Is Sucralose Bad for You? Side Effects, Foods and More - Dr. Axe

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Sucralose: 5 Reasons to Avoid This Artificial Sweetener

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Sucralose - Dr. Axe

Many of our friends and family members have been duped into believing that artificial sweeteners like Splenda® are saviors to prevent diabetes and obesity. However, the health risks associated with the ingredients in Splenda, or sucralose, are extensive and downright troublesome. As research continues to investigate the details, more negative effects are surfacing.

Sucralose is one of the top artificial sweeteners that’s used globally in reduced-calorie and diet foods and beverages. Although it’s marketed as a better alternative for your figure, the health profile for sucralose has raised concerns among researchers, and the many sucralose side effects and dangers can’t be ignored.

Instead of grabbing those yellow packets of Splenda and turning to “sugar free” products in hopes of cutting calories, opt for healthier sugar substitutes that give your recipes a natural sweetness and provide antioxidants, vitamins, minerals and even fiber.

What Is Sucralose?

Sucralose is a chlorinated sucrose derivative. This means it’s derived from sugar and contains chlorine.

Making sucralose is a multistep process that involves replacing the three hydrogen-oxygen groups of sugar with chlorine atoms. The replacement with chlorine atoms intensifies the sweetness of sucralose.

Originally, sucralose was found through the development of a new insecticide compound. It was never meant to be consumed.

However, it was later introduced as a “natural sugar substitute” to the masses, and people had no idea that the stuff was actually toxic.

In 1998, the Food and Drug Administration (FDA) approved sucralose for use in 15 food and beverage categories, including water-based and fat-based products like baked goods, frozen dairy desserts, chewing gum, beverages and sugar substitutes. Then, in 1999, the FDA expanded its approval for use as a general-purpose sweetener in all categories of foods and beverages.

Facts on Splenda

The most common sucralose-based product on the market today is Splenda. It is one of the most popular sweeteners in the United States.

That’s probably because it’s about 600 times sweeter than sugar. Here are some general facts about Splenda that may provide cause regarding its use:

  • Splenda is a synthetic sugar that isn’t recognized by the body.
  • Sucralose only makes up about 5 percent of Splenda. The other 95 percent contains a bulking agent called maltodextrin, which serves as filler, and corn-based dextrose, a type of sugar.
  • Splenda is used as a sugar substitute in cooking and baking, and it’s added to thousands of “zero calorie” food products sold throughout the United States.
  • The calorie content of Splenda is actually 3.36 calories per gram, which comes from the dextrose and maltodextrin.

Data shows that across the globe, the range of product utilization for sucralose is more extensive than for any other artificial sweeteners.

Why is sucralose so popular for use in our foods and drinks? It’s readily soluble in ethanol, methanol and water.

That means it can be used in both fat- and water-based products, including alcoholic drinks.

Other artificial sweeteners, like aspartame and sodium saccharin, aren’t as soluble. Therefore they have more limited product applications.

Side Effects and Dangers

1. May Cause Diabetes

A study published in the journal Diabetes Care discovered that if you consume sucralose, the risk of developing diabetes is profound. According to the study, daily consumption of diet soda was associated with a 36 percent greater risk of metabolic syndrome and a 67 percent greater risk of type 2 diabetes.

That means sucralose is among the unexpected diabetes triggers. So if you’ve been wondering about the safety of sucralose for diabetes, the clear answer is to be careful — it actually increases your risk of this serious condition.

Researchers evaluated this phenomenon for the first time with human subjects. Seventeen obese individuals who were insulin-sensitive took oral glucose tolerance tests after consuming either sucralose or water. 

In addition to revealing that there was an “increase in peak plasma glucose concentrations” after consuming sucralose, it was discovered that there was a 23 percent decrease in insulin sensitivity, which prevents glucose absorption in cells.

A more recent 2020 study published in Cell Metabolism found that the consumption of sucralose in the presence of a carbohydrate rapidly impaired glucose metabolism and resulted in the dysregulation of gut-brain control of glucose metabolism. A 2023 study also revealed that long-term sucralose consumption “induces hepatic insulin resistance.”

2. Increases Risk of Irritable Bowel Syndrome and Crohn’s Disease

Several years ago, researcher Xin Qin, M.D., Ph.D, from New Jersey Medical School found that consuming sucralose causes IBS symptoms, ulcerative colitis and Crohn’s disease. Dr. Qin made this discovery when examining the rapid increase of IBS among Alberta, Canada residents over a 20-period. In short, it went up 643 percent.

