Sucralose side effects: All You Need To Know.

Last Updated on September 2, 2023 by Marc Seward

Medically Reviewed by Dr. Sumreen Anwar
MBBS, B. Sc , M. Phil – Reviewed & Approved on October 27, 2018
–Written by Angela Deckard

What is Sucralose?

People rejoiced when sucralose, sold under the brand name Splenda hit the market. For years people had been trying to find a sugar substitute without negative side effects or potential health hazards.

After several studies have linked sweeteners made with aspartame to cancer, everyone was relieved when Splenda came around, a seemingly harmless sugar substitute.

However, since it has been approved by the FDA in 1998, reports and studies have surfaced about sucralose’s negative side effects.

Sucralose has been deceptive from the start: marketed as a more natural alternative sweetener derived from sugar itself, sucralose is actually just chlorinated sugar.

When it accumulates in our bodies, chlorine can be harmful and a major threat to our health.

Not So Good for your Diet

Some people may turn to artificial sweeteners like sucralose when they are trying to eliminate sugar from their diet, but still desire sweets.

Products like Splenda offer big promises: the ability to enjoy a sugar derivative without negatively affecting your health.

The awful truth is artificial sweeteners like sucralose actually increase your chances of obesity by decreasing your body’s ability to eliminate calories.

Studies have found that consuming artificial sweeteners, including sucralose, has the following effect:

• Increases weight gain and fat storage
• Actually increases your appetite
• Increases cravings for carbohydrates

Because of this, sucralose is not regarded as a good option for people on a keto diet. While there is not much evidence that sucralose has an effect on blood glucose levels, there are definitely better alternatives for people following a ketogenic diet. We will look at the best alternatives later in the article.

Unfortunately, it seems that consuming sugar itself is actually less detrimental to your health than certain artificial sweeteners.

Sugar is in no way good for your health or your weight loss goals, but it is certainly the lesser of two evils.

The Side Effects of Sucralose

It takes time for sucralose to build up in the system, so if you have eaten something made with sucralose once or twice, worry not. Our body is able to dispose of sucralose consumed sparingly. However, if you use sucralose daily, your body may not be able to get rid of it.

Research has found that your body can get rid of 96.7% of sucralose when consumed sparingly, however, with more consistent consumption; your body can only get rid of 92.8% of sucralose.

92.8% may still seem like a high number, but that 8% of chlorinated sugar remaining in your body gets stored in your body and accumulates, making your cells toxic.

It may seem surprising that the FDA would approve something that is clearly so toxic, however, the FDA has a history of approving several things that have later been pulled off the market for being harmful.

The truth is, FDA testing of a product is not always so rigorous and often provided by companies that have a financial interest in the product.

Suffice to say, the studies often conducted are short-term and often skewed in the favor of the interested party. These short-term studies barely skim the surface and do not examine the effect sucralose may have on the liver or kidneys.

Below are some of the side effects associated with that little yellow packet.

1) Digestion

Consuming sucralose may have a detrimental effect on your digestion. Studies have shown that artificial sweeteners can wreak major havoc with your digestion, causing diarrhea, gas, and bloating.

Splenda may act as a laxative because it alters the bacteria in your gut, particularly the good bacteria. Good bacteria in your gut ensures that the digestion process goes smoothly while minimizing the amount of gas production while breaking down food.

However, when sucralose is thrown into the mix, the levels of nitrogen gas and water potentially increase in your colon, possibly leading to such nasty side effects as diarrhea.

2) Disrupts your Intestinal Flora / Gut Bacteria

More and more we are finding out that maintaining a healthy gut flora can be the key to so many aspects of general health. So new dietary advice is beginning to emerge on how to improve your gut flora. The bad news is that sucralose may damage and unbalance the good to bad bacteria balance.

Several studies have found that sucralose may have a negative effect on the balance of your intestinal bacteria. One animal study found that consuming sucralose decreased the good bacteria in your digestive tract while increasing bad bacteria in your stool.

