Sucralose is Not “Safe”: A Scientific Review

I recently posted an article entitled “Aspartame Is Not “Safe”: A Scientific Review,” which explained why aspartame, aka aspartylphenylalanine, is not safe. So, I will also review scientific studies which illustrate who sucralose not safe either.

The definition of safe I am using is Merriam-Webster’s definition of safe, which is “free from harm or risk.”

In this article, we will examine scientific studies which investigate the safety of sucralose.

May Increase the Chance of Diabetes and Obesity

Ironically, even though sucralose marketed as a no-calorie sweetener, studies have claimed sucralose be linked to weight gain and an increased risk of diabetes.

A 2009 study investigated the relationship between diet soda consumption and one’s risk of type 2 diabetes. The researchers found that even though the soda was diet and had no sugar, daily use of diet soda resulted in a 67% greater relative risk of type 2 diabetes [1]. This could mean sucralose is an unexpected diabetes trigger, so if you were wondering is sucralose was good for diabetes, the clear answer is “no” because it can actually increase your risk.

In 2013, researchers evaluated this paradox. The researchers had 17 obese individuals who were insulin-sensitive take an oral glucose tolerance test after consuming either water or sucralose. The researchers found that after drinking the glucose, the participants experienced an increase in insulin and a higher insulin secretion rate [2]. The researchers also profoundly noted there was an “increase in peak plasma glucose concentrations” and a 23% decrease in insulin sensitivity in the study [2]. This information means sucralose if not safe for patients with diabetes.

An additional study linked sucralose to diabetes-associated metabolic changes [3].

Shown to Be Harmful to the GI Tract

Sucralose seems to be harmful to the GI tract in two ways: damaging the microbiome and increasing the risk of leaky gut.

A 2016 study found sucralose to disrupt the balance and diversity of gut microbiota [4].

A 2013 study found sucralose to reduce the overall number of bacteria in the gut, sucralose disproportionately lowered levels of beneficial bacteria including lactobacilli and bifidobacterial, and sucralose increased the proportion of harmful bacteria called enterobacteria [5]. This reduction was not even able to be reversed three months after forgone sucralose use [5]. Another study also confirmed these changes [7].

A new, 2019 study also had some interesting findings. The researchers found, “The consumption of sucralose decreased the total number of anaerobic and aerobic bacteria, bifidobacteria, lactobacilli, Bacteroides, and Clostridium” [6]. Sucralose also leads to higher inflammation levels by changing levels of other intestinal microbiotas [6].

In 2009, Xin Qin, M.D., Ph.D., from New Jersey Medical School found the consumption of sucralose can cause IBS, ulcerative colitis, and Crohn’s disease [8]. Qin made this discovery when he was researching the rapid increase of IBS cases in Alberta, Canada. Within 20 years, IBS cases increased by 643%. After his extensive research, Qin claimed it was most likely due to sucralose’s effect on gut bacteria [8] [14].

A 2018 study confirms Qin’s thoughts. The study found the use of artificial sweeteners, including sweeteners containing sucralose, doubles one’s risk of Crohn’s disease and can impair bacteria activity in the guts of people who have Crohn’s or other pro-inflammatory conditions [9].

Studies have also linked sucralose to leaky gut disease because it kills probiotics and can harm the intestinal wall, as noted in one study [10]. For example, in 2008 the Journal of Toxicology and Environmental Health published a study out of Duke University Medical Center illustrating sucralose sweeteners not only significantly reduces beneficial bacteria but also made the gut more acidic, which can result in decreased nutrient absorption [11].

To summarize, sucralose can harm the GI tract by destroying the microbiome balance, increasing the chance of Crohn’s or other inflammatory diseases, and making the gut more acidic.

Associated with Weight Gain

Sucralose consumption has also been linked to increased weight gain.

In a 2012 study entitled “A trial of sugar-free or sugar-sweetened beverages and body weight in children,” researchers investigated the weight-gaining effects of replacing noncaloric, sugar-free beverages with sugar-containing beverages. (Yes, I typed that correctly.) The researchers found drinking sugar-sweetened beverages resulted in reduced weight gain when compared to drinking sugar-free drinks [12]. Also, in a 2013 study, researchers found there is no consistent reduction of weight gain through consuming sucralose-sweetened beverages when compared to sugar-sweetened beverages [13].

It is Toxic and Carcinogenic

This may seem straightforward, but it is hard to describe the toxic and carcinogenic effects of sucralose fully.

A 2016 study published in the European Journal of Nutrition concluded that rats metabolize sucralose in the same way they metabolize other harmful drugs and toxins. The body treats sucralose as a poison and works fast to remove it [15].

Scientists also found a wide range of other issues caused by sucralose. In an older, 1990 study, scientists found long-term exposure to sucralose can lead to bowel enlargement, kidney mineralization, and changed to pelvic tissue [16].

Through the manufacture of sucralose claims the substance passes through the body without causing any change; this is untrue because 11-27% if absorbed by the body [17].

Perhaps the most ironic fact about sucralose is that it is marketed as “ideal for cooking,” but that is entirely untrue.

When sucralose is heated to 248℉, sucralose degrades into toxic compounds like chloropropanol and deadly dioxins [18]. This completely negates the claim that sucralose is “ideal for cooking.”


To summarize, much like aspartame, sucralose is not safe. Many studies have linked sucralose consumption to diabetes, obesity and weight gain, Crohn’s disease, and other toxic effects.

If you would like to view more studies illustrating why sucralose is not safe, see reference [19].

If you are interested in any natural sweeteners which do not have these adverse effects, please feel free to call out office at 800.726.1834.