Why You Should Never Use Splenda (Sucralose)

I’m often asked which artificial sweeteners and sugar substitutes I prefer. The answer, quite simply, is few of them because most create a wide variety of negative side effects. The newest, Splenda (Sucralose), has its own dangerous history and set of dangerous consequences. The dangers of Sucralose and the side effects of Sucralose cannot be denied. Sucralose is marketed and commonly known as Splenda. I use both names in this post.

Let’s look at some surprising facts about Sucralose:

Sucralose History and Testing

Sucralose was discovered by a grad student in London in 1976 while working on a study focused on creating new INSECTICIDES. That’s right. Splenda was “accidentally” discovered as part of a research study focused on creating death agent insecticides. (On a side note, DDT, a poison now banned, has a very similar chemical structure to Sucralose. Doesn’t that sound delicious?) McNeil Nutritionals, the manufacturer of Splenda, claims that hundreds of studies were done on Splenda. The truth is that most of those studies were designed and paid for by McNeil (which puts their validity in question) and that almost all the studies were performed on animals, were very short term, and did not test safety but instead tested secondary effects such as tooth decay. This means that McNeil never tested the effects Splenda has on the endocrine system, metabolism, liver and kidney function, or any other physiological effects.

The truth is that only six human studies were conducted, the longest of which was three months. (Most people use Splenda far longer.) For more information on the ways research studies and their results are often faulty, please read my post Simple Ways to Evaluate the Validity of a Research Study. NO studies on Sucralose safety have been conducted on children or pregnant women, in spite of the fact that studies performed on rats showed the offspring of pregnant females fed Splenda had decreased intelligence, smaller sexual organs, failed to thrive and had a variety of behavioral problems. Splenda is also commonly used in products strongly marketed to children, even though the manufacturer doesn’t know for sure that it’s safe for children to consume it. Independent human studies showed Splenda impaired liver function, caused enlarged kidneys and liver, decreased the number of red blood cells in the blood (caused anemia), impaired absorption of essential minerals such as magnesium and potassium, and caused significant shrinkage of the Thymus gland, one of the most important glands involved in immunity.

Splenda side effects have also been strongly linked to psychological problems including dementia, severe depression and sleep disorders. Splenda has also been linked to increased rates of autoimmune disorders such as Multiple Sclerosis, Lupus, Diabetes and others. The most common side effect of Splenda is digestive disturbances such as gas, bloating, diarrhea, nausea and vomiting. Increased cataract rates were also noted.

The biggest insult is that use of Splenda has been linked to–you guessed it–weight gain. An independent study performed at Duke University and published in the Journal of Toxicology and Environmental Health confirmed that use of Splenda causes side effects such as weight gain and multiple digestive disorders, some with symptoms as severe as Crohn’s Disease. If you haven’t thrown away your box of Splenda yet, please read on.

Chemical Structure of Sucralose:

Proponents of Sucralose claim it is “natural” because it’s made from sugar. The truth is that chemists took the natural sugar molecule and combined it with chlorine. Chlorine is a known poison which is very commonly used in insecticides and in current and past biological warfare agents. (Remember the Chlorine Gas used in WWII? More recent biological warfare agents still use chlorine but are even more deadly.) McNeil claims chlorine occurs in nature and in our foods, another untruth. The truth is that chlorine only occurs in chemistry labs. Chloride occurs in nature, but only when combined with other chemicals that make it a non-poison. One of the reasons Splenda has no immediate effect on blood sugar is because your body does not recognize it and it cannot be absorbed by the digestive tract.

The problem, which McNeil admits, is that your body absorbs 15-18% of the Splenda consumed, but has no means to eliminate it. Your body cannot eliminate it because it is a chemical structure your body was not designed to eliminate. When you consume Splenda, your body is absorbing chlorine and other toxins from Splenda, but the chlorine–a known poison–has an almost indefinite afterlife in your tissues. Tissues and cells which have absorbed a toxic substance do not function correctly. Period. (Watch for a future post on the damaging effects chlorine in tap water has.)

If those terms were overly simplified, here’s the chemical explanation: To create Splenda, the organic sugar molecule is treated with acetic anhydride, trityl chloride, hydrogen chloride, thionyl chloride and methanol. This all occurs in combination with toluene, dimethylformamide, 4-methylmorpholine, methyl isobutyl ketone, acetic acid, benzyltriammonium chloride, and sodium methoxide. The end result is not a sugar molecule, but is a chlorinated hydrocarbon molecule.

