A single serving of Skittles contains 47 grams of sugar, roughly 12 teaspoons, which is nearly double the daily sugar limit recommended by the American Heart Association. Beyond the sugar, Skittles contain several synthetic dyes, acidic coatings, and other additives that raise legitimate health concerns, especially for children.
The Sugar Problem
Sugar is the most straightforward reason Skittles are bad for you, and the numbers are striking. That 47 grams in a standard 1.8-ounce bag isn’t just empty calories. The sugar in Skittles comes largely from corn syrup and high-fructose corn syrup, both of which are roughly 50% fructose. Your body processes fructose differently than other sugars, and the difference matters.
Fructose is metabolized almost entirely by the liver. Research published in Diabetes Care has shown that high fructose intake increases liver fat, visceral fat (the deep belly fat surrounding your organs), and triglycerides. It also raises total and LDL cholesterol while impairing your liver’s ability to respond to insulin. Over time, these changes contribute to nonalcoholic fatty liver disease and metabolic syndrome, a cluster of conditions that dramatically raises your risk of heart disease and type 2 diabetes. While most of this research focuses on sugary beverages consumed daily, the underlying mechanism is the same: your liver gets overwhelmed by fructose regardless of whether it arrives in liquid or candy form.
Synthetic Food Dyes and Behavior
Skittles get their rainbow of colors from synthetic dyes including Red 40, Yellow 5, Yellow 6, Blue 1, and Blue 2 Lake. These aren’t just cosmetic concerns. Evidence linking synthetic food dyes to behavioral problems in children, particularly hyperactivity and inattention, has been building for decades.
In 2021, California’s Office of Environmental Health Hazard Assessment completed a comprehensive review of all available studies and concluded that synthetic food dyes could “cause or exacerbate neurobehavioral problems in some children.” Red 40, the most widely used food dye in the U.S., can cause allergy-like reactions. Yellow 5, the second most common, triggers hypersensitivity reactions (primarily in people who are also sensitive to aspirin) and has been linked to hyperactivity in some children. Yellow 5 may also be contaminated with cancer-causing substances like benzidine.
The European Union already requires warning labels on foods containing these dyes, stating they “may have an adverse effect on activity and attention in children.” The U.S. has no such requirement, though legislative momentum is growing. California passed the Food Safety Act, which bans Red Dye No. 3 and several other additives from foods sold in the state starting in 2027. While Red Dye No. 3 isn’t currently in Skittles, the law reflects a broader shift toward scrutinizing the dyes that are.
Titanium Dioxide: Banned in Europe, Legal Here
Until recently, Skittles contained titanium dioxide (known as E171 in Europe), a white pigment used to give candy a bright, opaque appearance. The European Food Safety Authority reviewed the additive in 2021 and couldn’t rule out that it causes DNA damage, based on tests involving titanium dioxide nanoparticles. The EU banned it from food shortly after.
The FDA still permits titanium dioxide in food as long as it doesn’t exceed 1% of the product’s weight. The agency has argued that some of the European genotoxicity tests used materials and administration methods that don’t reflect how people actually consume the additive. However, a petition was filed in 2023 asking the FDA to revoke its approval, and that review is ongoing. Mars, the maker of Skittles, has been phasing titanium dioxide out of its recipe, though formulations vary by market.
Acidity and Your Teeth
Skittles have a pH of about 2.5, which is highly acidic. For reference, battery acid sits around 1.0 and pure water is 7.0. That level of acidity softens tooth enamel on contact, and the sticky texture of Skittles makes the problem worse by clinging to the grooves and surfaces of your teeth. This gives the acid and sugar prolonged contact time, creating ideal conditions for enamel erosion and cavities. Dentists specifically flag sticky, sour, and hard candies as the worst categories for dental health, and Skittles check two of those three boxes.
Hydrogenated Oils and Other Additives
Skittles also contain hydrogenated palm kernel oil, which serves as a texture and shelf-life ingredient. Partially hydrogenated oils are a source of artificial trans fats, which raise LDL (“bad”) cholesterol and lower HDL (“good”) cholesterol. This combination directly increases heart disease risk. While the FDA banned partially hydrogenated oils as a food additive in 2018, fully hydrogenated oils (which Skittles now use) can still contain small amounts of trans fat due to processing.
Carnauba wax, which gives Skittles their glossy coating, is a natural plant-derived wax considered safe for consumption. Citric acid, another key ingredient, contributes to both the sour flavor and the low pH that damages enamel. Modified corn starch, corn syrup, and sugar appear multiple times on the ingredient list in various forms, reinforcing just how sugar-dense the product is.
The Dose Makes the Difference
None of this means a handful of Skittles once in a while will cause measurable harm. The concern is cumulative exposure. A child who eats Skittles regularly is getting repeated doses of sugar that stress the liver, acids that wear down enamel, and synthetic dyes that may affect behavior and attention. Most people don’t eat just one serving either. A “sharing size” bag contains multiple servings, and it’s easy to consume the entire bag in one sitting, doubling or tripling the sugar and additive load.
What makes Skittles particularly worth scrutinizing isn’t that they’re uniquely dangerous compared to other candy. It’s that they concentrate several problematic ingredients into a single product: excessive sugar, multiple synthetic dyes, high acidity, and hydrogenated oils. Each of these carries its own well-documented risks, and in Skittles, you’re getting all of them at once.