A study done on rats demonstrated that sucralose can have a negative impact on the gut’s friendly bacteria. The animals that were fed sucralose for 12 weeks had between 47 and 80% less anaerobes in their gut.

The researchers also found a significant decrease in the amount of beneficial bacteria such as lactic acid bacteria and bifidobacteria while harmful types of bacteria were not affected. What is more, the bacteria had not returned to its normal levels when the animals were tested 12 weeks later. You can read an abstract of the study here.

There are currently no studies indicating that this would have a similar effect in humans, however, it is something to consider.

3) Prevents Absorption of Medication

Consuming sucralose may inhibit the proper absorption of certain medications, decreasing their potency. These drugs include medications for heart disease and cancer.

4) Headaches

A study released in 2008 that artificial sweeteners may be responsible for triggering nagging headaches. This artificial sweetener lineup includes sucralose.

This study indicates that consuming artificial sweeteners may cause mild side effects such as headaches, and possible even migraines.

However, more studies need to be done in order to determine how artificial sweeteners affect people that are susceptible to migraine headaches.

5) Insulin Response and Diabetes

How much impact sucralose has on blood glucose and insulin levels remains a controversial topic. There are very few studies into the impact of the sweetener on blood sugar levels but there are some indications that ii may have a negative effect.

A study published in the Diabetes Care journal found that consuming sucralose may alter the way your body responds to sugar. This and similar studies have prompted some people to suggest the sweetener is not suitable for people with diabetes or pre-diabetes.

However, the impact of sucralose on blood sugar may well depend on each individual and whether or not you are used to using artificial sweeteners.

One small scale study, published in 2013, looked at the effects of sucralose on 17 very obese patients. The researchers found that sucralose had a much greater negative effect on those who rarely used artificial sweeteners.

A number of other studies have failed to demonstrate that sucralose negatively affects insulin and blood sugar levels in healthy people of a normal weight who consumed sucralose on a regular basis.. (1) (2)

It would appear that those who consume the sweetener more often are less at risk of negative blood sugar or insulin changes.

6) Allergies

Some people have reported that consuming sucralose has led to a host of symptoms resembling an allergic reaction. The most common symptoms observed after consuming sucralose within a 24-hour time frame are:

Rashes or hives on the skin. Some people have reported blistering, itching, redness, and swelling
Acne
Swelling of the lips, tongue, throat, and eyelids
Bleeding gums
Shortness of breath, including wheezing and coughing
A runny nose and sneezing
Bloodshot, watery eyes
Heart palpitations
Achy Joints
Nausea, bloating, gas, or diarrhea
Tinnitus
Dizziness
Anxiety or depression

7) Inflammation

When it comes to the potential effects of sucralose, this is another controversial topic, So does sucralose cause inflammation?

According to recent animal studies, it very well may. In a study, published in 2018, researchers found that while sucralose did not have a negative impact on animals without Crohn’s disease, it did have a marked, negative effect on the mice with the disease. Being fed sucralose led to an increase in E.coli as well as the levels of bacteria found in the intestinal wall. This led to inflammation in the gut.

According to the study’s lead author – Dr. Rodriguez Palacios :

“Our findings suggest that patients with Crohn’s disease should think carefully about consuming Splenda or similar products containing sucralose and maltodextrin.”

8) Other Side Effects

Consumer complaints against Splenda have been numerous. These reports have included such side effects as:

• Blood sugar spikes
• Digestive problems
• Weight gain
• Seizures
• Dizziness
• Blurred vision

Weight gain sounds counterintuitive-but the research is very mixed on whether Spenda actually helps with weight loss. One meta analysis found no difference in weight between those using artificial sweeteners and those using regular sugar. With some studies showing slight weight loss and others slight weight gain from using artificial sweeteners.

Some studies suggest that consuming artificial sweeteners leads to higher rates of dementia and stroke.

