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Kelp Supplements

Kelp Supplements


Kelp, a variety of brown, edible seaweed of the family Laminariaceae. It is frequently used as a substitute for salt and is an excellent source of iodine, potassium, vitamin B-Complex vitamins, vitamin D, vitamin E, vitamin K, calcium and magnesium.

Method of Action


Several studies have shown kelp has good activity against many pathogenic microorganisms. It kills both gram positive and gram negative bacteria, including Staph and Strep, brucella, bacillus, Klebsiella, proteus, E. coli, salmonella, etc.

Most researchers believe the antibiotic property is due to brominated phenolic compounds (and not to the iodine). In one study, the diets of one of each of seven pairs of monozygotic (identical) twin cows was supplemented with kelp for seven years. During that period the cows with kelp-supplemented diets yielded more milk and had a much lower incidence of mastitis than did the controls. Since mastitis in cows is usually caused by unsanitary conditions, the antibiotic property of kelp wasprobably responsible for the difference.


Kelp has been conclusively shown to prevent breast cancer in women (especially Japanese women who use kelp as a part of the daily diet). Several mechanisms have been proposed to explain this effect:

1. First, kelp supplies a source of nondigestible fiber. This would increase fecal bulk. For example, alginate powder has been used successfully, without irritation or side effects to treat constipation in humans. The relationship between a high fiber/bulk diet and low colonic cancer rates is well known.

2. Kelp reduces cholesterol levels through inhibition of bile acid absorption and could therefore prevent cancers caused by faulty metabolism of bile acids.

3. By altering the nature of fecal flora, it may render harmless the colonic bacteria that could be carcinogenic.

4. Kelp may exert all anti-cancer effects through a direct cytotoxic effect. Secondary to this last property, kelp may mediate enhancement of the body's immune response system against potential carcinogens.

Hot water extracts of laminaria and sargassum varieties of kelp have proven effective in lab animals against Erhlich ascites carcinoma and transplanted Sarcoma 180 tumors. One study found 95% tumor inhibition, and six of nine animals had complete regression, using an extract of laminaria angustata.

The antitumor effect of many studies has only been detected in live animals, not in vitro. This has led researchers to theorize kelp works by enhancing a host-mediated immune response. But other workers have found, for example, a hot water extract of laminaria is effective in vitro against human KB cancer cell cultures, showing marked cytotoxic activity (more than 50% destruction of cancer cells). In further support of the immune system theory, mice immunized with grass pollen extract conjugated to sodium alginate had IgE antibody titers that were 16-fold lower than those of control mice. It was postulated alginate mediated its effects by stimulating T cells. In another study of antibody formation, mouse spleen cells incubated with sheep erythrocytes produced a doubling in antibody formation with 1.- mg/ml alginate was added.


Besides the hypotensive property, but in conjunction with it, several components of kelp, including laminine, have been shown to have good cardiotonic action.

Two cardiac principles were isolated from nekombu (the basal part of the blade of a laminariaceous seaweed). Fatty acids of C14, C16 and C19 were found to stimulate the isolated frog heart, while histamine dihydroiodate was found to accelerate the isolated guinea pig atrium. Histamine and iodine content of nekombu were 501 mg/kg and 3200 mg/kg respectively, indicating 36% of the total iodine present in nekombu is in the salt form of histamine.

In another test, extract from Undaria pinnatifida was found to increase contractile force in mouse whole atria, thereby showing good inotropic action. Another fraction of the same seaweed was found to increase contractile force in rat right and left atria; the fraction had no effect on the rate of spontaneously beating rat right atria, but had a positive inotropic action in the left atria. It was determined this fraction did not have a histamine-like action.


In Japan, 'kombu', a preparation of the blades of various kinds of Laminaria species, has been employed as a hypotensive agent form may years.

Research interest in the product picked up recently when one investigator found human hypertensive patients who drank 'kombu' experienced significant improvement in blood pressure readings, subjective well-being and cardiac efficiency, without any side effects. Other studies have obtained the same results, in humans and in rabbits, rats and other animals.

The active principles are believed to be histamine and laminine, though evidence exists other cardiotonic principles may be present in various species of kelp finding their way into the 'kombu' medication. Studies on independent species of Laminaria have also found lamanine to be hypotensive.

