificial sweeteners are saccharin (Sweet’n Low), aspartame (Equal, NutraSweet and Canderel), and sucralose (Splenda)

Where are they used

As sugar has been identified with mounting health and obesity problems – resulting in opposition from consumers and healthcare providers, the food industry has been turning to artificial sweeteners instead and is expected to reach $2 billion in 2018.

They are found in a variety of foods including soft drinks, chewing gum, jellies, baked goods, candy, fruit juice, and ice cream and yogurt. They are usually identifiable as these products are marketed as “low sugar”, “sugar-free” or “diet”?

Aren’t artificial sweeteners safe?

They have been scrutinised intensely in the past and were identified as a cause of a number of health problems including cancer following studies of the effects of saccharin in laboratory rats. Yet studies found the sweeteners not to be carcinogenic so they continued to be recognized as safe by the US Food and Drug Administration.

So what has changed now?

In a recent report, published in the Canadian Medical Association Journal, researchers analyzed 37 studies into artificial sweeteners to see their effects on weight management and health. The studies – which tracked over 400,000 people for about 10 years, including 7 randomized controlled trials, suggested that people who regularly drank soft drinks or foods containing artificial-sweeteners had a higher risk of weight gain and obesity as well as diabetes and heart disease.

Meanwhile in a widely publicised study conducted at the Weizmann Institute of Science, Israel researchers examined the effect of artificial sweeteners on our gut microbiome – and found that rodents fed with artificial sweeteners saw significant changes to their gut microbiota – with a reduction of beneficial strains of bacteria and increased quantity of harmful bacteria strains associated with obesity, metabolic disease and diabetes,

In this study the researchers added saccharin, sucralose, or aspartame to the drinking water of three different groups of lean 10-week-old mice along with several control groups that included mice drinking only water or mice drinking water supplemented with glucose or sucrose, to see how the artificial sweeteners compared to normal sugars.


Warning - Sacharin may damage your health

Artificial sweeteners such as Sacharin may alter your microbiota and damage your health

How do they effect the microbiota?

When they examined the faeces of the mice they found that 40 different strains of bacteria they were monitoring had significantly altered in abundance in the mice consuming the artificial sweeteners, an indication of considerable dysbiosis.
This alteration resulted in inflammation in the liver and glucose intolerance – any early from of diabetes.

How do they effect humans?

Several studies into the consumption of artificial sweeteners in humans have found them to be associated with glucose intolerance. In a study published in nature, seven healthy volunteers who do not normally consume artificial sweeteners were fed the FDA’s maximal acceptable daily intake of saccharin (5 mg/kg body weight) as three daily doses. They were monitored by continuous glucose measurements and daily glucose tolerance tests.


Astoundingly, in just this short week-long period, four out of seven individuals had already developed significantly poorer glycemic responses and were found to have significant changes in the makeup of their microbiota. The remaining three individuals had no change (NAS non-responders).

What does this mean:

There are a number of studies we referenced here in passing – and if you consume a lot of artificial sweeteners and are concerned about the effects we recommend you look into these findings in more depth. Our key points for you to consider are:

  1. People who consumer artificial sweeteners regularly have higher risk of weight gain, obesity, diabetes and heart disease. 
  2. The consumption of artificial sweeteners in both mice and humans alters the gut microbiota and increases the risk of developing glucose intolerance and metabolic diseases. 
  3. As the use of artificial sweeteners continues to rise – we need to examine all food labelling and reduce or remove processed foods from our diets if we want to avoid them.

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