Artificial Sweeteners et al: Aren’t We Sweet Enough?


Sneaky Peek

Evidence suggests that sugar should no longer be our sweetener of choice. What are the alternatives? Are they healthy? The inconvenient truth is that few are “good,” most are bad and some are ugly. Artificial sweeteners are not the get out of jail free card we once hoped they might be, certainly not in terms of the gut microbiome. In fact, it appears that they may do more harm to us than sugar itself. And then there are sugar alcohols and “natural sweeteners” Read on for more detail.

why calorie counting doesn't work

It seems to have become more important to us that food looks and tastes good (for good, read sweet) than that it nourishes us. If I’m going to eat something, I have concluded that it is probably better to eat the real thing – butter instead of margarine, lard instead of hydrogenated fats, sugar instead of aspartame. Here is my thinking on artificial sweeteners, sugar alcohols and natural sweeteners in the context of the gut microbiome.

Until relatively recently, we have been led to believe that there is a simple causal relationship between calorific intake, energy output and obesity. With this simple, causal relationship in mind and with little thought for the “complicating” factor that is the 40 trillion or so microbes that live in our gut, the food industry set out to enable us to reduce calorific intake without giving up sweet foods. They developed artificial sweeteners which are: 1. artificial – they are generally manufactured rather than naturally-occurring. 2. sweet – they are up to 7000 times sweeter than sugar. 3. generally rated as containing no calories – they are so sweet that only a very small amount is required per serving, meaning that a typical serving delivers no calories. Sugar contains 4 calories per gram. I guess the idea was that we could have our “cake” and eat it because it didn’t contain sugar.

We now understand that our gut microbiome is a crucial interface modulating our metabolic response to food (1), meaning that this process is not a straightforward energy in - energy out equation. This partly explains why one person can eat what they want and not put on weight, whilst someone else will eat carefully and struggle to manage their weight. It also means that our gut microbes, their composition, diversity and abundance can be influenced by what we consume.

Nearly all soft drinks on supermarket shelves contain artificial sweeteners as do medicines, toothpastes, children’s vitamin supplements, low fat yogurts, processed foods, salad dressings. They are ubiquitous. And they are not designed to encourage us to move away from sweet foods towards genuinely nourishing foods. They are designed to keep us hooked on sweet things without consuming sugar, itself.


Here are the names of just some of the most commonly used artificial sweeteners. Confusingly, they often go by varying brand names so that can make it harder for us to spot them in the foods we buy:

Saccharin (E954, brand name e.g. Sweet’N Low, Necta Sweet, Heremesetas),

Sucralose (E955, brand name e.g Splenda),

Aspartame (E951, brand names e.g. Nutrasweet, Canderel),

Aspartame-acesulfame Salt (E962, brand name e.g Twinsweet),

Acesulfame Potassium (E950, brand names Sweet One Sweet & Safe), Cyclamate (E952, brand names Sucaryl, Cologram).


what artificial sweeteners do

B.E.G.M.U.(Before the Era of Gut Microbiome Understanding), it was believed that most artificial sweeteners were excreted unchanged from the body and, as a result, were metabolically inert and had no physical impact on us. Now, it appears that our gut microbiome, the crucial factor in modulating our metabolic response to food, is the interface through which artificial sweeteners impact us. We know that the composition, abundance and diversity of our gut microbiome can be altered depending upon what we eat and we also know that our gut microbiome can impact our metabolic response to food (2, 3, 4). Research on artificial sweeteners shows that they may significantly affect the abundance and diversity of the bacteria in our guts (particularly bifidobacteria) (5) and therefore the bacterial by-products produced. The bacterial by-products of artificial sweetener metabolism may then act as messengers influencing metabolic pathways in our body.

In 2015, an Israeli research team carried out an experiment on mice (6) to see the impact of artificial sweeteners on our gut microbiome. One group of mice were given water that contained natural sugars (glucose or sucrose (sucrose is made of glucose and fructose), the other received water that contained an artificial sweetener. Both groups ate a diet of normal mouse food.

The researchers were surprised to discover that animals in the artificial sweetener group developed a condition called glucose intolerance. This is characterized by high blood glucose levels and is an early warning sign of Type 2 diabetes. In contrast, the mice that drank the sugar water remained healthy.