Inhibits radioactivity

Canadian researchers have found algin, an extract of brown kelp, though non-digestible, can prevent living tissue from absorbing radioactive materials, including strontium-90, barium, mercury, zinc, tin, cadmium, and manganese. These results have been replicated in other labs.

Strontium-90 is dangerous because it has a great affinity for calcium and will accumulate in food substances high in that mineral (e.g., milk and green leafy vegetables). Contaminated calcium will carry the pollutant directly to the bones where it damages the marrow. Kelp blocks this mechanism by preventing the strontium-90 from being absorbed in the body. It forms insoluble salts by stripping the metal ions from the calcium molecule. The salts are unabsorbable and are harmlessly excreted in the urine and feces.


Kelp is generally recognized as an excellent source of iodine. But kelp contains a good deal of additional nutritional value as well. It not only absorbs iodine from seawater, it also sponges up an enormous supply of essential nutrients, including protein, essential fatty acids, carbohydrates, fiber, trace elements, sodium and potassium salts, alginic acid, iron, copper, magnesium, calcium, potassium, barium, boron, chromium, lithium, nickel, silicon, silver, strontium, titanium, vanadium and zinc. These minerals not only maintain the health of the thyroid gland, but contribute to the overall health and resistance of the body as a whole.

Therapeutic Approaches

Kelp is an important general nutritive tonic world-wide. Until recent years it was, however, eaten almost exclusively and universally by the Japanese.

Studies have shown the Japanese intake of kelp is primarily responsible for their country's dramatically lower breast cancer rates, as well as the presence of less obesity, heart disease, respiratory disease, rheumatism and arthritis, high blood pressure, thyroid deficiency, infectious disease, and constipation and other gastrointestinal ailments.

The Japanese consume between 5 and 7.5 grams of kelp per capita per day. It is used in almost every meal, as garnish, vegetable, in soups, cakes, jellies, sauces, salads, and flour. The most common Japanese food is noodles made from kelp.

Among heavily westernized Japanese social-economic groups, kelp consumption is decreasing and all of the above diseases are increasing. Among the poor and the rural, kelp consumption is increasing and disease rates are decreasing.

Three of the major effects of kelp are nutritive, antibiotic and hypotensive. A preparation called 'kombu' which is the blades of various Laminaria species, has been employed as a hypotensive agent in Japan for many years. Recent studies have verified its efficacy. The active principles appear to be laminine and histamine.

Another important effect of kelp is its ability to increase the resistance to fevers and infections. That property is partially due to the herbs antibacterial action, partly to its nutritive value, and partly to unknown causes. Kelp has been found to offer good protection from many kinds of modern pollutants, carcinogens and toxins, including radioactive materials.

Brown kelp is the primary source of algin, a kind of fiber also having shown considerable anti-radioactive properties, and is also very hypocholesterolemic.

Kelp has cardiotonic action. It has been found to increase the contractile force in the atria, and to stimulate the hearts of frogs.

Kelp has been used for scores of years by Asian cultures to treat disorders of the genital-urinary tract, including kidney, bladder, prostate and uterine problems.

Clinical documentation shows kelp ingestion on a daily basis gradually reduces an enlarged prostate in older men to the point urination becomes painless.

Finally, since kelp is such rich source of iodine, it has effectively been used in the treatment of goiter and other thyroid-deficiency conditions. Among the Japanese, who may consume up to 25% of their diet in kelp, thyroid disease is practically unknown.

Toxicity Factors

Kelp has no known toxicity. The degraded carrageenan, derived from two red seaweeds (Irish Moss), has been implicated in causing colonic lesions in rats, but none of the brown seaweeds or their derivatives have been found to be carcinogenic. Even Irish Moss, if ingested in whole, i.e. non-degraded, form is perfectly safe, since it is non-absorbable.

Some kelp species are known for their relatively high arsenic content; however, extensive testing has found the arsenic, although certainly present, is in a biologically unavailable form.

Recently, four men were fed different kinds of seaweed in order to monitor the urinary excretion of arsenic. For kelp, 100% of the ingested arsenic was excreted in the urine within 60 hours, providing further evidence for the biological inertness of arsenic in seaweed. Thus brown seaweeds appear to be neither carcinogenic nor toxic.



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