Asian people and those who live in coastal communities throughout the world have been eating seaweed for thousands of years, and many of these populations are known for their excellent rates of longevity. Seaweed is a food high in vitamins, minerals, antioxidants and (somewhat surprisingly) protein. And thanks to its inhibition of the digestive enzyme lipase, which breaks down fat so it can be absorbed by the body, it’s good for reducing your waistline as well!
Seaweed’s Use in Functional Foods
Researchers at the Irish Agriculture and Food Development Authority, Teagasc, a governmental agency that provides research services and advice to the nation’s agriculture and food industries, have been looking to seaweed as a rich source of healthy nutrients to add to the development of functional foods.
Functional foods are foods to which supplementary ingredients have been added to give them additional benefits such as improving health and preventing or treating particular diseases. Seaweed is already used in a wide range of food products, including pizza, sausages, frozen meat products, soups and salads, to provide added flavor and nutrition.
Teagasc is currently examining the effect of one type of seaweed, Palmaria palmata (dulse), on bread products. They found that dulse possesses a natural bioactive peptide that acts as an ACE-I inhibitor, which may be useful in helping to fight cardiovascular disease by lowering high blood pressure. These peptides may also be found in meat, dairy, eggs and fish, but reducing meat intake is often advised for those with high blood pressure, so finding an alternative food source is appealing.
A Healthy Protein Alternative
Of particular use to vegetarians and vegans, seaweed can be an inexpensive source of high protein that may be a good alternative to the current choice for inexpensive vegetable protein, soybeans. Soybeans have a drawback in that they also contain phytoestrogens that mimic human hormones. This has been the cause for some concern, as they may cause disrutions to normal hormone functioning, particularly in relation to sex hormones. Eating too much soy may affect fertility, lactation and the normal sexual development of children at puberty. Seaweed has not been shown to exhibit these effects.
Seaweed’s Nutritional Benefits
Seaweed is incredibly high in a number of important vitamins and minerals, and each variety of seaweed has its own special health benefits. Some of the most commonly eaten seaweeds are Nori (Porphyra species), Kombu (Laminaria japonica), Arame (Eisenia bicyclis) and Wakame (Undaria pinnatifida).
Nori is the seaweed with one of the richest sources of protein, comprising up to 50% of its weight. One sheet of nori has as much omega-3 fatty acid as a cup of avocado, and is high in fiber. It also contains taurine (important for healthy cholesterol levels), vitamin C and vitamin B12 (which is hard to find in non-meat based foods).
Kombu is an excellent source of iodine, which is necessary for a healthy thyroid and metabolism. A study published in the journal Phytotherapy Research found that kombu reduces clotting. Researchers are investigating ways in which this may be of use to those who suffer from clotting problems. Kombu also reduces improves cholesterol profiles: it reduces triglycerides, lowers levels of "bad" LDL cholesterol and raises levels of "good" HDL cholesterol.
Arame has antiviral properties and is high in magnesium, a mineral useful for reducing muscle cramping, and is as essential as calcium (which it also contains) for the maintenance of strong bones. It is also high in iron, vitamin A and iodine.
Wakame can practically be considered a superfood. Not only is it low in calories (about 5 calories per serving) for the nutrition it provides, it also can help to reduce your risk of diabetes, heart disease, cancer and obesity. It promotes a healthy immune system and reduces inflammation. It contains vitamins A, C, D, E and K, in addition to folate and riboflavin. Its lignans are particularly useful in preventing certain types of cancer, such as breast cancer. Fucoxanthin, the chemical that gives wakame its color, can help in weight reduction by increasing the rate at which fat is broken down by the body, according to a Japanese study.