The results were puzzling. The researchers wondered if the answer might be explained via changes in the gut microbiome. When they investigated this, they found a distinctly different collection of microbes in the mice who drank the sugar water compared to those who drank the artificially sweetened water. The bacteria that colonized the mice drinking the artificially sweetened water were the same types of bacteria that have been shown to be particularly abundant in the guts of obese mice.

When the researchers used antibiotics to wipe out the gut bacteria in the mice drinking the artificially sweetened water, their blood glucose levels returned to normal—evidence that the gut microbes were actively involved in the glucose intolerance.

They then carried out this experiment on humans and the results also showed that long term users of artificial sweeteners tended to have higher levels of blood glucose and an altered gut microbiome.

Other studies suggest that, by causing increases in pH and disruption to our gut microbiome, artificial sweeteners can cause gut barrier dysfunction and damage (5, 7). It seems likely that artificial sweeteners arrive largely undigested in our colon, where they have a detrimental effect on our microbes which results in alterations in metabolic function.

Ironically, artificial sweeteners have also been shown to cause an increase in consumption of sweet foods. They fail to provide the satiety signals genuinely sweet food can and thereby fuel a desire for increasing amounts of sweet food. In addition, our bodies detect that they contain no calories and therefore seek to fill that satiety gap with other foods.

How we respond to artificial sweeteners could be down to our particular gut microbial profile in the first place but the concern is that, in some of us, they may have a detrimental effect on our gut microbial population resulting in metabolic issues and gut lining dysfunction.


artificial sweeteners are a problem not a solution

Whilst writing this, I have had these recurring thoughts 1. Why? 2. How? Why do we avoid confronting what is staring us in the face and how can we be so stupid? Even if we knew nothing of the truly mind-blowing bacterial ecosystem living in our guts, I think most of us realise that processed sweet foods are a problem. They do not nourish us. In what parallel universe is the solution to our issues with sugar ever going to involve making artificial chemicals which contain no calories and are thousands of times sweeter than anything that occurs in nature so that we can keep eating really sweet things?


And it is not just artificial sweeteners. What about sugar alcohols and “natural” sweeteners?  We are hunting for “healthy” ways to keep eating and eating more and more sweet-tasting things that historically, were very limited in availability for us – we could only generally get them in Autumn and they contained fibre and phytochemicals – fruit!

The idea of having our cake and eating it is a fallacy. It seems obvious now that our body would be too intelligent to be fooled by artificial sweeteners and doubly so now that we know of the existence of this entire Lilliputian world within our colon. It also seems somewhat foolish to cling desperately to the need to keep using sweetness to fire our dopamine sensors in the face of all the evidence of the negative consequences to health of doing so. The next evolutionary step needs to be away from being slaves to instant pleasure through sweet food and drink, regardless of the source of the sweetness.


other non-sugar non-solutions

Originally, there was a second part to this piece, which was about sugar alcohols and “natural” sweeteners but having wasted a small part of my life researching it, I have decided not to waste yours telling you about it. Here is the synopsis:

Sugar alcohols are made of a hybrid between a sugar molecule and an alcohol one. They are not calorie free but have fewer calories than sugar and are used in many “sugar free” and diet products. We can’t digest them but some of our microbes can. Whilst they also exist in fruit and vegetables, the issue is our ability to consume large volumes of them in processed food/drinks. They arrive in the colon largely unprocessed and can cause severe digestive distress – excessive wind, bloating and diarrhoea as the microbes in our colon ferment away wildly. In addition, the alcohol element of sugar alcohols can cause passive diffusion to draw water into the colon. Undigested substances in the colon can then begin to rot, creating the perfect environment for undesirable bacteria to thrive thereby disrupting our gut microbial community.

Even the ones that sound “natural” are heavily refined. Examples are Xylitol, Sorbitol, Erythritol, Isomalt, Lactitol, Maltitol and Mannitol.

