The Green Page:
Why We Are Eating a Sunscreen Ingredient in Our Frozen Pizza:
If you have heard of titanium dioxide at all, you probably know it as an ingredient in
sunscreen. But it is also used in lots of foods, from pizza and salsa to frosting and candy
—and now, there is growing concern about the potential health risks of eating it.
The ingredient helps block the sun’s rays when we slather it on our skin at the beach.
Food makers use it to brighten up colours—think whiter mozzarella on your frozen pizza or more vibrant hues in your Skittles. Some research, mainly in animals, has suggested that eating it might be linked to immune system problems, inflammation and DNA damage that could lead to cancer.
The European Union has banned titanium dioxide in food since 2022. Earlier this year,
legislators in California introduced a bill to bar foods with titanium dioxide from being
served in public schools. Some public-health advocacy groups have petitioned the U.S.
Food and Drug Administration to not allow it to be used in foods.
What’s tricky:
It isn’t always easy to tell whether titanium dioxide is in your food. Manufacturers don’t have to list it by name on packages—it might be identified on a label only as “artificial colour.” But some do disclose it. And some food makers are reformulating products to remove titanium dioxide as questions about it grow.
The science isn’t conclusive. Some studies haven’t shown negative health effects, and
some countries, including Canada, Australia and New Zealand, have recently reviewed
the research and said that titanium dioxide in food is safe.
The Consumer Brands Association, a trade group that includes many food makers, says
titanium dioxide is used safely in certain foods as a colouring, noting that the industry
adheres to the FDA’s safety standards. Mars, which makes Skittles, says all ingredients it uses are safe.
Why titanium dioxide is in your food
In general, manufacturers add titanium dioxide to make products look more appealing. “A
very small concentration makes something look very white and bright,” said David Julian
McClements, a professor in the food-science department at the University of
Massachusetts Amherst. Adding it with other colours can make those colours pop, he said.
Titanium dioxide is often found in sauces, creamers and frostings.
Titanium dioxide is most prevalent in candy, coffee creamers and frosted or powdered
baked goods, said Kelsey Mangano, associate professor and nutrition program director at
the University of Massachusetts Lowell. The substance is also in many chewing gums
and mints.
It is a common ingredient in sunscreen because it is effective at blocking ultraviolet
rays. It is used in medications for a similar reason: to help protect the active ingredients inside the pill from being broken down or altered by light.
You don’t need to worry about it in sunscreen because there isn’t evidence that titanium dioxide penetrates the skin, said Nicolaj S. Bischoff, a PhD student at Maastricht University Medical Center in the Netherlands who has researched the possible health effects of titanium dioxide.
And since the substance performs an important function in medications, the risk/benefit calculus is different than with food, he noted.
What the science says
New higher-resolution microscopes and other methods of detecting and analyzing
particles are allowing researchers to better understand titanium dioxide.
Scientists now know that most titanium dioxide ingredients used in food contain varying
amounts of tiny nanoparticles. The problem with nanoparticles is that, because of their
small size, there is the potential for them to penetrate the mucous layer in your gastrointestinal tract, get into your cells and accumulate in your organs, said McClements.
Some animal studies found that consumption of titanium dioxide nanoparticles led to damage to the liver, immune and reproductive systems, and DNA. Other research
has found that titanium dioxide changes the gut microbiome and inhibits the growth of
beneficial bacteria.
New research in people has found a link between titanium dioxide consumption and
inflammation in the gut. In a small study with 35 healthy adults, those who had the highest
levels of titanium dioxide in their stool had higher levels of certain gut-inflammation
measures than those with the lowest titanium dioxide levels. They also had indications of
more gut permeability, or how “leaky or separated the cells are,” said Mangano, the study's lead scientist, published in February in the journal NanoImpact.
The concern is that chronic increased gut inflammation and permeability could increase
the risk of colon cancer, nutrient deficiencies and the low-grade inflammation that
underlies many chronic diseases, Mangano said. After conducting this research, Mangano said she stopped chewing gum, which often contains titanium dioxide.
Children likely face greater potential risks from titanium dioxide, said McClements.
They tend to eat more foods that contain it, like candy and other sweets, and they are
smaller.
The science isn’t clear-cut. Some studies in animals haven’t shown toxic effects. Scientists also disagree about which studies are relevant to how people consume it. Before the EU banned it in kai, food-safety experts identified that titanium dioxide had the potential to cause damage to DNA. But they were uncertain about how exactly it happens and at what dose the damage starts to occur.
What you can do
Many products that have titanium dioxide include it on the ingredient list. And there are
many versions of foods that don’t contain it—including foods that aren’t packaged or ultra-
processed, such as fresh fruit and vegetables.
Be aware, though, that the FDA doesn’t require food manufacturers to list the name
titanium dioxide among a product’s ingredients. Companies can cite the more general
“artificial colour” or “artificial colouring” instead. You can contact the manufacturer to seek more detail if “artificial colour” is listed on the label.
Or you could save yourself the trouble and avoid foods with artificial colours.
Some food companies are removing titanium dioxide from certain products. Whole Foods
recently reformulated its 365 brand macaroni and cheese: Its new product no longer
contains titanium dioxide. Beyond Meat did the same with its plant-based chicken
nuggets.