Sucralose and Cancer

On top of the other side effects already mentioned in this article, there has recently been quite a bit of controversy following Italian research into potential cancer-causing effects of sucralose. (1)

The research has come under fire from numerous quarters including unsurprisingly the manufacturers of Splenda itself.

The research which was conducted at Bologna’s Ramazzini institute encouraged advocacy groups to increase warnings regarding sucralose from caution to avoid.

The study which was conducted on nearly a thousand mice suggests that mice fed with sucralose were at a significantly greater risk of developing blood-related cancers including leukemia.

However, the reception to the research has been mixed, to say the least.

It goes without saying that research conducted on mice does not necessarily mean that the same effects will occur in humans but it is also worth mentioning that the mice involved in the experiment were given in the region of four times the quantity of sucralose that is currently deemed safe for human consumption.

The study certainly caused a number of scary headlines but there have been plenty of critics eager to point out that the research went against the results of numerous previous studies.

It is also worth noting that the same Ramazzini Institute found a link between aspartame and cancer in 2012 and that many regulatory authorities including the European Union were unmoved by the results.

In fact, the European Union concluded that the rodents involved in the study may well have had cancer before the study began.

Critics of the research point out that studies conducted at the Ramazzini Institute have been unreliable and that they fail to observe international standards for design and safety.

While there is little agreement regarding the carcinogenic potential of sucralose, most experts do agree on one thing. We need to keep an eye on the effects of sucralose and artificial sweeteners to ensure that they are safe in the long term.

Human Studies into Sucralose Safety

There have been very few human clinical trials into the safety of sucralose or Splenda and only two trials were ever published prior to the FDA approving the stuff for human use. Those two trials actually involved 36 human subjects.

Yes, you heard that right…before approving sucralose, there was a grand total of 2 completed studies involving 36 participants. But that is not all…the longest completed and the published trial lasted all of four days and actually examined the effect of sucralose regarding tooth decay rather than any other human tolerance issues.

While the FDA is not lying when they tell you that they have reviewed more than a hundred studies on Splenda, they fail to tell you that the vast majority of these studies were conducted on animals rather than humans. The results of these animal studies indicate that there are plenty of potential issues including the following potential problems.

A decrease in red blood cell count and signs of anemia.
High doses caused an interference with the production of sperm and led to infertility.
Brain lesions occurred when sucralose was given to animals in high doses.
Rats fed with sucralose exhibited enlarged or calcified kidneys which the FDA determined was
insignificant.
Rabbits fed with sucralose experienced significantly greater spontaneous abortions.
Rabbits given sucralose also suffered a far higher mortality rate compared to control group
animals.

Using Artificial Sweeteners during Pregnancy and the Risk of Infant Obesity

If you are pregnant and you are using artificial sweeteners then it is certainly worth taking a look at some recent research into its potential effects on your child.

Using Artificial Sweeteners while Breastfeeding

As well as potentially increasing the risk of obesity for your unborn child, studies have demonstrated that consuming artificial sweeteners like sucralose, aspartame, and saccharin may be damaging to a breastfed baby.

Only saccharin is considered unsafe during pregnancy or lactation but a study published in 2015 found that sucralose was also present in breast milk. The study which employed 20 breastfeeding mums collected breast milk samples and found that both saccharin and sucralose were present while no aspartame was detected.

The results demonstrate that artificial sweeteners can easily find their way into an infant’s diet but up to now the implications are unknown.

Given the results of the two studies cited above, it would seem prudent to remain on the safe side of the fence and avoid using artificial sweeteners like sucralose during pregnancy and while breastfeeding.

Further Research Into How Artificial Sweeteners may cause Weight Gain in Adults

Researchers are still uncertain of the precise links between weight gain in adults and the consumption of artificial sweeteners. Observations, however, have led experts to believe there may be a link and researchers have hypothesized several ideas regarding potential links.

Firstly weight gain may occur due to changes in the way glucose is metabolized.