As for natural sweeteners, I have researched a long list of them (honey, stevia, maple syrup, molasses, agave, yacon syrup, date syrup, coconut sugar, you name it….) and how we can manipulate them to be able to carry on making cakes and biscuits without using sugar itself. Admittedly, some do contain minerals and vitamins. Some even contain inulin, a prebiotic fibre that feeds our microbes. But let’s not follow the rest of humanity down that justificatory rabbit hole. It is not common sense but good marketing (and being dopamine addicts) that allows us to think that these products may be healthy in the round.

In a nutshell, I have learnt that most of these “natural” sweeteners are so highly processed that any genuinely beneficial element is eradicated and we are left consuming a simple sugar dressed up in a different outfit. If I want something sweet, my best bets are raw honey (pasteurising kills all the beneficial enzymes, antioxidants and bacteria it contains), genuine dark maple syrup (as opposed to the fraudster maple syrups which are, in fact, some highly refined syrup that is maple syrup FLAVOUR) or raw Stevia (the processed Truvia has gone through something like 42 processing steps including adding chemical solvents to make it as sweet as possible).


no short cuts

The more I read about the health issues facing humans, the clearer it becomes to me that we can’t keep giving in to our dopamine sensors when it comes to sweet food. (Read my piece on The Pleasure Trap.) The evolutionary job dopamine performed to ensure survival by motivating us to seek out calorie-dense foods when we were cave men has become the complete opposite –  a way of increasing the levels of non-communicable diseases exponentially (Type 2 diabetes, cardiovascular disease and the like). By 2020, the WHO believes that non-communicable diseases will be the biggest issue affecting health. Those of us (the majority, it would appear) that struggle to resist the call of sweet foods – whether they contain sugar, artificial sweeteners, sugar alcohols or “natural” sweeteners – are making ourselves ill. The next step in our evolution is to be able to ignore our dopamine sensors in terms of sweet food until we have retrained them to reward us for consuming nutrient dense whole foods.

Which means that artificial sweeteners, sugar alcohols and “natural” sweeteners are just alternative routes that lead to a similar place sugar takes us. That increasingly well-known destination of ill health.

My response here has involved a change in shopping habits. Firstly, this is my small way of protesting at food manufacturers exploiting our evolutionary wiring. Secondly, the desire for sweet things is currently hard wired and hard to resist. So avoiding having temptation in the house really helps.

And when we do make a cake, we use sugar. We are acknowledging that we are having a rare treat. But I am not making many cakes any more. My resolve muscle is strengthening each time I exercise it. There are more loving ways of showing love. There are certainly healthier ways of showing love.


Read food labels (even the ones on foods we believe to be healthy) and look out for sugar, artificial sweeteners, sugar alcohols and “natural” sweeteners.

Buy fewer foods with food labels.

Buy more foods with NO labels – whole foods.

Try to notice when our dopamine strings are directing our food choices. And then start the evolutionary process by crossing these items from the shopping list. This will help us at a gut microbial level and on every level. Vive l’Evolution!


  1. Bacteria from lean cage-mates help mice stay slim Nature – Jeffery Gordon of Washington University’s research on putting lean and obese microbes into mice September 2013
  2. Mechanisms in endocrinology: Gut microbiota in patients with type 2 diabetes mellitus. Allin KH, Nielsen T, Pedersen O. 2015 European Journal of Endocrinology (T2 diabetics tend to have perturbed gut microbiota)
  3. Bacteria from lean cage-mates help mice stay slim Nature – Jeffery Gordon of Washington University’s research on putting lean and obese microbes into mice September 2013
  4. Linking long term dietary patterns with gut microbial enterotypes: Wu, G.D. Science 7 Oct 2011334 (6052) 105-8
  5. Splenda alters gut microflora and increases intestinal p-glycoprotien and cytochrome: Abou-Donia M.B J Toxicol Environ Healthy A (2008) 71 (21): 1415-29
  6. Non-caloric artificial sweetners and the microbiome: findings and challenges: Suez J, Korem T, Zibeman-Schapira G, Segal E, Elinav E Department of Immunology ; Weizmann Institute of Science; Rehovot,, Israel. 2015;6(2) 149-55 NCBI
  7. Canadian Journal of Gastroenterology Sep 2011, (25) 9:511-511


Spreading straightforward information about the fundamental importance of a healthy gut microbiome.