Does red dye 40 cause hyperactivity in kids? Here’s everything we know

One synthetic food dye used to color or enhance color in processed foods has often been scrutinized for its link to hyperactive behavior in children.
One synthetic food dye used to color or enhance color in processed foods has often been scrutinized for its link to hyperactive behavior in children. | Adobe Stock

Red dye 40, a synthetic food dye used to color or enhance color in processed foods, has often been in hot water for its link to hyperactive behavior in children. Research shows some children experience a sensitivity to certain food dyes such as red dye 40 and may show side effects such as fidgeting and mood swings. Though there is a link between red dye 40 and hyperactivity, it is important to note red dye 40 does not cause ADHD.

Here is a guide to understanding red dye 40, what foods contain it, potential impacts of a red dye 40 sensitivity and how to determine if your child suffers from a food dye sensitivity.

What is red dye 40?

Red dye 40 is a synthetic food dye commonly used in candy, dairy foods and drinks to add or enhance color. Like most synthetic food dyes, red dye 40 is made from petroleum, reports Healthline.

The Food and Drug Administration approves of red dye 40 in foods. It is one of nine food dyes approved by the FDA. The FDA regulates any maximum amounts of food dye allowed in food and requires manufacturers to identify use on the ingredients label. Approved color additives must undergo inspection from the FDA with every new batch, to confirm the dyes contain what they are legally expected to.

Red dye 40 is created using two different types of sulphonic acids, the acids chemically react with each other and the dye is formed, per WebMD.

What is red dye 40 used for?

Red dye 40 is used in foods to artificially color food. It adds no nutritional value or flavor. It is important to note, some foods containing red dye 40 are not actually red in color, but will typically have a vibrant hue and stain your mouth, per Medical News Today.

Some of the most common foods containing red dye 40 include:

  • Soda.

  • Energy drinks.

  • Sports drinks (such as Gatorade).

  • Breakfast cereals.

  • Yogurt.

  • Flavored milk.

  • Ice cream.

  • Jello.

  • Pudding.

  • Protein powders.

  • Powdered drink mix.

  • Candy.

  • Gummies or fruit snacks.

  • Popsicles.

  • Chips.

  • Pastries.

Red food dye is also used in cosmetics and pharmaceuticals. Cough syrups, for example, often contain food dye. Manufacturers are required to list food dyes on all products which contain them. Check the label on the back to determine if red dye 40 is present, per Healthline.

Red dye 40 will be listed on the ingredients label. It may be identified as the following, per Medical News Today:

  • Red 40.

  • Red 40 Lake.

  • FD&C Red No. 40.

  • FD&C Red No. 40 Aluminum Lake.

  • Allura Red AC.

  • CI Food Red 17.

  • INS No. 129.

  • E129.

Does red dye 40 cause hyperactivity or ADHD in kids?

Several outdated studies claim that red dye 40 can cause ADHD, or attention-deficit/hyperactivity disorder, in kids. This is not true. Newer studies debunk these claims and suggest that while red dye 40 cannot cause ADHD, it can exacerbate symptoms of hyperactivity in kids with or without ADHD.

Children who do not have ADHD may experience ADHD-like symptoms as a result to consuming red dye 40, according to 2015 study. Displaying signs of hyperactivity due to consumption of red food dye does not mean a child has ADHD.

Symptoms of hyperactivity may include: fidgeting, interrupting conversations, inability to sit still, unable to concentrate, excessive talking, difficulty waiting for a turn and restlessness, according to the National Institute of Mental Health.

According to a 2021 report from the state of California, some children demonstrate more sensitivity to food dyes whether or not they have an ADHD diagnosis.

“Our review of human studies suggests that synthetic food dyes are associated with adverse neurobehavioral effects, such as inattentiveness, hyperactivity and restlessness in sensitive children,” the 2021 study claims.

“The evidence supports a relationship between food dye exposure and adverse behavioral outcomes in children, both with and without preexisting behavioral disorders.”

Why does red dye 40 cause behavioral changes?

Research is limited, but some experts believe red dye 40 and other synthetic dyes may cause behavior changes in kids due to a chemical change in the brain or a hypersensitivity causing an allergy-like reaction.

How to know of your child had a red dye 40 sensitivity or allergy

The best way to find out if your child suffers from a red dye 40 sensitivity or allergy is to cut foods with red dye out. Observe any changes or improvements in your child’s behavior.

“Try cutting out all foods with red dye 40 for a week or two,” Registered dietitian Julia Zumpano suggests to Cleveland Health Clinic. “Hopefully, you’ll notice an improvement in behavior. But you might not realize how the dye affects your kids until you begin to reintroduce foods and see their reactions.”

To screen for food intolerances, try following this guide from Cleveland Health Clinic.

What has the FDA said about red dye 40 studies?

The FDA still approves of red dye 40 in foods and suggests concerned parents speak with a physician about the potential effects of red dye 40. The FDA acknowledges there is evidence which suggests some children are sensitive to red food dye.

“The FDA has reviewed and will continue to examine the effects of color additives on children’s behavior. The totality of scientific evidence indicates that most children have no adverse effects when consuming foods containing color additives, but some evidence suggests that certain children may be sensitive to them,” reads a statement on the FDA website.

“The FDA will continue to evaluate emerging science to ensure the safety of color additives approved for use. Parents who wish to limit the amount of color additives in their children’s diet may check the food ingredient list on labels. Parents should also discuss any concerns with their family physician.”