Secondly, weight gain may be caused by an alteration in the gut microbiota. This study published in 2014 demonstrated that consuming artificial sweeteners could cause glucose intolerance because of the disruption in the intestinal microbiota.

Thirdly researchers believe that the consumption of artificial sweeteners disrupts appetite control and the ability to regulate calorific intake. According to research published in 2011, rat models showed that the consumption of artificial sweeteners reduced the ability to distinguish between sweet tastes and impaired the ability to regulate intake of sweet and high calorie or high-fat food.

Where Can Sucralose be Found?

You’ve probably seen those little yellow packets of Splenda on restaurant tabletops and at your local coffee shop. It is easy to avoid by simply not adding it to your food and drink.

However, sucralose can be lurking in your food and drinks without you even knowing it. Processed food manufacturers often add sucralose to their food and soft drinks during production.

Sucralose is even sold in bulk to drug companies as an additive to certain medicines. Unfortunately, sucralose is not listed on drug information, so it may be unclear whether or not you are consuming it. It is important to monitor the food, drinks, and medications you take.

If you are consciously avoiding sucralose and any other artificial sweetener, but find that you are still suffering from the known sucralose side effects, start researching the ingredients of your medications and the foods and drinks that make up your diet.

Avoiding diet soft drinks (better yet soft drinks altogether) and processed food is one way to ensure that you are completely abstaining from harmful additives and toxins. Other products that are known to contain sucralose: health bars, baked goods, juices, and chewing gum.

Check everything–protein powders, “low sugar” instant oatmeal and other things supposedly healthy are often loaded with them.

Sucralose Alternatives

So now what? Your alternative to sugar has proven to be more harmful than sugar itself, but you still have that sweet tooth. It is hard. Sugar is addicting, and giving it up is not as easy as it seems.

Sugar withdrawals are tough, causing actual physical and emotional side effects. Although more testing needs to be done on the long-term effects of sucralose, the fact that it is basically chlorine added to sugar is straight up toxic to your health.

As it turns out, there is actually a more natural alternative to sugar, free of harmful chemicals. Whole Leaf Stevia, for example, is a great way to satisfy your sweet tooth without poisoning your body. Stevia can be substituted is most drinks and dishes sucralose and sugar are used in.

You may see Rebaudioside A or Reb A listed as a sweetener (typically in soft drinks). This sweetener is made from a steviol glycoside that is over 200 times sweeter than sugar.

If you would like to avoid using artificial sweeteners altogether, raw local honey is another solution. Although honey does contain calories it also has a number of health benefits. Using small amounts in tea are is not going to significantly add calories.

Another alternative may be Xylitol. Xylitol is a sugar alcohol found in some chewing gums and in some toothpaste. Xylitol has the benefit of being good for your teeth—as it (somewhat selectively) kills bad bacteria in the mouth.

What are the Best Sweeteners for a Low-Carb Keto Diet?

Low- carbohydrate diets are becoming increasingly popular and many people are looking for an alternative sweetener that will work on their diet and satisfy their sweet tooth. There are certain requirements for a sweetener to be keto-friendly :

Low Glycemic Index : For a sweetener to work on a keto diet, it needs to have a low GI. The lower the better with the closer to zero representing the best choice.
Sugar and Carb Free : Avoiding sugar is key to the keto diet. The body needs to burn its fat for energy rather that carbs, Even most fruit should be limited or avoided. To keep your body in ketosis, alternative sweeteners are necessary.

Here are the 3 best sweeteners for those of you following a ketogenic diet like Atkins.

Stevia

Stevia is one of the very best artificial sweeteners full stop but also a great option for people on a low-carb diet. Stevia is extracted from the Stevia rebaudiana herb and contains zero calories, zero carbs and rates a big zero on the GI index. It is also some 200 to 300 times sweeter than regular sugar so you only need a little.

Stevia has other health benefits. It helps reduce both blood sugar levels and insulin following a meal and also contains antioxidants like quercetin and apigenin.

