Sea vegetables have traditionally been consumed in moderate amounts and on a regular basis to provide a balanced intake of minerals. For example, kombu is a good source of iodine, which is necessary for proper thyroid function and is of general benefit to health, but a few people with sensitive thyroids may have an adverse reaction to excess iodine, and for this reason kombu should not be consumed in excess.
Over the last few decades, medical researchers have discovered that a diet rich in sea vegetables reduces the risk of some diseases and helps the body eliminate dangerous toxins.
Weight Control
If you're watching your weight, sea vegetables could be a useful addition to your diet. They are high in fibre, contain next to no calories and provide a good balance of essential minerals.
Digestive Health
Nutrients in sea vegetables appear to cleanse the colon and improve digestion and absorption. Scientists at the University of Newcastle-upon-Tyne have found that alginate, the sticky starch present in brown sea vegetables, can strengthen gut mucus, slow down digestion and make food release its energy more slowly (2).
In another study comparing the faecal flora resulting from the Japanese diet with the Western diet, significantly greater numbers of beneficial oxygen-loving (aerobic) organisms were found to derive from the Japanese diet (3). This is believed to be due to the antibiotic activity of sea vegetables, which destroys harmful anaerobic bacteria.
Binding Properties
Sea vegetables are known to bind heavy metals and radioactive pollutants that are present in the environment from industry and transport and remove them from the body. Scientists at McGill Univeristy in Canada showed that sodium alginate removes the radioactive element strontium, along with heavy metals such as cadmium and lead from the system (4).
Health Protection
Several decades ago, dietary researcher Dr. Weston Price found that natives of the high Andes carried a small bag attached to their necks containing a greenish-brown substance, a quantity of which was consumed every day. This substance was sea vegetable obtained with much difficulty from coastal Indians, but which these healthy dwellers of the high Andes would not do without (5).
Dr Jane Teas of Harvard University has published a paper proposing that kelp (kombu and wakame) consumption might be a factor in the lower rates of breast cancer in Japan (6). She is now researching the effects of sea vegetables as a natural alternative to HRT. Sea vegetables are very high in lignans, plant substances that become phytoestrogens in the body, meaning that they help to block the chemical oestrogens that can predispose people to cancers such as breast cancer.