Artificial Sweeteners Disrupt Blood Sugar Control By Altering Gut Bacteria

| October 9, 2014

Artificial sweeteners have long been promoted as aids to weight loss and for helping people with diabetes to control their blood sugar levels. The official advice from Diabetes UK is that “Low-calorie sweeteners are sugar substitutes that have zero calories and do not raise blood glucose levels through eating them, which makes them a preferable choice for diabetic people over sugar”.

That advice sounds good in theory – but unfortunately it totally falls apart in the light of recent scientific research! It has become clear that artificial sweeteners don’t help weight loss and, contrary to conventional thinking, they do raise blood sugar levels even though they contain no sugar or calories. In fact, as I reported earlier here, sugar-free beverages and other products containing artificial sweeteners may actually cause the very problems they are meant to avoid.

New research has shown that artificial sweeteners have a previously unsuspected effect; they change the composition and function of the gut bacteria in a way that leads to glucose intolerance, the first step on the path to metabolic syndrome and type 2 diabetes.1 And these changes can happen fast – in as little as one week of consuming artificially-sweetened products! These findings, published recently in the scientific journal Nature, are proof that the widespread use of artificial sweeteners in food and drink products is contributing to the worldwide epidemics of obesity and diabetes.

In this study, scientists gave mice water laced with artificial sweeteners (saccharin, sucralose and aspartame) in amounts equivalent to those permitted in human foods. They found that the mice developed glucose intolerance, when compared to mice given plain water or even sugar water. Glucose intolerance is a pre-diabetic state of raised blood sugar that is associated with insulin resistance and an increased risk of heart disease. By using antibiotics to eradicate gut bacteria and by transplanting bacteria from mice exposed to sweeteners into other mice, the researchers established beyond doubt that changes in the gut bacteria were responsible for the development of glucose intolerance.

To see whether humans would react to artificial sweeteners in the same way as the laboratory mice, the researchers asked volunteers who did not generally eat or drink artificially sweetened foods to consume them for seven days. Test results showed that most of the volunteers were starting to develop glucose intolerance after just one week of artificial sweetener consumption, although others were not. This difference in susceptibility was explained by the composition of their gut bacteria – the researchers discovered that the volunteers carried two different bacterial populations, one that induced glucose intolerance when exposed to the sweeteners, and one that did not.

The study authors believe that certain kinds of gut bacteria react to artificial sweeteners by secreting substances that provoke an inflammatory response similar to that caused by sugar overdose, promoting changes in the body’s ability to utilise glucose. This research helps to explain the earlier finding, which I reported here, that women who drank ‘diet’ sodas were more likely to develop diabetes than those drinking the regular, sugar-sweetened versions.

Artificial and natural (and not-so-natural) sweeteners

The new research shows that saccharin, aspartame and sucralose all cause glucose intolerance (and other artificial sweeteners probably do the same). Here is a quick rundown of sugar substitutes and some of their other health effects:

Saccharin – early animal studies found it was associated with higher cancer risks.

Aspartame – evidence that it may be linked with many health problems including depression, multiple sclerosis, dementia, epilepsy and Parkinson’s disease.

Sucralose – could cause bloating, nausea, diarrhoea, headaches and anxiety.

Advantame – this new relative of aspartame is likely to be just as big a health disaster, as I reported here.

Maltitol, sorbitol, xylitol etc are ‘sugar alcohols’. They do contain calories and may raise blood glucose, but much less than sugar does. Overconsumption could lead to digestive problems. Xylitol is the best of this bunch and has been found to reduce insulin resistance in animal studies.

Agave nectar – although natural in origin, the highly-refined products that are widely available contain around 75 per cent fructose and could cause the same health problems as high-fructose corn syrup here.

Stevia/Truvia – natural stevia leaf is a really great option, but most popular ‘stevia’ products, including Truvia, are produced in a laboratory from stevia lookalike chemicals and artificial sweeteners and contain no real stevia.

The myth that artificial sweeteners can help people with diabetes to control their blood sugar and lose weight is now well and truly dead. And another one to bite the dust recently is the idea that low-fat dairy products can help prevent type 2 diabetes. New research shows, to the contrary, that full-fat dairy products are the real stars in diabetes prevention. I shall tell you all about this in my next blog post.

Wishing you the best of health,

Martin Hum
PhD DHD Nutritionist
for Real Diabetes Truth

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1. Suez J, Korem T, Zeevi D et al. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature, 2014 Sep 17 (Online ahead of print).

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Comments (2)

Testimonials are based on the personal experience of individuals. Results are not typical and the potential benefits of taking any drug or supplement may vary depending on your individual needs and health requirements. Please consult your GP before making any changes to your medical regimen.

  1. Roland says:

    As Type II diabetic, I have used Xylitol and had no adverse reaction but it is comparatively expensive and uses are limited.
    For the past month or so I have been using a stevia extract in my coffee and again, had no adverse reaction. I haven’t found stevia leaf on sale. It seems that the leaf itself, being 200 times sweeter than regular sugar has to be processed to make an extract that is useable.
    Because of the way they trick the brain, it is no surprise that the chemical sweeteners mentioned have been found to be harmful. Similarly, the all pervasive corn derived glucose-fructose in processed foods must be avoided at all costs.

  2. James Kellock says:

    These findings about artificial sweeteners are no surprise to me. I was on them for about 15 years as an alternative to sugar before I was diagnosed as being Diabetic.

    I firmly believe they were the cause of me becoming Diabetic.

    If this research is proven, how would one stand on the subject of compensation from the sweetener manufacturers?

    Many thanks for highlighting this.