Is Splenda safe? After 20 years of government-approved use in the U.S., Canada, and Europe this same question keeps popping up with annoying regularity.
This post provides an overview of the best available scientific evidence regarding Splenda safety.
To be upfront regarding bias, this author has no affiliation with or financial interest in either the sugar industry or the company that promotes and manufactures Splenda.
The Case For Splenda Safety
Splenda – in the powdered form we are most familiar with – is a mixture of a few common forms of carbohydrate “filler” (over 95% of the mix) and a very powerful sweetening agent (sucralose).
In the many years since development and testing began, well over 100 research studies have concluded that there was no evidence for human health risk that could be attributed to Splenda consumption.
As a result of early studies, Splenda was first approved for general use as a sweetener by Canada (1991). With further testing, U.S. Food and Drug Administration (FDA) approval for general use followed in 1999.
The prestigious National Cancer Institute, National Institutes of Health (NIH) has also evaluated the safety of commercially available sucralose-based sweeteners and concluded that there was no scientific basis for associating these products with cancer risks in humans.
As of 2013, the U.S. FDA Acceptable Daily Intake (ADI) for Splenda is 5 milligrams per kilogram of body weight per day (for adults). This translates into about 24 “packets” per day for a 130 lb. person or about 32 packets/day for a 170 lb. person.
The Case For Splenda Concerns
Virtually all of the commonly cited, research-based (which excludes government conspiracy theories) safety concerns for Splenda stem from just three studies:
- Duke University study (2008)
- Ramazzini Institute study (Italy) (2012)
- Washington Univ. study (2103)
We will take a look at the conclusions – and criticisms – of each.
The Duke Study
In a study largely funded by the sugar industry, researchers fed 4 different dosage levels of sucralose to rats for a 12-week period, and then checked a number of health-related variables for change.
The researchers interpreted their findings as evidence for weight gain and a reduction in beneficial gut micro-organisms.
These conclusions were subsequently challenged by a panel of notable experts (convened by the Splenda manufacturers), on the grounds that the study methods were flawed, and so the results of this study could not be properly interpreted as evidence of any harmful effects in the test.
The Italian Job
In 2012, workers at the Ramazzini Institute in Bologna (Italy) reported to the press that research results led them to conclude that sucralose caused leukemia in test animals (mice).
This is clearly the weakest of the three studies, for several reasons:
(1) There has been no independent external review of this research to date. The study at the time of the press release was unpublished – and remains unpublished to this day (August 2013).
(2) The scientific accuracy and validity of prior studies by this laboratory have been found to be highly questionable by governmental health agencies in both the US and Europe.
The highly dubious claims of Soffritti would have gone mostly unnoticed, save for the intervention of a US non-profit “watchdog” – the Center for Science in the Public Interest (CSPI). This group used Soffretti’s unsubstantiated claims to “downgrade” its (CSPI) internal safety status of Splenda, and announced this at their own press release.
The CSPI announcement made for big news – and many misleading headlines – thanks to the efforts of hordes of US health writers ever eager to outdo one another by being the 1st and loudest to parrot any attention-grabbing claim – no matter how unfounded or outrageous that claim might be.
The Washington Univ. Study
The most recent study (published 2013) was done by workers at Washington Univ. (St. Louis) who tested the impact of Splenda on 17 obese human subjects who did not normally use non-nutritive (i.e., “artificial”) sweeteners. The results showed small but significant increases in both insulin secretion and blood glucose levels after sucralose ingestion.
While perhaps of interest to obese people who have until now avoided artificial sweeteners, what do these data tell us about the rest of us? Nothing – “the rest of us” were not addressed by this research.
In terms of our original question, the results of this study provide no evidence whatsoever to support (or refute) the notion that Splenda poses health risks for most healthy Americans.
What are the “takeaways” from this summary review of the Splenda safety issue as of mid-2013?
1. In the 30+ years since development of Splenda began more than 100 applicable research projects designed to test Splenda safety failed to find health risks.
2. Not a single credible study on Splenda safety conducted using human subjects – and applicable to the overwhelming majority of humans – has reported adverse impacts from Splenda consumption.
Bottom Line: There is not sufficient scientific evidence to support the hypothesis that Splenda consumption poses a health risk for healthy adults.