This led Qin to conduct his study. What did he find? 

Sucralose has a more detrimental effect on gut bacteria than other artificial sweeteners, such as saccharin, because 65 percent to 95 percent of sucralose is excreted through feces unchanged. In 1991, Canada became the first country in the world to approve the use of sucralose as an artificial sweetener. In other words, there was a direct correlation between the amount of sucralose consumed and the increase in inflammatory bowel disease.

A recent study published in Inflammatory Bowel Diseases indicates that the use of artificial sweeteners like Splenda doubles the risk for Crohn’s disease and can exacerbate antimicrobial intestinal reactivity in individuals with Crohn’s and other pro-inflammatory conditions.

To answer some common questions concerning the safety of sucralose and digestion — does sucralose cause bloating? It certainly can, as it’s been linked to serious pro-inflammatory conditions that affect your digestive system.

Does sucralose make you poop? Again, it can increase inflammation and cause IBS symptoms in some cases.

Sucralose - Dr. Axe

3. Linked to Leaky Gut

Does sucralose affect gut bacteria? Essentially, the understanding we now have is that because the body cannot digest sucralose, it travels through the human gastrointestinal track and damages it as it goes. It harms the intestinal wall, potentially causing leaky gut.

Several studies have confirmed the harmful effects of sucralose on gut health. For instance, the Journal of Toxicology and Environmental Health published an animal study out of Duke University Medical Center describing that Splenda not only significantly reduces beneficial bacteria in the gut, but it also increases your fecal pH. That decreases the amount of nutrients you can absorb.

4. May Generate Toxic (and Carcinogenic) Compounds When Heated

A study published in the Journal of Toxicology and Environmental Health found that cooking at high temperatures with sucralose can generate dangerous chloropropanols, a potentially toxic class of compounds. Although sucralose is commonly used in baked goods, studies show that the stability of the artificial sweetener decreases as the temperature and pH increase.

Not only does sucralose undergo thermal degradation when it’s heated, but researchers also found that chloropropanols that comprise a group of contaminants, including genotoxic, carcinogenic and tumorigenic compounds, are generated.

The researchers of the study published in Food Chemistry concluded that “caution should be exercised in the use of sucralose as a sweetening agent during baking of food products containing glycerol or lipids.”

If you’re wondering if sucralose can cause cancer, this is some concerning information, especially because sucralose is commonly used in baked goods and other food products that are heated. More research is needed for concrete evidence about the carcinogenic effects of sucralose.

5. Associated with Weight Gain

Thought using sucralose in your coffee was going to help you lose weight? Well, it turns out that epidemiological studies in humans and lab studies in animals both suggest an association between using artificial sweeteners and body weight gain.

Plus, artificial sweetener use can increase the risk for metabolic syndrome, type 2 diabetes, hypertension and cardiovascular disease. These studies didn’t evaluate the effects of sucralose, specifically, on weight gain, but there are studies that indicate that sucralose doesn’t appear to help with weight loss.

In an 18-month trial published in the New England Journal of Medicine, 641 children (477 completed the study) were randomly assigned to receive an eight-ounce can per day of either a no-calorie sweetened or sugar-sweetened beverage that contained 104 calories.

The sugar-free beverage contained 34 milligrams of sucralose, along with 12 milligrams of acesulfame-K. By the end of the study period, the calorie consumption from these beverages was 46,627 calories greater for the children in the sugar-sweetened group than in the sucralose-sweetened group.

However, the total weight gain over the 18-month period was only one kilogram greater for children in the sugar-sweetened group. Researchers cannot explain the small difference in weight gain given the significant difference in caloric consumption from beverages.

Another study involving adolescents showed no consistent reduction of weight gain two years after families were supplied with artificially sweetened beverages in order to reduce their consumption of sodas sweetened with sugar.

So does sucralose cause weight gain? Well, we know that in many cases it doesn’t help with weight loss, and for people who use it in their cooking, baking and coffee strictly to watch their calorie count, this really doesn’t seem to be an effective weight-loss method.

There have been reports of adverse reactions to sucralose and products made with Splenda, including headaches and allergic reactions. Plus, recent research indicates that consuming sucralose can negatively impact your gut health and even cause metabolic syndrome.

