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功效
1. Dietary Fibers
Modern diets today, especially in the U.S. are high in refined
and processed foods and are often lacking in the necessary dietary
fiber. Dietary fiber is necessary for clearing the digestive system.
Constipation elevates blood pressure, however the abundant dietary
fiber of sea vegetables can help to lower blood pressure. The dietary
fiber of sea vegetables, in addition to assisting in clearing the
digestive system, also protects the surface membrane of the stomach
and intestine from potential carcinogens and absorbs various substances
such as sodium ions and cholesterol, ultimately to be eliminated.
Dietary fibers which are high in the absorption of water are found
aplenty in edible sea vegetables such as kombu, wakame. These seaweeds
contain a sulfate polysaccharide known as fucoidan. In addition,
kombu and wakame contain alginates, a polyuronic acid which is also
a water-soluble dietary fiber. These types of acidic dietary fibers
are generally not present in terrestrial vegetables. Sea vegetables
contain more of the acidic polysaccharides which are soluble in
water or dilute alkali.
2. Antihypertensive substances
Hypertension, simply stated, is when the blood pressure is elevated,
especially, at the lower reading or diastolic pressure. There are
various reasons why the blood pressure may be elevated but obesity
and high levels of sodium may aggravate this condition. Since ancient
times, it has been known in Japan that a diet of sea vegetables
had the effect or lowering blood pressure. In recent laboratory
experiments results show that incorporating sea vegetables to the
diet of rats effectively lowers blood pressure. Blood pressure is
regulated by the balance between sodium and potassium ion levels
in the blood. With an increase in sodium ions, the autonornic nerves
give orders for vasoconstriction. With the lowering of sodium ions
and increasing potassium ions, blood pressure is lowered. Most of
sea vegetables and particularly polysaccharides isolated from them
have been known to show high dietary fiber activities such as somewhat
noticeable hypotensive material when they are ingested as food.
3. Cholesterol
Cholesterol is a common word in today's vernacular and most people
are aware of what their cholesterol levels are. Also known are the
facts that when cholesterol levels are high, this can lead to serious
heart problems. Low density lipoproteins (LDL) carries cholesterol
that can build up plaque in the arteries and high-density lipoproteins
(HDL) carries cholesterol to the level where the body can get rid
of it. Research evidence in Japan show that there is a distinct
link between the lowering of blood cholesterol level and the prevention
and reduction of plaque buildup in the arteries and the ingestion
of certain sea vegetables. It shows that most of the sea vegetables,
for example, aonori, kombu, wakame, and nori elevated the HDL levels
and depressed LDL levels in the blood for the test animals. In particular,
a diet containing sea vegetable polysaccharides which have a high
function of dietary fiber showed this remarkable tendency. When
sea vegetables are ingested in the intestine, the dietary fibers
themselves gradually from a colloidal state in a random network
of the polysaccharide molecules. Part of cholesterols whether they
are exogenous or endogenous get wrapped up in this network and move
through the diogstive tract, finally to be eliminated. Thus, cholesterol
to be absorbed may become lesser. These sea vegetables have long
been used a part of Japanese diet.
4. Thrombosis and Anticoagulants
When we get a cut or wound and bleeding occurs, the blood has a
protective mechanism by which the bold clots and the bleeding stops.
The bleeding stops because in a series of enzymatic reactions following
the blood coagulation. If there is a lesion in the vessel and the
clot or thrombosis is formed in the vessel, the results can be very
serious, especially if the clot is in the cerebral or coronary arteries.
On the other hand, there is an enzyme called plasmin which degrades
blood clots and improves blood stream. Plasmin is a kind of serin
protease and found in the tissues of the vessel walls and in urine.
Plasmin is produced from a precursor called the plasminogen activating
enzyme (PAE). Plasminogen is a type of protease. Fucosterol, a substance
which occurs naturally in sea vegetables has recently been found
to activate PAE and accelerate the formation of plasmin.
5. Diabetes
Diabetes is a complex disorder in metabolism when a person is not
able to properly digest sugar, either due to a partial or total
lack of insulin or the inability of insulin to carry out its normal
function. Insulin is a hormone secreted by the Islets of Langerhans
in the pancreas. When blood glucose level is elevated in normal
body, insulin is secreted into blood to accelerate glucose degradation
in certain tissues and glycogen formation in other tissues. This
results in the lowering of glucose levels in the blood. A protein
which exhibits similar function to insulin was isolated from sea
vegetables. Also, foods high in dietary fibers are effective in
lowering glucose levels in the blood stream.
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