The most common uses of chlorinated hydrocarbons include insecticides, chemical solvents and degreasers, and the production of plastics. Many chlorinated hydrocarbons are being banned from industrial use because of their environmental toxicity and because their use accelerates the destruction of the ozone layer. Does that sound like something you want to consume on a daily basis?

Needless to say, Splenda is a banned substance in my home. The side effects and dangers of Splenda are too dangerous to allow. A fairly complete list of commercial products containing Sucralose can be found at Sucralose US Product List. The list is shockingly huge and contains many products aimed at children. This concerns me greatly.

Sugar Substitute Alternatives

My choice of a non-caloric sweetener and sugar substitute that has no glycemic effect is Stevia. Stevia is an herb which is 300 times sweeter than sugar but which has NO known side effects. (Some recent studies suggested Stevia may decrease testosterone levels in men, but those studies used faulty protocols that guaranteed negative side effects.) Stevia is the only sweetener (other than coconut sugar and agave nectar) we use in our house. My favorite Stevia is made by the company SweetLeaf. I carry it with me everywhere. You can purchase it in most groceries or on Amazon (SweetLeaf Packets or SweetLeaf Liquid).

If you want additional information on the dangers of artificial sweeteners, I highly recommend Dr. Mercola’s book, Sweet Deception.

Just out of curiosity, what sweetener do you use? Have you had negative effects from an artificial sweetener? If so, please share! Help others avoid the danger!


By IndyHealer

Pamela Reilly is a Naturopathic Nutritionist with a burning passion for helping others achieve wellness using an integrative approach combining mainstream medicine with natural modalities. She has over 20 years of experience in natural medicine, has multiple certifications, and is currently completing a doctorate in Naturopathic Medicine. She is part of the practice of The Logan Institute for Health & Wellness in Fishers, Indiana. She is available for consultations in person or over the phone and can be reached at 317.598.4325.

17 replies on “Why You Should Never Use Splenda (Sucralose)”

I realise this is an old post, but I saw it late and I am somewhat of a health nerd, so…

In response to your question in the article: I avoid all artificial sweeteners. If I need sweetness, I use good ol’ sugar. Plain and simple. I am a bit suprised that no one in the comments has suggested it yet?

Of course, my aversion stems from the fact that any and all artificial sweetener tastes like bile to me. Basically I avoid it like the plague because I abhor the flavour so much.  Then again, I don’t actually drink sweetened beverages. Since I don’t use sugar in coffee or tea, and I don’t like soda, there is little left to spoil with artificial sweetener.

As has been rightly mentioned, not even diabetics really need the artificial sugar replacements. The key is to control the intake of simple (and complex) carbohydrates in order to maintain a steady level of blood sugar, not to eliminate all cabs (sugars). After all, low levels of blood sugar can be very dangerous to a diabetic as well…

I agree that diabetics a) can have small amounts of sugar, as the diabetic diet depends more on glycemic index than anything and b) low blood sugar is as bad (actually some studies have indicated worse) as high blood sugar. I do not think, however, that giving up artificial sweeteners is wholly realistic for every diabetic, and and that they can be important tools, especially for people in the transitional process of switching to the diabetic diet.  I disagree strongly,however, with the scare tactics and fear mongering which surrounds artificial sweeteners.

Thanks so much for all your comments! I do appreciate them! I am sorry some of you felt my post was unfeeling toward those who have diabetes or other needs to avoid sugar. Please note that I have had Type 1 Diabetes for 45 years, so my post was written with a thorough knowledge of what it’s like to have diabetes and have to navigate through the maze of artificial sweeteners because that’s your only option. The belief that people with diabetics must use a chemical sweetener is, quite frankly, a myth. The use of chemical sweeteners is a choice that is not made necessary by health issues. I’ve lived this lifestyle longer than many of you have been alive. I bake and cook without using any chemical sweeteners and still maintain an A1C of less than 6.0 and blood sugars consistently under 100. It can be done, but only if the person chooses to. Switching from chemical sweeteners to more natural alternatives such as Stevia is probably best done in stages. Even tiny changes on a daily basis soon add up to huge changes. I find that carrying Stevia with me at all times makes it easy to avoid the chemical sweeteners. My choice when I’m without my Stevia is Saccharin. It’s been around the longest and has the fewest side effects. The studies done showing it was a carcinogen were done by feeding the rats the equivalent of 10,000 cans of diet soda. I figure one packet on a very occasional basis is fine. I am so sorry I didn’t include my personal need to avoid sugar in my post. That would have clarified things and I do apologize! Have a great weekend!


