A couple of days ago, I was at my favourite and most trusted Café – Paleo Café and was intrigued by a new brand of health supplements that had hit the shelf that day. I’ve always tried to only buy supplements that are all natural and lower in sugar, yet have struggled with the fact that many of these use sucralose and other artificial sweeteners! Typically, I’d gaze over the ingredients list and be pretty happy with the contents until….that one ingredient tacked on the end that ruins it all and makes me put it right back on the shelf. That is, until I recently stumbled on a couple of brands which refuse to use artificial sweeteners in their products and this got me thinking (and reading as usual)…. so I read, and read and now I want to share with you what I read about implications of artificial sweetener use – particularly sucralose. Read on!

Sucralose to Acesulfame K, to Saccharin and Aspartame, artificial sweeteners are now commonplace in many “sugar-free” foods and supplements, protein powders, drinks, and on coffee shop tables in the form of Equal and Splenda. Yes, Equal and Splenda in particular have both equally been widely scrutinised by health authorities, the media and health promotional sources – and yes – there is continuing confusion regarding the short and long-term health implications of their use. These range from their potential role as carcinogenics, contributors to metabolic syndromes including insulin resistance and diabetes and obesity.

However, what I would like to share, is something extremely interesting that I have recently been made aware of – that is the implications that Sucralose use in particular, has on gut microflora and how this has been scientifically researched and proven to have a profound impact on intestinal health and subsequently, overall health.

So before I go any further, a little background on what Sucralose is – basically, it’s sucrose (table sugar) that has been chemically manipulated to replace three select hydrogen-oxygen groups on the sugar molecule with three chlorine atoms, resulting in an intensely sweet, “zero-calorie” sweetener known as an organochlorine sweetener (OC). Unlike sucrose, sucralose can’t be broken down into calories to provide energy. Yet, similarly to sucrose, sucralose activates the same sweetness receptors (chemosensors) on your tongue and in your alimentary tract that play a role in sweet taste sensation and hormone secretion (Schiffman, S., and Rother, K., 2013). So it is synthetic – completely artificial and has no nutritional value whatsoever – it was designed purely to satisfy sweet cravings without providing calories. Additionally, although tiny amounts are absorbed by the body, (later excreted in the urine) for the most part it travels through the digestive tract and is excreted from the body.

So on the surface, this synthetic compound appears ideal for those wishing to restrict carbohydrate and calorie intake. It is marketed as such – however, what happens to your body as sucralose passes through your body? Well, interestingly and somewhat ironically, it may actually contribute to weight GAIN via several mechanisms!

First and foremost (and probably already widely known), is that the sensation of sweetness stimulates hunger – the body is expecting food that it will need to break down through the secretion of stomach acid and other digestive enzymes and appetite-related hormones. Yet, sucralose provides no digestible calories and as a synthetic molecule that the body does not recognise, it cannot be processed for energy. So, ever wonder why your stomach starts gurgling and you begin salivating after you’ve had a “diet” soft drink or other sucralose (or any other artificially sweetened) containing beverage or food? Well, it is the body’s response to stimulation to digest food, but as there is zero actual calories or nutritive substance being ingested, your appetite regulation is immediately impaired….Commonly, people then feel hungry as a result, even though they are not actually in need of calories for energy. What happens next is naturally reaching for food that will satisfy the hunger cravings – and that often leads to excessive food intake! If this is a recurring pattern – say with a habitual sucralose containing snack or drink once or twice a day in attempt to curb sugar intake, then the purpose defeats itself when excessive food is then eaten as a result of hunger stimulation. It is easy to see how and why so many people fall into this trap and continue to wonder why their hunger is so rampant and they cannot shift weight.

There is another very important and more recent finding regarding sucralose intake and health. This one fascinated me, and I hope will spur you on to read more into this! Sucralose has been proven to affect gut health and decrease gut microflora, having implications for glucose tolerance, gut permeability and glycoproteins. According to Schiffman et al (2008, 2013) and Suez et al (2014), a 12-week administration of splenda exerted numerous adverse effects, including a reduction in beneficial faecal microflora, an increased faecal pH and enhanced expression levels of certain glycoproteins which are known to decrease the bioavailability of orally administered drugs. The researchers also found that these implications persisted even after 12 weeks of cessation of sucralose intake – having implications for longer term health (i.e. sucralose in the short term will potentially affect you in the longer term!)

In another study conducted by immunologist Eran Elinav and computational biologist Eran Segal, both of the Weizmann Institute, a cohort of 381 non-diabetic volunteers who were recruited to answer diet questionnaires; those who regularly consumed artificial sweeteners on average showed higher fasting glucose levels, poorer glucose tolerance, and different gut microbe profiles compared to those who did not consume such sweeteners. The difference between the two populations remained after correcting for body mass index.

These studies are only the beginning of what I am sure will prove to be an extensive research focus in coming years. The increasing knowledge of the important role of gut bacteria in immunity, digestion and metabolism has already prompted some degree of interest in the implications of what we eat on overall health and the link between the two. So, I have only touched on the surface here – for more information, have a look through the references below. The study conducted by Schiffman et al (2013) is comprehensive to say the least!

In the meantime, may I suggest having a look at the ingredients panel of your food, drinks and supplements (even medications as well), to weigh up for yourself whether it’s worth consuming sucralose over sugar. I’m no advocate of sugar, but at least it is a molecule that your body will recognise and digest!


– Schiffman, S. S., & Rother, K. I. (2013). Sucralose, A Synthetic Organochlorine Sweetener: Overview of Biological Issues. Journal of Toxicology and Environmental Health. Part B, Critical Reviews, 16(7), 399–451. doi:10.1080/10937404.2013.842523
– Sugar Substitutes, gut bacteria and glucose intolerance. The Scientist. (2014) http://www.the-scientist.com/?articles.view/articleNo/41033/title/Sugar-Substitutes–Gut-Bacteria–and-Glucose-Intolerance/
– Abou-Donia, M., El-Masry, E., Abdel-Rahman, A., McLendon, R., Schiffman, S. (2008). Splenda alters gut microflora and increases intestinal p-glycoprotein and cytochrome p-450 in male rats. Journal of Toxicology and Environmental Health. 71(21):1415-29. doi: 10.1080/15287390802328630
– Suez et al., (2014) Artificial sweeteners induce glucose intolerance by altering the gut microbiota, Nature, doi:10.1038/nature13793, 2014