Why would anyone want to eat seaweed also referred to as sea vegetables? People ask me this every time I bring up the subject. The answer is quite simple - Seaweed offers one of the broadest ranges of minerals of any food, containing virtually all the minerals found in the ocean and not surprisingly, many of the same minerals are found in human blood too.
The Health Benefits of Seaweed has a variety of unique phytonutrients including their sulphated polysaccharides (also called fucoidans). Unlike some other categories of vegetables, sea vegetables do not appear to depend on carotenoids and flavonoids for their antioxidant benefits, because in addition to these two important categories of antioxidants, vegetables from the sea contain several other types, including alkaloid antioxidants.
Sea vegetables are an excellent source of iodine, vitamin C, manganese, and vitamin B2. They are also a very good source of vitamin A (in the form of carotenoids) and copper as well as a good source of protein, pantothenic acid, potassium, iron, zinc, vitamin B6, niacin, phosphorus, and vitamin B1.
To truly understand many of the anti-inflammatory, anti-cancer, anticoagulant, antithrombotic, and antiviral properties of sea vegetables, you need to look no further than their sulphated polysaccharides. These unique compounds are starch-like molecules that are unusual in their complexity. Unlike many other types of polysaccharides, the fucoidans contain many chemical "branch points," and they also contain sulphur atoms. Multiple studies show anti-inflammatory benefits from consumption of the sulphated polysaccharides in sea vegetables.
Some of these benefits appear to take place through the blocking of selectins and from inhibition of an enzyme called phospholipase A2. Selectins are sugar-protein molecules (glycoproteins) that run through cell membranes. During inflammatory responses by the body, selectins are important in allowing inflammatory signals to be transmitted through the cell. By blocking the selectin function, some of the inflammatory signallings can be lessened. In the case of chronic, unwanted inflammation, this blocking of selectin-related signals can provide important health benefits.
Interest in this aspect of sea vegetable intake and anti-inflammatory benefits has received special focus in the area of osteoarthritis. More widely present in unwanted inflammatory problems is overactivity of the enzyme phospholipase A2 (PLA2). This enzyme is important for the creation of the omega-6 fatty acid called arachidonic acid (AA), and AA is itself the basic building block for a wide variety of pro-inflammatory messaging molecules.
Many corticosteroid medications lower inflammation by blocking PLA2, as does liquorice, turmeric, and the flavonoid quercetin. The association of sulphated polysaccharides with decreased PLA2 activity may be especially important in the anti-inflammatory benefits of sea vegetables.
Sea vegetables' sulphated polysaccharides are also associated with its anti-viral activity. Best studied in this area is the relationship between sulphated polysaccharides and herpes simplex virus 1 (HSV-1) and herpes simplex virus 2 (HSV-2). By blocking the binding sites used by HSV-1 and HSV-2 for cell attachment, sulphated polysaccharides help prevent replication of these viruses. It's important to point out that none of these HSV and sea vegetable studies has involved individuals with HSV who incorporated sea vegetables into their diet.
Instead, the studies have been conducted in the lab using human fibroblast cells inoculated with HSV. We don't yet know whether dietary sea vegetables will help prevent HSV replication in individuals with HSV, even though we greatly look forward to future research results obtained in clinical studies with individuals who have HSV and add sea vegetables to their diet.
Many of the cardiovascular benefits of sea vegetables can also be attributed to their sulphated polysaccharide content. Extracts from sea vegetables are sometimes referred to as "heparin-like extracts" because they exhibit some of the same properties as this widely used anticoagulant medication. Heparin itself can be described as a sulphated polysaccharide, and like the sulphated polysaccharides found in sea vegetables, it can decrease the tendency of blood platelet cells to coagulate and form clots. (A blood clot can also be called a "thrombus"—thus giving rise to the term "antithrombotic" in the description of sulphated polysaccharides.) In addition to their anticoagulant and antithrombotic benefits, however, sea vegetables have also been shown to help lower total cholesterol and LDL cholesterol and to improve cardiovascular health in this way.
