Splenda – or sucralose, has been around since 1976 and on the market for consumption since 1999. It has been marketed as a viable replacement for sugar – but does that mean that Splenda is still safe for consumption? We take a look at some of the current research behind sucralose to determine of it’s safe to put in your body or not.

Is Splenda Safe To Consume?

Before we get started there are a few things you should know about Splenda (also called sucralose):

1. Splenda is made from maltodextrin and glucose – maltodextrin is a synthetic starch produced usually out of corn to enhance sweetness.
2. The recommended daily intake according to the FDA is 5mg/kg.
3. One packet of Splenda contains 12mg of Sucralose.

If you do a search about the safety of Splenda, you’re likely to come across this site: The Truth About Splenda. The site questions the safety of Splenda as a whole and it’s reference point for it’s stance on Splenda refers to a 2008 study questioning the safety of Splenda in regards to gut bacteria. In the study rats were fed Splenda over a twelve week period at 100, 300, 500, and 1000mg/kg. What the study found: over twelve weeks of Splenda intake, Splenda caused a reduction in beneficial fecal bacteria, increased fecal acidity, and enhanced expression levels of P-gp, CYP3A4, and CYP2D1, which limit the bioavailability of orally administered drugs. The changes in the gut were still present for tweleve weeks after Splenda administration stopped (1). Through this, the site, Truth About Splenda was born and some conclusions were made:

1. Splenda is bad for your gut bacteria
2. Sucralocse may cause oral drugs to not be absorbed well
3. Splenda could cause insulin resistance

But hey, rats are rats and people are people, right?

A couple things about this study:

1. It was sponsored by the sugar industry
2. The site, Truth About Splenda was created by the sugar industry

Infact, in 2009, a rebuttal to the 2008 study featured on The Truth About Splenda found that the study was inconsistent with current research available at the time (5). Since then there has been a bit of a back and forth between researchers in the same journal about who was right and who was wrong (1,4,5). The end conclusion: more long term research is needed in humans to determine the safety of Splenda (6).

Moving forward to 2013, a review in the Journal of Toxicology and Environmental health also found that in rats, Splenda was shown to decrease the bioavailability on orally administered drugs – same as the 2008 study featured on The Truth About Splenda. However, what the review also found was that in humans, the effect on sucralose/Splenda has not been able to determine if the sweetener has an effect on orally administered drugs (3).

Findings in rats suggested that Splenda can alter the microbes of the gut – specifically a reduction in beneficial bacteria. Again, research in humans is limited (3).

One big thing from the review is that it showed Splenda/sucralose is somewhat metabolized inside the gut. The findings came after after analyzing stool after ingesting sucralose. Which is important because early research showed that ingestion of Splenda passed through our guts unchanged – a big selling point for Splenda when it first came out. The broken down portions of Splenda are known as metabolites. Unfortunately, the effect of consumption and long term effects of these metabolites on people isn’t known at this time (3).

Another big selling point for Splenda was that it could be used to replace sugar in cooking. However, newer studies have shown that cooking with sucralose at high temperatures starting at 250 about degrees Fahrenheit can generate chloropropanols (a class of potentially toxic compounds) (3,8).

Last of all – and one that actually includes human research (not just rats) – sucralose may alter glucose, insulin, and glucagon like peptide 1 levels. Which means that one of the big selling points – not raising blood sugar levels – may not be all that it is cracked up to be with keeping insulin levels in check (3,9). In obese people –
probably one of the most heavily marketed people of Splenda, it caused a spike in blood sugar and also a spike in insulin secretion. However, the study in obese people showed that there was no increase in insulin sensitivity – unlike several animal studies (9).

The Bottom Line With Using Splenda

Use caution. Research on Splenda has been around since its creation in 1976. It wasn’t until it went on the market in 1999 and up until the mid-2000’s that mass human consumption began to take place. Like most things, long term human research with well designed studies are really needed to determine the effect of sucralose on people. Animal studies have shown that sucralose can cause metabolic effects – but while animals are animals, people are still people. Like other things, the less non-natural substances you can keep from putting into your body, the better off you are.


1. Abdel-Rahman, A., Abou-Donia, M., El-Masry, E., McLendon, R., Schiffman, S. “Splenda Alters Gut Microflora and Increases Intestinal P-Glycoprotein and Cytochrome p-450 In Male Rats.” Journal Of Toxicology and Environmental Health Part A. 2008. Web. 19 March 2015.
2. BROWN, R. J., DE BANATE, M. A. and ROTHER, K. I. “Artificial Sweeteners: A systematic review of metabolic effects in youth.” International Journal of Pediatric Obesity, 5: 305–312. 2010. Web. 19 March 2015.
3. Rother, K., Schiffman, S. “Sucralose, A Synthetic Organochlorine Sweetener: Overview On Biological Issues.” Journal Of Toxicology and Environmental Health Part B, Critical Reviews. 2013. Web. 19 March 2015.
4. Grotz, V., Munro, I. “An Overview Of The Safety Of Sucralose.” Regulatory Toxicology and Pharmacology. 2009. Web. 19 March 2015.
5. Borzelleca, J., Brusick, D., Burks, W., Gallo, M., Killie, J., Wallace-Hayes, A., Williams, G., Xavier Pi-Sunyer, F. “Expert Panel Report On A Study Of Splenda In Male Rats.” Regulatory Toxicology and Pharmacology. 2009. 19 March 2015.
6. Abou-Donia, M., Schiffman, S. “Sucralose Revisited: Rebuttal Of Two Papers About Splenda Safety.” Regulatory Toxicology and Pharmacology. 2014. Web. 19 March 2015.
7. Elinav, E., Israeli, D., Gilad, S., Harmelin, A., Kolodkin-Gal, I., Korem, T., Kuperman, Y., Maza, O., Segal, E., Shapiro, H., Suez, J., Weinberger, A., Zilberman-Schapira, G., Zmora, N. “Artificial Sweeteners Induce Glucose Intolerance By Altering Gut Microbiota.” Nature. 2014. Web. 19 March 2015.
8. Dong, S., Hu, J., Liu, G., Zheng, M. “Polychlorinated Dibenzo-p-Dioxins And Dibenzofurans Formed From Sucralose At High Temperatures.” Scientific reports. 2013. Web. 19 March 2015.
9. Klein, S., Pepino, M., Patterson, B., Tiemann, C., Wice, B. “Sucralose Affects Glycemic and Hormonal Responses To An Oral Glucose Load.” Diabetes Care. 2013. Web. 19 March 2015.