If you tend to use sucralose because it’s a no-calorie option and you’re trying to lose weight, know that studies show artificial sweeteners like Splenda do not appear to help with weight loss. Instead, opt for natural sweeteners that are lower in calories instead.

Raw honey and stevia are just two excellent options.

Foods and Uses

Sucralose, or Splenda, is used in many food and beverage products that are marketed as healthier options. Sometimes, you wouldn’t even know that sucralose is in the bottled beverage or packaged food that you pick up from the grocery store.

It’s even found in toothpastes, lozenges and vitamins.

The best way to determine whether or not sucralose is used in a product is to check the ingredient label. Sometimes the box or bottle of a product says right on the front that it’s made with Splenda.

Often, products containing sucralose are labeled as “sugar free,” “sugarless,” “lite” or “zero calorie.” Look out for these slogans because they usually indicate that some kind of artificial sweetener is used in the product.

Here are just some of the products that contain sucralose:

  • Some diet sodas
  • Some sparkling waters
  • Diet iced tea products
  • Some juice products
  • “Sugar free” sauces, toppings and syrups
  • Chewing gum (including “sugarless” products)
  • “Diet,” “fat free” and “no sugar added” cocoa mixes
  • Some protein and diet bars, powders and shakes
  • Many “sugar free” baked goods
  • “Sugar free” ice-pops and ice cream
  • “Lite” and “no sugar added” ice cream products
  • Some popcorn products
  • “Sugar free” and “light” yogurt products
  • “Sugar free” or “light” hard candy
  • “Sugar free” chocolates
  • “Sugar free” mints and lozenges
  • Some toothpastes
Sucralose foods - Dr. Axe

Is It Safe?

The quick answer to the common question “is sucralose safe?” is no. From metabolic syndrome to digestive problems and weight gain, sucralose doesn’t do you any favors. In fact, it impacts your health negatively in a number of ways.

What are the side effects of sucralose? To reiterate the many sucralose side effects, they include:

  • alters glucose and insulin levels
  • increases risk of digestive problems
  • alters gut health and damages the GI tract
  • kills probiotics
  • may play a role in certain cancers
  • generates toxic compounds when heated
  • may lead to weight gain

Sucralose vs. Stevia vs. Aspartame

Sucralose

Sucralose is an artificial sweetener that’s used in “sugar free” and “sugarless” products. It’s marketed as a no-calorie sweetener that can help you lose weight — although studies suggest that this isn’t true.

Sucralose is added to many products in your grocery store, including:

  • baked goods
  • yogurts
  • ice creams
  • candies
  • diet sodas
  • sparkling waters
  • protein bars

Although the FDA has approved the use of sucralose in food and beverage products, including those marketed for children, there are some concerns regarding ingesting sucralose. Studies suggest that it’s linked to leaky gut and gastrointestinal problems like IBS and Crohn’s disease.

It may even cause diabetes, although it’s commonly marketed as a “sugar free” agent that’s better for people on a diabetic diet.

Sucralose vs. Stevia

Stevia is an edible herbal plant that’s been used for more than 1,500 years. Unlike sucralose and aspartame, it is a natural sweetener.

Stevia extracts are said to be about 200 times sweeter than sugar. Although it can be used in your morning coffee or smoothie in place of sugar, stevia does not cause the dangerous side effects like most artificial sweeteners.

In fact, it may have anticancer, antidiabetic, cholesterol-improving and weight loss-promoting properties.

There’s a telling study that compares the effects of stevia, sugar and alternative sweeteners on food consumption, satiety and glucose/insulin levels after eating. The research, published in the journal Appetite, took 19 healthy, lean people and 12 obese individuals between 18 and 50 years old and had them complete three tests in which they consumed stevia, sucrose (table sugar) or aspartame before eating lunch and dinner.

It’s no surprise that when these people consumed stevia, they didn’t feel hungry and overeat during their meals like they did when they consumed sucrose. Additionally, the researchers reported that “stevia significantly reduced post-meal glucose levels compared to those who consumed sugar or aspartame.”

In other words, they discovered that stevia helps normalize blood sugar levels and reduce your risk for diabetes compared to the blood sugar spike people experience when they drink sugary or diet beverages before, during or after meals.

