Kelp, known by the scientific name Fucus vesiculosus, is a type of brown seaweed that grows in colder ocean waters. Sometimes called kelpware, black-tang, bladderfucus, cutweed and bladderwrack, mineral-rich kelp is used by natural health practitioners to treat many diseases and disorders, including high blood pressure and cholesterol. Kelp is available in both dried bulk form and as a powder that can be used to make caplets.
While kelp is a fairly recent introduction to the American diet and lifestyle, according to the "Gale Encyclopedia of Alternative Medicine," the Japanese have been enjoying kelp for over 1,500 years. In Japan, kelp is used as a condiment, to make noodles, and in many other foods. It may be in part due to the amount of kelp consumed in Japan that the Japanese have a relatively low rate of breast cancer, heart disease, high blood pressure and thyroid disease.
The kelp you find in health food stores comes from a different species of kelp than is eaten in Japan, but many holistic health practitioners believe it offers similar benefits. Commercial kelp is grown in kelp farms, where it is harvested in a way that preserves its many nutrients.
While kelp's most popular medicinal use is to help with thyroid function, some people also use kelp to help with blood pressure and cholesterol levels. They believe kelp can help lower cholesterol by inhibiting your body's absorption of bile acids that contain cholesterol-raising compounds. Unfortunately, there is not sufficient empirical evidence to demonstrate that kelp is indeed successful at managing cholesterol or blood pressure.
Because iodine is important in thyroid function, people who have low levels of iodine may benefit from supplementing with kelp, as it is iodine-rich. Kelp is used by some people to treat hypothyroidism, goiters and metabolic disorders. Again, there is not yet any scientific evidence to back up this use of kelp. Talk with your physician before beginning any new herbal or medication regimen.
Some people also use kelp for aching joints or rheumatoid arthritis, constipation and to rid the body of toxins.
The daily dosage of kelp that herbalists recommend you take is approximately 10 to 15 milligrams. You can opt for kelp in powder, caplet or tincture form, or you can even make kelp tea. To make kelp tea, pour about a cup of boiling water over about 2 to 3 teaspoons of dried powdered kelp, then allow the tea to steep for about 10 minutes. You can drink kelp tea up to three times per day.
While it may be easy to dismiss kelp as natural and therefore safe, the National Institutes of Health suggests that this would be a mistake. According to NIH's MedlinePlus website, you should use caution when taking kelp. Because of its high levels of iodine, kelp can be unsafe for people in several situations. If you have thyroid problems, you should be careful taking kelp. Women who are pregnant or nursing should not take kelp, as it is "likely unsafe" to do so. Kelp may affect fertility and make it more difficult for you to become pregnant. You should not take kelp two weeks before any surgery because it can make your blood clot more slowly than usual. Discuss taking kelp with your physician before you begin. Avoid eating kelp that you find in the ocean, as it can absorb toxins found in the water. Only kelp that has been grown for consumption should be used.
- "Gale Encyclopedia of Alternative Medicine"; Kelp, Jennifer Wurges and Rebecca Frey, Ph.D.; 2005
- "The Natural Pharmacy"; D.C. Lininger; 1998
- MedlinePlus: Bladderwrack