It’s not something most of us in the west grew up with, but sea vegetables – or ‘seaweed’ – is something we should all consider incorporating into our diets. It enhances our diet from a culinary as well as a health perspective. In Japan, sea vegetables have been eaten for thousands of years, but even here in the UK – where we are surrounded by water after all – seaweed is part of a traditional dish: Welsh laverbread.
Sea vegetables contain virtually all the minerals found in the ocean, and there are no other plants that carry more nutrients, trace minerals and minerals. As a group, sea vegetables are known for their ability to detoxify environmental toxins and heavy metals, such as cadmium, from the body. Not only are sea vegetables rich sources of iodine – a mineral required for proper thyroid function – but also calcium, magnesium, potassium and iron. They also supply some B vitamins, such as folic acid, riboflavin (B2) and pantothenic acid (B5). Moreover, they contain lignans – a chemical compound from plants – that is thought to provide protection from cancer and helps alleviate menopausal symptoms – as well as fucans, which can help reduce inflammation. Lignans (another great source are flaxseeds) block the hormonal signalling of oestrogen-related cancers. In addition, seaweed appears to impair angiogenesis, the growth of blood vessels for the nutrient supply to tumours. Fucoids, another component of sea vegetables, a polysaccharide (carbohydrate) that is particularly rich in kombu and wakame, is believed to be cancer-protective, too, but is easily destroyed even by light cooking. To benefit from it, kombu or wakame need to be consumed in their raw or dried form.
The sea vegetables most commonly used for food are from the family of brown seaweeds (arame, hijiki, kelp, kombu, wakame) and red seaweeds (nori, dulse).
This wiry Japanese sea vegetable has a sweet and mild flavour. It contains 100 – 500 times more iodine than shellfish and is a great source of iron and vitamin A. Arame has ten times more calcium than milk.
Another Japanese sea vegetable, which is the highest in calcium, but also a good source of iron (eight times more than beef) and vitamin A. It has a stronger flavour than arame. Both hijiki and arame are available dried (long strands, similar to pasta) and will expand when rehydrated.
Kelp – like arame is a rich source of iodine and has four times more iron than beef. It is often sold as a powder or flakes.
Kombu is sold dried in wide strips or sheets. Adding a strip of kombu to dried beans and lentils during cooking helps them cook faster and alleviates digestive problems (flatulence, bloating) some people suffer when eating pulses. It contains potassium, calcium, iodine and vitamins A and C.
Nori is probably the best known sea vegetable as it is used to wrap sushi. It is usually sold in shiny, black sheets that are made in a similar way to paper, from nori pulp, but is also available as flakes. Nori is rich in calcium, iron, potassium and vitamin A.
Dulse has a reddish brown colour and a chewy texture. It is available in pieces (dried) or as flakes. Although all of the above contain protein, dulse and nori are particularly rich sources of it, with 20 – 30 per cent of their dry weight consisting of protein.
Most health food shops sell dried seaweed, either as long, dried strands, sea vegetable salad (dried pieces) or flakes. It is also available as a condiment, mixed with sea salt. Some supermarkets sell seaweed, too, but mainly nori for sushi making. It is also a component in some healthy snack foods such as crackers or savoury biscuits. Note that ‘crispy seaweed’ in Chinese restaurants or the ready meals aisle in the supermarket is not usually made from seaweed, but cabbage. Delicious as it may be, it is also deep-fried and covered in sugar and salt, so it really has nothing in common with the sea vegetables discussed above.
For ideas on how to incorporate sea vegetables into your diet, read tomorrow’s Nutrilicious News. It is not too late to subscribe!