Sucralose vs. Aspartame

Aspartame is an artificial sweetener that also goes by the more recognizable names Equal® and NutraSweet®. It’s found in a variety of foods and products, including:

  • diet soda
  • sugar-free breath mints
  • sugar-free cereals
  • flavored water
  • meal replacement products
  • sports drinks

Although companies that benefit from the popularity of aspartame have released studies touting its safety, 92 percent of studies funded independently indicate the artificial sweetener’s adverse effects. Some of the most serious dangers of aspartame include worsening (or maybe causing) diabetes, increasing the risk of heart disease, possibly causing brain disorders, worsening mood disorders, causing weight gain and possibly causing cancer.

Is sucralose as bad for you as aspartame?

Like sucralose, aspartame is approved by the FDA for its use in many foods and beverages. In fact, it can be found in diet soda and over 6,000 other products.

It’s also found in more than 500 over-the-counter drugs and prescription medications, even after the research on its dangerous side effects has been released.

Both artificial sweeteners have dangerous side effects and should be avoided. Instead, choose a natural sweetener like stevia for your coffee, baked goods or other recipes that need extra sweetness.

Related: Erythritol: Is This ‘Healthy’ Sweetener the Real Deal?

Healthier Alternatives

If you are looking for a healthier substance to add sweetness to your recipes, you don’t have to rely on artificial sweeteners. There are some excellent natural sweeteners that serve as tasty alternatives and don’t come with a list of potential side effects and dangers.

Here’s a quick rundown of some of the best alternative sweeteners out there:

  1. Stevia: Stevia is a natural sweetener that comes from a plant in the Asteraceae family. It’s been used for over a thousand years and is known as the “sweet herb.” Stevia is one of the best sweeteners for diabetics. It is heat-stable and can be used in baking, but remember that it’s about 200 times sweeter than table sugar, so a little goes a long way.
  2. Raw honey: Raw honey is a natural sweetener that’s loaded with enzymes, antioxidants, vitamins and minerals. One tablespoon has 64 calories, and it has a lower glycemic load than a single banana. You should not cook with raw honey, but it can be drizzled on yogurt, toast, salads or cereals for some extra sweetness.
  3. Maple syrup: Maple syrup nutrition has a higher antioxidant capacity than sugar, containing up to 24 different antioxidants. It’s also a source of manganese, calcium, potassium and zinc. Unlike sucralose, maple syrup is heat-stable and can be used in any recipe, including cookies, cakes, glazes and pancakes. Just opt for a product that’s 100 percent pure organic maple syrup and is labeled grade B or even grade C.
  4. Coconut sugar: Coconut sugar comes from the dried sap of the coconut tree. It contains trace amounts of vitamins and minerals. It also has short-chain fatty acids, polyphenols, antioxidants and fiber. You can use it in your favorite recipes as a sugar substitute because it measures just like table sugar.
  5. Blackstrap molasses: Blackstrap molasses is obtained from raw cane sugar. It’s made by boiling raw sugar until it’s a rich, sweet syrup. Unlike table sugar, blackstrap molasses is highly nutritious. Compared to refined sugar, rapeseed honey and dates, it’s proven to have the highest phenolic content and antioxidant activity. Blackstrap molasses can be used in baking or making marinades. It can also be combined with coconut sugar to make a brown sugar alternative.

Conclusion

  • What is sucralose, and is it bad for you? Sucralose is a chlorinated sucrose derivative that’s used as a sugar substitute because it contains no calories. Research shows that it’s an unhealthy option for people who are looking to use zero-calorie sweeteners.
  • The most common sucralose-based product on the market today is Splenda, which is one of the most popular sweeteners in the United States. Splenda is about 600 times sweeter than sugar.
  • Besides packets of Splenda, sucralose is used in a slew of foods and beverages, including diet sodas and other carbonated beverages, iced teas, ice cream, ice-pops, yogurts, baked goods, chewing gum, candies, and protein bars.
  • Recent research indicates that consuming sucralose has a number of dangerous health effects, including its ability to:
    • Potentially lead to diabetes
    • Increase your risk of IBS and Crohn’s disease
    • Possibly cause leaky gut
    • Generate toxic and cancerous compounds when heated
    • Make you gain weight
  • As such, it’s best to consume natural sweeteners instead, such as stevia, raw honey and maple syrup.

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