Overview

Agar is a plant. People use it to make medicine. In Japan agar is called "kanten," and it is the main ingredient in "the kanten plan" or "the kanten diet."

People use agar for obesity, diabetes, constipation, yellowing of the skin in infants (neonatal jaundice), and other conditions, but there is no good scientific evidence to support these uses.

Agar contains a gel-like substance that bulks up in the gut. This stimulates the intestines and creates a bowel movement. This bulking effect is thought to make it useful as a laxative and for weight loss. Agar tends to make people feel full, so they might stop eating earlier than they otherwise would. Some people think this reaction will lead to weight loss. But so far, there is not enough reliable scientific evidence that supports this weight loss theory.

In dentistry, agar is used to make dental impressions.

In manufacturing processes, agar is used as an ingredient in emulsions, suspensions, gels, and certain suppositories.



How does it work ?

Agar contains a gel-like substance that bulks up in the gut. This stimulates the intestines and creates a bowel movement. This bulking effect is thought to make it useful as a laxative and for weight loss. Agar tends to make people feel full, so they might stop eating earlier than they otherwise would. Some people think this reaction will lead to weight loss. But so far, there is not enough reliable scientific evidence that supports this weight loss theory.

Uses & Effectiveness

Insufficient Evidence for

  • Diabetes. Early research shows that taking agar gel by mouth daily while following a traditional Japanese diet for 12 weeks doesn't improve pre-meal blood sugar levels or insulin resistance in obese people with type 2 diabetes and impaired glucose tolerance.
  • Yellowing of the skin in infants (neonatal jaundice). While research is mixed, most early research shows that giving agar by mouth for 5 days doesn't reduce bilirubin levels in infants with newborn jaundice. But when given by mouth along with light therapy, agar might increase the bilirubin-lowering effects of light therapy. It might also reduce the length of time that light therapy is needed.
  • Obesity. Early research shows that taking agar gel by mouth daily while following a traditional Japanese diet for 12 weeks reduces body weight by a small amount in obese people with type 2 diabetes and impaired glucose tolerance.
  • Constipation.
  • Other conditions.

More evidence is needed to rate the effectiveness of agar for these uses.

Side Effects

When taken by mouth: Agar is POSSIBLY SAFE for most adults when taken with at least one 8-ounce glass of water. If it is not taken with enough water, agar can swell and block the esophagus or bowel. Immediate medical attention is necessary if chest pain, vomiting, or difficulty swallowing or breathing occurs after taking agar.

Special Precautions and Warnings

When taken by mouth: Agar is POSSIBLY SAFE for most adults when taken with at least one 8-ounce glass of water. If it is not taken with enough water, agar can swell and block the esophagus or bowel. Immediate medical attention is necessary if chest pain, vomiting, or difficulty swallowing or breathing occurs after taking agar.

Children: Agar is POSSIBLY SAFE when given by mouth to infants with neonatal jaundice for up to 7 days.

Pregnancy and breast-feeding: There isn't enough reliable information to know if agar is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.

Bowel blockage (obstruction): Agar might make bowel obstruction worse, especially if it isn't taken with enough water or other liquid. Get medical advice before taking agar if you have a bowel obstruction.

Trouble swallowing: Agar might swell up and block the eating tube (esophagus) if it isn't taken with enough water or other liquid. This can be especially dangerous for someone who has trouble swallowing. Get medical advice before taking agar if you have a swallowing problem.

Interactions

    Minor Interaction

    Be watchful with this combination

  • Medications taken by mouth (Oral drugs) interacts with Agar

    Agar is a thick gel. Taking agar by mouth at the same time as medications might decrease how much medication your body absorbs. This could decrease the effectiveness of your medication. To prevent this possible interaction, take agar at least one hour after taking medications by mouth.

Dosing

The appropriate dose of agar depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for agar. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.
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