Not fully understood but of increasing interest to researchers are the anti-cancer benefits of sea vegetables. Research interest in this area has tended to focus on colon cancer, with a special emphasis on the loss of calcium-sensing receptors (CaSRs) in colon cancer cells, and the ability of sea vegetable extracts to alter CaSR-related events. But since chronic, unwanted inflammation and chronic oxidative stress are both risk factors for the development of cancer, it would be quite natural for scientists to be interested in sea vegetables are anti-cancer foods not only in the case of colon cancer but for other types of cancer as well.
Sea vegetables are well-researched as containing a variety of anti-inflammatory and antioxidant compounds, and this nutrient combination is likely to result in some risk-lowering benefits in the case of colon cancer and other cancer types. Although much more research is needed in this area, we expect the anti-caner benefits of sea vegetables to become more firmly established over time.
Of special note in this area of cancer and sea vegetables is the issue of estrogen-related cancers, especially breast cancer. Intake of sea vegetables appears able to modify various aspects of a woman's normal menstrual cycle in such a way that over long periods (tens of years) the total cumulative oestrogen secretion that occurs during the follicular phase of the cycle gets reduced.
Since overproduction of oestrogen can play a role in the risk of breast cancer for women who are estrogen-sensitive, sea vegetables may offer unique benefits in this regard. It's also important to note that cholesterol is required as a building block for the production of oestrogen, and intake of sea vegetables has repeatedly been shown to lower blood levels of total cholesterol and LDL-cholesterol.
Sea vegetables have been rightly singled out for their unique mineral content. You're going to find measurable amounts of calcium, copper, iodine, iron, magnesium, manganese, molybdenum, phosphorus, potassium, selenium, vanadium, and zinc in sea vegetables, and in some cases (like iodine) you can simply not find a more concentrated mineral source.
Brown algae like kombu/kelp, wakame, and arame can be particularly concentrated sources of iodine, and for some health conditions - like hypothyroidism, in which the cells of the thyroid make too little thyroid hormone - increased iodine intake can provide important health benefits. The wide variety of minerals found in sea vegetables is simply not found among most other vegetable groups.
The vanadium content of sea vegetables is an area of special interest concerning their mineral content. While research in this area remains inconclusive, sea vegetables may be able to help us increase our cells' sensitivity to insulin, help us prevent overproduction of glucose by our cells, and help us take existing blood sugars and convert them into storable starches. All of these factors would help us increase our blood sugar control, and lower our risk of type 2 diabetes.
Sea vegetables may turn out to be a better source of bioavailable iron than previously thought. One tablespoon of dried sea vegetable is likely to contain between 1/2 milligramme and 35 milligrammes of iron. At the lower end of this range, the iron content of sea vegetables is not that significant. But at the higher end of this range, the amount of iron found in sea vegetables is outstanding. (As an overall iron rating in our food rating system, we describe sea vegetables as being a "good" source of iron.) The iron found in sea vegetables is also accompanied by a measurable amount vitamin C. Since vitamin C acts to increase the bioavailability of plant iron, this combination in sea vegetables may offer a special benefit.
The antioxidant content of sea vegetables also deserves mention concerning its health benefits. While sea vegetables do contain measurable amounts of polyphenols like carotenoids and flavonoids, they also contain other phytonutrient antioxidants, including several types of alkaloids that have been shown to possess antioxidant properties. Coupled with measurable amounts of antioxidant vitamins (like vitamins C and E) and antioxidant minerals (like manganese and zinc), sea vegetables can be expected to help us reduce our risk of unwanted oxidative stress and many types of cardiovascular problems that are associated with poor antioxidant intake.
Please take note that the information on this site is designed for educational purposes and is intended solely for a general readership. The contents herein are not intended to offer any personal medical advice or to diagnose any health issues you may have. This information is also by no means a substitute for medical care by a licensed healthcare provider. For that, you'd need to consult your medical doctor or a health care practitioner for any advice should you require prescription medication.