Erythritol

If you are following a low-carb diet, erythritol is another good choice. This sweet tasting substance is found naturally in a number of fruit and vegetables and when used in moderation appears not to have any negative effects.

Erythritol is extremely low in calories and has a GI of zero but is not as sweet as regular table sugar. When buying erythritol, make certain it soes not contain any additives that could affect your blood sugar and carbohydrate count.

Monk fruit

While those on a keto diet need to avoid many fruits, the sweetener made from monk fruit is an exception. This sweetener is becoming more popular because of its natural, low-calorie sweetness that does not cause pikes in blood sugar and insulin.

Monk fruit is an ideal choice for people following a low-carb diet. It scores zero on the GI and might even help stabilize blood sugar. It does not leave a bitter aftertaste and like stevia, is some 300 times sweeter than regular sugar.

Monkfruit gets its sweetness from compounds called mogrosides. research has demonstrated that these compounds can inhibit the growth of pancreatic cancer tumors.

If there is a downside to monkfruit, it is more expensive than stevia and erythritol.

2018 Research

A 2018 Meta-analysis summed up the latest data regarding risks vs benefits in non-calorie sweeteners–for both humans and animals:

RISKS VERSUS BENEFITS OF THE USE OF ARTIFICIAL SWEETENERS

The table shows that the more recent studies from 2013-2017 have found more risks than benefits. More recent studies also have more human studies. More research will need to be done but right now there does not seem to be a reason to use artificial sweeteners –especially when some natural alternatives are available.

Updated Research From 2019 : Effects of Sucralose on Gut Microbiota

We mentioned earlier in the article that there are concerns about the effects artificial sweeteners like sucralose can have on the composition of bacteria in the gut. A review of the relevant studies was published early in 2019. review looked at the effect of various artificial and natural sweeteners on the composition of the microbiota in the gut.

The composition of bacteria in the gut plays an important role in disease prevention and human health. The so called intestinal microbiota plays a significant role in metabolism and immune health and can be altered rapidly by dietary changes. According to experts, the well-known relationship between diet, health and intestinal microbiota makes it essential to learn more about the effects of sweeteners on the microbiome.

According to the review, sucralose and saccharin have so far been found to affect the composition of gut microbiota. Studies have found that the consumption of sucralose decreases the number of anaerobic bacteria, lactobacilli and bifidobateria. The abstract can be read here while the full review can be read by clicking the following link. https://academic.oup.com/advances/article/10/suppl_1/S31/5307224

Bottom line

As things stand, there is nowhere near enough evidence that artificial sweeteners like sucralose and aspartame can be safely consumed and it would appear to be best to avoid them entirely until their safety is proven one way or another.

For the time being, you would be far better off avoiding artificial sweeteners entirely and if you have a sweet tooth going down a more natural route.

The potential risks are not worth it based on what we know today. Especially if you are pregnant or breastfeeding–these latest studies are a bit scary, to say the least.

Your best bet is to stick to more natural versions–below are some good options:

Lakanto has a nice brown sugar taste–it is a mix of Monkfruit and Non-GMO erythritol. It is my pick as the best option no calorie sweetener.
Stevia is good but has a bit of an aftertaste that Lakanto does not.
Honey is a good option if you are not counting calories or worrying about impacting blood sugar or stay in ketosis.
Another option is coconut sugar, it has less of a blood sugar impact (35 Glycemic Index). It is still sugar and it has a lot of fructose which is processed in the liver.
Maple Syrup is another healthier (although not zero calorie) option
Jaggery is a type of brown sugar, it has calories but also has some health benefits.

Anything is bad in excess so cutting overall sugar consumption should be the priority. If you are adding a teaspoon in your coffee or tea–any of the above are potentially good choices.

(1) https://www.ncbi.nlm.nih.gov/pubmed/19221011
(2) https://www.ncbi.nlm.nih.gov/pubmed/20420761