Hi there, like I said, I found your post interesting, and I appreciate a different perspective than my own. I also didn’t mean to sound offended in my post, and I wasn’t suggesting that because I have lived with a diabetic for 24 of my 27 years, I know everything about sweeteners.  At the same time, I have real difficulty with the science that you offered and felt the need to speak out against what I view as misinformation. To be more specific, sucralose is legal in my own country, Canada. The Canadian food inspection  agency has much stricter guidelines than the FDA does in the USA, we don’t have certain synthetic products available at all (such as olestra and even saccharin  which we now know is safe was banned for about 25 years in Canada). Yes, I think it is perfectly possible for a diabetic to not use synthetic sweeteners, my mother (who is a very healthy diabetic, with A1C’s that are on target, who regularly exercises, and at the age of 55 has no complications)  consumes maybe one-two beverages per week which are sweetened with aspartame, and the rest of the time uses a lower glycemic index sweeter (like brown rice syrup in baking) or nothing at all (in tea). But, I think that synthetic sweeteners are incredibly important tools to people adjusting to the diabetic diet, as avoiding sweets and changing your diet is a ton of work and it is a heck of a lot better for a diabetic to drink a diet coke rather than a regular loaded with 30 tbs of sugar. Trust me, my paternal grandmother lost toes and died of a stroke way too young because she continued to consume large quantities of sweets long after being diagnosed with type two diabetes. Those people should not be scared off from using synthetic sweeteners with what basically amounts to pseudo-science. (Dr. Mercola is one of the most dubious sources around, his website focuses on shilling products rather than science, and  he has almost been stripped of his title three times by the college of physicians and surgeons. Once, because he claimed sunscreen was more likely to cause cancer than overexposure to the sun.)

I am not diabetic; but rather sugar intolerant.  Lets just say that I am like a child all hopped up on their Halloween candy….I get REALLY hyper (including racing heart) for about 10-15 minutes and then I CRASH HARD.  It then takes me DAYS to recover from the sugar hangover. I eliminated sugar from my diet 2 years ago and over that two years I have experimented with different sugar substitutes.

For some reason or another most artificial sweeteners do weird things to my body and blood sugar.  Sugar alcohols, which are in most “no sugar added”/”sugar free” food stuffs – actually make me ill.  Ill as in: blood sugar so low that I shake, get confused, irritable.

Agave nectar and I are on speaking terms, but we are by no means close. It causes problems with my blood sugar too.

Stevia and I get along well.  And because of this, it is the only sweetener I use when I bake and cook.

Not to be too nitpicky here, but you mentioned that chlorine is the poison added to sugar to make sucralose and you say that chlorine occurs only in chem labs but chloride is natural.  However, in your synthesis explanation you list two sources of chloride but no actual chlorine.  This does not make sense.

I’m not a big fan of Splenda or any other artificial sweeteners, but anytime someone talks about one molecule being so similar to another molecule (the only difference is one or two atoms!!) I start smelling a fish.  After all, the difference between water and peroxide is just an oxygen atom.  Is water *really* that good for you??

Just because something has “chemicals” in it, doesn’t mean it’s unnatural and going to kill you.  PS – *everything* has chemicals in it.


On a similar note; every day, billions of people ingest poisonous chlorine chemically combined with a metal that reacts explosively with water! This substance is added to just about all the processed food you eat, and is even present in small amounts in so-called ‘organic produce’!! Take action!!!! Boycott natrium chloratum!!!!!!!1

I’m very allergic to aspartame, saccharine, and sucralose. Like, hives and anaphylaxis allergic. So artificial sweeteners of any kind can kill me, pretty much. Here’s a fun game: try to find toothpaste, mouthwash, liquid medicine, gelcap medicine, gum, breath mints, or tooth whitener without artificial sweeteners. It’s Tom’s of Maine, Altoids, and old-school tablet medicine for me.

Of course, nothing on the Internet should be construed as medical advice, and if you have sensitivity to any substance, rather than relying on someone else’s biased anecdote, you should consult a medical professional and then follow their recommendations. Of course.

