Food dyes are generally safe to eat, but some people may be sensitive to them and develop intolerance or allergic reactions. Learn how to spot the signs and get tested if you react to them.

Have you ever noticed that you don’t feel well after eating certain foods? Certain diets may contain a lot of ingredients that might not agree with everyone. These may include lactose, wheat, and soy, as well as additives like monosodium glutamate (MSG) and food dyes.

You might have an intolerance or allergy if you have a physical reaction after eating foods that contain these ingredients.

Food intolerance means your body doesn’t break down the food properly, or that you’re sensitive to it. A food allergy involves an immune system reaction that can be serious.

The Food and Drug Administration (FDA) makes sure that all food additives, including dyes, are safe to eat. Yet, some people are more sensitive to dyes than others. And even though food dye allergies are rare, they still can occur.

If you suspect you might be allergic to a particular dye, here’s how to spot the signs and avoid foods that contain it.

Food dye allergies are rare. Overall, experts believe that food dyes affect only a small number of people. Food additives can be naturally occurring or made in a laboratory.

Research has linked some dyes to allergic reactions, such as:


Carmine, also referred to as cochineal extract or natural red 4, comes from dried bugs. It has been used in food since the 16th century. It’s also found in cosmetics.

Research has noted a variety of reactions, including:

It’s also suspected to have a role in cases of anaphylactic shock where a cause isn’t easily identified.

You can find natural red 4 dye in:

  • burgers and sausages
  • drinks
  • candy
  • fruit yogurt

Red 40

Red 40, also known as Allura Red, is the most commonly used red dye in various products. The dye comes from petroleum distillates or coal tars. Foods that aren’t red can sometimes contain Red 40. However, the FDA mandates the dye be listed by name on food and product labels.

Red 40 can cause allergy-like reactions in some people, such as hives and facial swelling. The FDA has acknowledged problems with this food dye but maintains that the evidence of harm was not consistent or substantial.

You can find Red 40 in:

  • cereal
  • beverages
  • cosmetics
  • candy
  • fruit snacks

Yellow 5

Yellow 5, also referred to as tartrazine, is one of three yellow food dyes that has been associated with allergic reactions. People have reported hives and swelling after eating foods containing Yellow 5.

Studies many years ago also suggested tartrazine might trigger asthma attacks in children, although research from 2010 hasn’t found the same evidence.

You can find Yellow 5 in foods like:

  • candy
  • canned vegetables
  • cheese
  • drinks
  • ice cream
  • ketchup
  • salad dressings
  • hot dogs

Yellow 6

Also called Sunset Yellow, Yellow 6 is the third most widely used dye. Reports of human hypersensitivity to Yellow 6 date back to 1949. There have been cases linking the dye to instances of anaphylactic shock, stomach cramps, skin lesions, and hives.

Yellow 6 can be found in:

  • cereals
  • drugs
  • gelatin
  • candies
  • sausage
  • cosmetics
  • bakery goods


Another yellow dye, annatto, comes from the seeds of the achiote tree, which is found in tropical countries. Annatto gives foods a yellow-orange color. There are cases of mild skin reactions from annatto.

Some older studies have reported cases of severe, anaphylactic reactions in people who were sensitive to this dye.

Annatto is found in:

  • cereals
  • cheeses
  • drinks
  • snack foods

Blue 1

Blue 1, also called Brilliant Blue, is the more common of the two FDA-approved blue dyes and one of the oldest approved dyes in use. Some studies have linked the dye to potential neurotoxicity in fetuses and children. Neurotoxicity refers to damage to the nervous system.

Blue 1 is found in:

  • beverages
  • cereals
  • candies
  • drugs
  • cosmetics (excluding eye area)

The symptoms of a food dye reaction can be mild or severe. During a mild reaction, you might notice:

  • flushing
  • headaches
  • hives
  • itchy skin

A severe reaction may include:

  • swelling of the face or lips
  • tightness in the chest
  • difficulty breathing, or wheezing
  • dizziness or fainting
  • fast heartbeat
  • low blood pressure
  • tightness in your throat
  • trouble breathing

If you develop severe symptoms, call 911 immediately. This reaction can be life threatening.

If you know you have a severe food dye allergy, you should carry an epinephrine auto-injector at all times. An auto-injector is considered the first-line treatment of a severe food allergy reaction.

With most food allergies, your doctor may give you a blood test or skin prick test to find the source. Currently, no tests are available to diagnose a food dye allergy. You may have to pinpoint the allergen using some trial and error.

One option is to write down everything you eat in a food diary and note when you have a reaction. Then you can try avoiding those foods for a few weeks to see if your symptoms go away.

Another option is to do a food challenge. During a food challenge, your doctor will give you a series of foods. One or more of the foods will contain the dye you suspect is causing your problem, but you won’t know which one. If you have a reaction, you’ll know you’ve found the culprit.

The key to preventing an allergic reaction is to avoid any foods that contain the allergen. Total avoidance is easier said than done, though. Dyes can hide in foods where you’d never expect them. They can even lurk in some medications and supplements.

You may need to become a label detective, reading the ingredient list very carefully with every product you buy. If you’re not sure whether a certain food or medication contains the dye, call the manufacturer to ask, or simply avoid it or consider an alternative.