Kelp's therapeutic uses
Kelp, a type of large brown seaweed, is recognized for its potential therapeutic uses, particularly as a nutrient-rich food supplement. It is a staple in the diets of various cultures, especially in regions like Japan and Hawaii, and is often included in vitamin and mineral supplements due to its high content of iodine, folic acid, and other essential nutrients. While kelp is primarily consumed for its nutritional benefits, some studies suggest it may have additional therapeutic properties, such as supporting cardiovascular health, aiding in diabetes management, and possibly preventing certain types of cancer.
Research has indicated that components in kelp could help in preventing infections from viruses like influenza and herpes, although further rigorous studies are required to validate these claims. Kelp is also marketed for weight loss, but evidence supporting its effectiveness is limited. While it can be beneficial for those with iodine deficiencies, excessive intake poses risks, including thyroid dysfunction and potential arsenic toxicity from contaminated supplements. As such, individuals should approach kelp supplementation with caution, especially if they have existing thyroid conditions or are considering high doses.
Kelp's therapeutic uses
DEFINITION: Natural plant product used to treat specific health conditions.
PRINCIPAL PROPOSED USE: Nutrition
OTHER PROPOSED USES: Cancer prevention, colds and influenza, herpes, high blood pressure, human immunodeficiency virus infection support, weight loss, thyroid health, cardiovascular health, diabetes management, antioxidant, anti-inflammatory
Overview
Kelp refers to several species of large, brown algae that can grow to enormous sizes far out in the ocean's depths. Kelp is a type of seaweed, but not all seaweed is kelp. The term “seaweed” loosely describes any type of vegetation growing in the ocean, including many other algae and plants.
Kelp is a regular part of a normal human diet in many parts of the world, such as Japan, Alaska, and Hawaii. Because of its nutrient value, it is also incorporated into some vitamin and mineral supplements. Kelp is a good source of folic acid (a B vitamin), as well as many other vitamins and minerals–especially iodine—but iodine is also a potential source of side effects.
Requirements and Sources
Supplements containing kelp can be purchased at most pharmacies and health food stores. Kelp used in food preparation is available at groceries that stock specialties for Asian cooking.
Therapeutic Dosages
There is no appropriate therapeutic dosage of kelp, as it is not known whether kelp is truly therapeutic for any conditions. However, because of its high iodine content, it is important not to overdo the use of kelp. The iodine content in seventeen kelp supplements studied by one group of researchers varied from 45 to 57,000 micrograms (mcg) per tablet or capsule. The recommended daily intake for iodine is 150 mcg per day for people over four, and taking a great deal more than this can cause thyroid problems.
Therapeutic Uses
Kelp is used primarily as a nutrient-rich food supplement. The results of highly preliminary test-tube and animal studies have suggested other potential uses for kelp. For example, there is some evidence that elements in kelp might help to prevent infection with several kinds of viruses, including influenza, herpes simplex, and human immunodeficiency virus (HIV). However, far more research, including more double-blind, placebo-controlled studies, would be necessary to know whether kelp is actually helpful for any of these health problems.
Additionally, kelp has been marketed as a weight-loss product, but few meaningful scientific studies indicate that it is effective for this purpose. One study conducted in Japan did find participants who supplemented their diets with kelp powder had a decrease in body fat percentage. Another common claim regarding kelp is that, because of its high iodine content, it can help all kinds of thyroid problems. This claim, however, is misleading and even dangerous. Kelp is probably good for people who are deficient in iodine, but iodine deficiency is rare, and taking extra iodine when it is not needed can cause dysfunction of the thyroid.
There are several other proposed therapeutic uses for kelp. Some studies suggest that kelp may be a cancer preventative, especially for breast and colon cancers. Compounds found in kelp appeared to inhibit the growth of cancer cells in laboratory studies. Kelp may help decrease cholesterol and blood pressure, giving it cardiovascular benefits. It is also high in fiber. Kelp may also help regulate blood sugar, suggesting it could play a beneficial role in diabetes management. Kelp is also being investigated for its role in gut and bone health.
Safety Issues
Taking excessive kelp can overload the body with iodine and cause either hypothyroidism or hyperthyroidism, conditions in which the thyroid gland produces either too little or too much thyroid hormone. This potentially dangerous side effect is cause for caution. Individuals whose thyroid gland is already functioning incorrectly should avoid high doses of kelp except on a physician’s advice.
Additionally, published reports describe two cases of acne caused or worsened by taking large doses of kelp. This effect is also believed to be due to the large amounts of iodine in the supplement.
Finally, some kelp supplements have been found to contain levels of arsenic high enough to be toxic. Seawater contains highly diluted arsenic, but kelp, like other ocean life, can concentrate arsenic in its tissues. Two people with symptoms of arsenic poisoning who had been consuming kelp have been reported.
Bibliography
Aoe, Seiichiro, et al. "Effects of Daily Kelp (Laminaria japonica) Intake on Body Composition, Serum Lipid Levels, and Thyroid Hormone Levels in Healthy Japanese Adults: A Randomized, Double-Blind Study." Marine Drugs, vol. 19, no. 7, Jun. 2021, p. 352, doi:10.3390/md19070352. Accessed 18 Sept. 2024.
Arnarson, Atli, and Natalie Olsen. "Kelp Benefits: Boost Your Health with Seaweed." Healthline, 30 Mar. 2020, www.healthline.com/health/food-nutrition/benefits-of-kelp#disease-prevention. Accessed 18 September 2024.
Clark, C. D., et al. "Effects of Kelp Supplementation on Thyroid Function in Euthyroid Subjects." Endocrine Practice, vol. 9, 2003, pp. 363-369.
"Kelp." University of Rochester Medical Center, www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Kelp. Accessed 18 September 2024.