I use Sweet ‘n Low simply because my mom has used it in her coffee for as long as I can remember and I prefer the taste of it to the other artificial sweeteners I’ve used when at a coffee shop or a friend’s house. (And I have to admit that I didn’t know what the ingredients were until I Googled it just now.) And I’m sure that some of what I eat has other artificial sweeteners in it too; my mom is pretty sensitive to aspartame (she gets migraines that are triggered by certain foods, mostly those with nitrates) but I’ve never noticed any negative effects from whatever sweeteners I’ve consumed.

I used to be a big Splenda user and then we switched to Truvia. I was using Agave for a while, too.  Sometimes I think that aspartame gives me a headache, but I’ve never been able to decide for sure because sometimes I think it doesn’t.  All in all I know I should limit my consumption of artificial sweeteners (and real sugar for that matter).  I’ve been cutting out diet soda, but haven’t really noticed any difference in how I feel.

I know sucralose and aspartame gives me killer migraines when I consume large amounts of them. By large, I mean about four beverages with it; so when I would drink my mother’s sweet tea made with sucralose throughout the day, I found myself having more migraines than usual. Stopped with the sucralose, stopped having frequent migraines. I know the studies are inconclusive about the effects of aspartame and brain chemistry, but my mom was having bouts of amnesia, disorientation, chronic headaches, and confusion after years of high sucralose consumption; when she quit consuming it, all those problems stopped. I know anecdotal evidence doesn’t mean much to science (I am a researcher, too, after all), but with all the people claiming to experience these effects and me myself having experienced them, it’s hard for me to say there’s no effect there. From a cursory search via my institution’s journal databases, most of these studies claiming there is no effect aren’t longitudinal; how could they be, when the chemical hasn’t been out for too terribly long, and concerns have only recently been raised? We will be better able to tell when we track the effects of artificial sweeteners over longer periods of time.

I appreciate you sharing your views with us on sweeteners. My perspective is a tad different however, my Mother has been a type 1 diabetic from the time she was eight years old, and consequently has been consuming non-nutritive sweeteners for years. Sucralose (splenda), however, is slightly nutritive, enough to change the blood sugar of a type one insulin dependent diabetic and consequently is out of the question for my Mum. However, she does use aspartame (which was also the target of a lot of negative propaganda about five years ago until it became widely known that is it metabolized as a protein and does not release arsenic into the bloodstream). I have a problem with assertions about the toxicity of any of these sweeteners, however, as they are rigourously tested by both the Canadian and American governments. In fact, here is the official statement from the Canadian diabetic association which covers toxicity as well as glycemic index (stevia at least in Canada is still undergoing clinical trials for use by diabetics) Anyways, I have a huge problem with the attack of artificial sweeteners because diabetics (particularly ones with less control over their bloodsugar or who are not still excreting a small amount of insulin) require them. For that population, which my mother is part of, sugar is way more dangerous in both the short and long term for diabetics than artificial sweeteners, science has proven this, heck, the number of diabetics who are either dead or really sick (blindness, stroke, heart problems, lost limbs, you name it)  from years of running high blood sugars proves this. I just wanted another perspective to be heard.

And for me, as a chronic migraine haver, the shit is a life killer. All depends on body chemistry. What works for one doesn’t work for all. I’m not sure EVERYONE should NEVER use Splenda (absolutes are bad science… you can’t even say that for arsenic, as there are illnesses that require arsenic as a treatment, so…), but I don’t think it’s bad to talk about the negatives of something that’s often touted as a cure-all for those who want something sweet without the caloric effects.

I agree that it should not be touted as a cure-all. As someone with chronic digestive issues I find aspartame (maybe because it’s a protein and certain types of proteins give me trouble anyways) rather hard to digest. But, when I read really negative press about artificial sweeteners (which rarely seems super grounded- though this is one of the better articles I have read),  I worry about fear mongering and the larger diabetic community.  Both the CDA and the Canadian government (we are paternalistic like that here in Canada) released public statements on the safety of aspartame following that whole email forwarding aspartame myth in the early 2000’s because so many diabetics were avoiding it, choosing sugar instead.

(I know I keep talking about aspartame but I feel like it is comparable in how it is received as a diet food, a tool for diabetics, and then a potential poison… also, I have little to no experience with splenda personally as it’s not something I buy, nor is it something we had in the house when I was growing up.)

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