Overview

Carrageenan is a fiber that comes from seaweed. Small amounts of carrageenan are commonly added to foods, drinks, and formula to improve their texture. Carrageenan is also an ingredient in some nasal sprays. Large amounts of carrageenan powder are sometimes used to improve gut and digestive health, but the benefits are not well defined. These large amounts of carrageenan may cause bloating, gas, constipation, or diarrhea. Before using carrageenan, tell your health care provider about all of your health conditions and any medicines or supplements you may be using.

Uses

What is carrageenan used for?

Carrageenan is commonly added to foods and drinks to improve their texture.

Carrageenan powder is sometimes used to improve gut and digestive health. Nasal sprays containing carrageenan are sometimes used to prevent infections and allergies. However, the benefits of carrageenan for these uses are not well defined.

Note: Carrageenan is generally recognized as safe (GRAS) by the FDA. Learn more about GRAS status here.

How does carrageenan work (mechanism of action)?

Carrageenan is a type of fiber that comes from sea moss (Chondrus crispus), a form of red seaweed that grows on rocks in the Atlantic ocean. Carrageenan is often used to thicken foods or give them a more gel-like texture. It may be added to dairy, meats, beverages, infant formula, pet food, and other products. Carrageenan comes in three main forms: iota-, kappa-, and lambda-carrageenan. Each of these forms has a structure similar to the others, but it is not clear if they may have different effects in the body.

Carrageenan is a form of soluble fiber, which may help keep your bowel movements more regular. It may also help increase the growth of healthy bacteria in your gut and slow down the growth of bad bacteria. Some people add large amounts of carrageenan powder to foods or drinks to improve gut and digestive health. But the benefits of taking carrageenan for any purpose are not well defined.

Carrageenan is used as an ingredient in some nasal sprays that are marketed for preventing respiratory infections and allergies. In these products, carrageenan is thought to coat the inside of the nose, blocking viruses, pollen, and other substances from entering. But it is not clear if carrageenan can truly protect the nose from these substances or how long carrageenan stays in the nose after using the spray. Many of these products also contain other ingredients that may have different effects and side effects. The benefits of using carrageenan nasal sprays for any purpose are not well defined.

How should I store carrageenan?

You should store carrageenan according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.

Side Effects

What are the most common side effects of carrageenan?

When carrageenan is added to foods in small amounts, it seems to be well tolerated. The most common side effects of large doses of carrageenan are listed below. These side effects may vary depending on the specific product you are using. Tell your health care provider if you have any of these side effects that bother you.

• Bloating or gas
• Constipation or diarrhea

There may be other side effects of carrageenan that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of carrageenan?

While less common, the most serious side effects of carrageenan are described below, along with what to do if they happen.

Severe Allergic Reactions. Carrageenan may cause allergic reactions, which can be serious. Stop using carrageenan and get help right away if you have any of the following symptoms of a serious allergic reaction.

• Breathing problems or wheezing
• Racing heart
• Fever or general ill feeling
• Swollen lymph nodes
• Swelling of the face, lips, mouth, tongue, or throat
• Trouble swallowing or throat tightness
• Itching or skin rash
• Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
• Nausea or vomiting
• Dizziness, feeling lightheaded, or fainting
• Stomach cramps
• Joint pain

Precautions

Who should not use carrageenan?

Allergies to Ingredients. People who are allergic to any of the following should not use carrageenan.

• Carrageenan
• Any of the ingredients in the specific product

Your pharmacist can tell you all of the ingredients in the specific carrageenan products they stock.

What should I know about carrageenan before using it?

Carrageenan is generally recognized as safe by the FDA. It can be added to foods, drinks, formula, and other products, but it cannot be marketed to treat or cure a disease.

Read and follow the directions on the specific product you are using, or use it as recommended by your health care provider.

Keep carrageenan out of the reach of children.

If you are using carrageenan powder, use an appropriate measuring device to measure the powder, such as the device included with the product. Read the label carefully and measure the amount stated on the label.

When carrageenan is treated with a strong acid in a lab, it breaks down into very small pieces. These small pieces are known as poligeenan. There is some concern that poligeenan may be unsafe when taken by mouth. However, the acid in your stomach is weaker than the strong acid used in a lab, so your body is not able to turn carrageenan into these very small pieces. Food safety authorities in the U.S. and Europe consider food-grade carrageenan to be safe to take by mouth.

What should I tell my health care provider before using carrageenan?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if carrageenan is right for you.

In particular, make sure that you discuss any of the following.

Other Medicines and Supplements.Carrageenan may interact with other medicines and supplements. Before using carrageenan, tell your health care provider about any prescription or OTC medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how carrageenan could affect pregnancy or harm a fetus. Tell your health care provider if you are pregnant or plan to become pregnant.

Breastfeeding. It is not known if carrageenan passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does carrageenan interact with foods or drinks?

There are no known interactions between carrageenan and foods or drinks.

It is unknown if drinking alcohol will affect carrageenan.

Does carrageenan interact with medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

Small amounts of carrageenan, which are found in many foods and drinks, are not expected to interact with any medicines. However, adding large amounts of carrageenan powder to foods or drinks may affect the absorption of some medicines.

The interactions between carrageenan and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with carrageenan is incomplete. Always check with your health care provider before using carrageenan with any medicines.

Dosing

What should I do if I accidentally use too much carrageenan?

If you or someone else has used too much carrageenan, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

Carrageenan is an ingredient found in many foods and drinks. It is also included in some nasal sprays. Read all product labels closely, and speak with a health care provider about how to use carrageenan safely. If you are adding carrageenan to your foods and drinks, do not use more than the amount recommended on the product label.