Kelp - Seaweed Superfoods
Kelp is a type of seaweed, widely distributed throughout the world’s oceans. Technically it belongs to a class of organisms called protoctists, sharing some similarities with plants. Brown/green in colour it grows rapidly in deep water and reaches considerable lengths, sometimes in excess of ninety metres. The rapid growth rate of kelp means that it is readily harvested and is a widely used ingredient in the Far East, with health supplements being commonly available in the West.
The popularity of kelp as a health supplement is due to several unique properties and the presence of several beneficial compounds and mineral ions:
Kelp is particularly rich in antioxidants. These are a diverse range of compounds that react with harmful chemicals called free radicals, released as by-products of cellular metabolism. Free radicals are highly reactive compounds that can cause damage to other molecules in cells, most notably DNA. Alterations to DNA can lead to cells dividing uncontrollably, resulting in the development of cancerous tumours; antioxidants therefore provide an important preventative measure against cancer. This is substantiated by the low incidence of certain types of cancer (e.g. breast and ovarian) in the Far East, contrasting with a much higher incidence in the West, where kelp is not commonly eaten.
Iron is essential in our diet as it provides the key element needed for the production of haemoglobin, the oxygen carrying molecule found inside red blood cells. Deficiency of iron leads to the condition of anaemia, characterised by an abnormally low number of red blood cells resulting in lethargy, fatigue and tiredness. Kelp and other seaweed species contain copious amounts of iron, preventing such dietary deficiency.
Iodine is essential for the production of two key hormones produced by the thyroid gland: triiodothyronine and thyroxine. Both hormones have a central role in regulating metabolic rate of body cells, as well as regulating protein synthesis, bone growth and sensitivity of cells to other hormones. A deficiency of iodine in the diet results in a condition called hypothyroidism, where the thyroid gland is unable to produce sufficient thyroxine and thyronine.
The consequence of this is a drastic decline in metabolism, with sufferers reporting a range of symptoms including weight gain, intolerance to cold, fatigue, poor muscle tone and depression. Severe deficiency may result in a condition called goitre, where the thyroid gland swells to several times the normal size and protrudes at the neck.
Kelp is well documented in preventing hypothyroidism, and again the incidence of such deficiency is extremely low in areas of the world where kelp is a staple of the diet. Interestingly kelp also provides some degree of protection from radiation, helping to prevent radioactive isotopes of iodine being taken up by the body and used in the production of thyroid hormones. This knowledge was used to great effect during the Japanese Fukushima disaster in 2011, with a dramatic increase in sales of kelp tablets from health food stores in the US.