When choosing which seaweed to buy, it helps to think of seaweeds as vegetables from a different realm, the sea. Like our land vegetables, seaweeds present a wide range of sensory experiences: colours, textures & flavours will vary from one to the next. Within a group, a family even, the variation is surprising in both culinary applications and nutritional benefits.
Because Seaweeds are photosynthetic, their colour and location in the water depend upon the sun. The familiar green seaweeds, highest in chlorophyll, thrive where the water is clear or shallow. The brown seaweeds grow in the subtidal areas, about 1-2 meters below the surface where red and orange wavelengths are absorbed. Red seaweeds mostly found much deeper - 100 meters - because blue & violet wavelengths are able to penetrate greater depth. So seaweeds are classified in 3 groups according to their pigment and their chemistry and although each seaweed has its unique profile, active ingredients and benefits, seaweed from the same group share some common traits:
- Brown seaweeds: known for their richness in iodine, include the largest sea plants, some of them part of large under-water forests. (There are about 160 species in New Zealand). Although grouped as ‘brown’, their colour may vary between orange, gold, khaki, dark green, brown and black brown.
In addition to their iodine content, they also contain other unique substances that are being researched for their beneficial impact on degenerative diseases: alginates (detox radiations & heavy metals), fucoidan (cancer & infections), laminarin (cardio-vascular health) & lignans (oestrogen related illnesses). Brown seaweeds naturally contain a high concentration of minerals & trace elements, especially calcium, magnesium, potassium & zinc. They also contain Omega 3 & 6 fatty acids in a favourable ratio (1/2).
Their main health benefits are: nourish thyroid gland & brain, balance hormones, improve metabolism & facilitate weight loss, detox environmental toxins from the body, inhibit cancer cell growth and facilitate bone & joint health.
- Red seaweeds: the oldest & largest group of algae with over 6000 species worldwide (roughly 570 species of found along the NZ coast). Their distinctive colour pigments allow them to survive at great depths. They vary greatly in size, shape and ecosystem, and despite their name, their colour ranges from pink through to crimson, purple and orange.
Red seaweeds are an excellent source of minerals, carbohydrates, antioxidants, enzymes and generally very high in dietary fibre. They are also rich in agar and carrageenan and have a positive potassium/sodium balance. Red seaweeds are an excellent vegetarian source of high quality, complete protein - containing all the essential amino acids the diet requires. They are also a source of heme iron (a form of iron that can actually prevent iron-deficiency anaemia). Red seaweeds are a good source of iodine, well suited to maintaining healthy thyroid function.
They have a tonic effect on the body - strengthening the immune system and facilitating re-mineralisation, promote cardiovascular health & regulate cholesterol, nourish the nervous system - improving resistance to stress, relieve congestion in colds & flu, reduce inflammation and are naturally anti-viral, anti-bacterial, anti-parasitic, anti-biotic, anti-septic and anti-fungal, and soothe the skin and the digestive tract.
- Green seaweeds: grow closest to the shore and are closely related to land plants. Often noticed because of their vibrant colours - various greens & yellows, they are fewer in number than the red or brown seaweeds (about 140 species in New Zealand).
Green seaweeds are the emeralds of the sea and they contain a wealth of minerals & trace elements, many times greater than is found in land-grown vegetables. They offer a large amount of digestible vegetable protein (up to 70%) and are an important source of calcium, iron, enzymes and anti-oxidants. They are a top source of chlorophyll, fibre and Vitamin A, B & C.
They are said to improve digestion and reduce sugar absorption, balance blood PH, antiviral against influenza, soothe burns, cuts & sores as a compress or poultice, toning, hydrate & nourish the skin, and clear intestinal worms.
Disclaimer: This material is provided for educational purposes only and IS NOT intended as a substitute for professional medical advice, diagnosis, or treatment. This information is generic and should be verified by a qualified health practitioner for specific & individual needs & requirements.