Hành không chỉ
là thực phẩm gần gũi với con người mà nó còn là vị thuốc chữa bệnh rất
công hiệu, tốt cho người mắc bệnh về đường hô hấp, bệnh hen suyễn, chứng
mất ngủ và giảm cholesterol.
Dưới đây là 10
tác dụng của hành vừa được công bố trên Tạp chí Y học HeathMad của Mỹ số
ra tháng 7/2010.
- Các hợp chất tự nhiên có trong
hành có tác dụng làm dịu những cơn ho, long đờm và khử đờm rất hiệu
quả.
- Hành tốt cho
nhóm người mắc bệnh hen suyễn, viêm phế quản, lao, viêm xoang và các
chứng bệnh nhiễm trùng về đường hô hấp.
- Hành tây có tác
dụng hạ huyết áp, có lợi cho tim mạch.
- Theo nghiên cứu
thì hành có tác dụng giảm cholesterol (mỡ máu), giúp cho máu lưu thông
tốt. Hạn chế cholesterol xấu và làm tăng cholesterol tốt
(HDL).
- Hành là thực
phẩm kiêm dược phẩm tốt cho hệ thống tiêu hoá, chống táo bón, đầy hơi và
trào ngược axít dạ dày.
- Hành tây là
thực phẩm tốt cho nhóm phụ nữ mắc bệnh mất kinh, vàng da và liệt sức vì
nóng, vì vậy những người ốm mệt có thể ăn cháo hành và phát huy tác dụng
tức thì.
- Hành các loại,
kể cả hành tây có mức độ sát trùng rất mạnh, vì vậy có khả năng ngăn
ngừa các chứng bệnh viêm nhiễm đường ruột rất hiệu quả.
- Nước ép hành
trộn với mật ong nguyên chất có tác dụng chữa bệnh khản tiếng và ho rất
tốt.
- Nước ép hành có
tác dụng làm lành vết thương hạn chế mưng mủ do tác dụng kháng khuẩn có
trong hành.
- Nước ép hành và
tỏi có tác dụng tích cực trong việc chống mất ngủ. Sau khi giã nhỏ hành
tỏi, sau đó pha vào nước ép trái cây để uống. Mỗi cốc nước trái cây pha
thêm 3-4 thìa nước ép hành, uống trước khi ăn hoặc trước khi đi
ngủ.
Onions are Beneficial for Your Health
Onions are beneficial to health
What would life be like without onions? The onion has been
used as an ingredient in various dishes for thousands of years by many
cultures around the world. World onion production is steadily increasing
so that onion is now the second most important horticultural crop after
tomatoes.
There are many different varieties of onion, red,
yellow, white, and green, each with their own unique flavor, from very
strong to mildly sweet. Onions can be eaten raw, cooked, fried, dried or
roasted. They are commonly used to flavor dips, salads, soups, spreads,
stir-fry and other dishes.
Onions (Allium cepa) belong to
the lily family, the same family as garlic, leeks, chives, scallions and
shallots.There are over 600 species of Allium, distributed all over
Europe, North America, Northern Africa and Asia. The plants can be used
as ornamentals, vegetables, spices, or as medicine. There are over 120
different documented uses of the Alliums.
Onion and other Allium
vegetables are characterized by their rich content of thiosulfinates,
sulfides, sulfoxides, and other odoriferous sulfur compounds. The
cysteine sulfoxides are primarily responsible for the onion flavor and
produce the eye-irritating compounds that induce lacrimation. The
thiosulfinates exhibit antimicrobial properties. Onion is effective
against many bacteria including Bacillus subtilis, Salmonella, and E.
coli. Onion is not as potent as garlic since the sulfur compounds in
onion are only about one-quarter the level found in garlic.
The Value of Onions
Onions have a variety of medicinal effects. Early American settlers
used wild onions to treat colds, coughs, and asthma, and to repel
insects. In Chinese medicine, onions have been used to treat angina,
coughs, bacterial infections, and breathing problems.
The World
Health Organization (WHO) supports the use of onions for the treatment
of poor appetite and to prevent atherosclerosis. In addition, onion
extracts are recognized by WHO for providing relief in the treatment of
coughs and colds, asthma and bronchitis. Onions are known to decrease
bronchial spasms. An onion extract was found to decrease allergy-induced
bronchial constriction in asthma patients.
Onions are a very
rich source of fructo-oligosaccharides. These oligomers stimulate the
growth of healthy bifidobacteria and suppress the growth of potentially
harmful bacteria in the colon. In addition, they can reduce the risk of
tumors developing in the colon.
Cardiovascular Help
Onions contain a number of sulfides similar to those found in
garlic which may lower blood lipids and blood pressure. In India,
communities that never consumed onions or garlic had blood cholesterol
and triglyceride levels substantially higher, and blood clotting times
shorter, than the communities that ate liberal amounts of garlic and
onions. Onions are a rich source of flavonoids, substances known to
provide protection against cardiovascular disease. Onions are also
natural anticlotting agents since they possess substances with
fibrinolytic activity and can suppress platelet-clumping. The
anticlotting effect of onions closely correlates with their sulfur
content.
Cancer Prevention
Onion extracts, rich in a variety of sulfides, provide some
protection against tumor growth. In central Georgia where Vidalia onions
are grown, mortality rates from stomach cancer are about one-half the
average level for the United States. Studies in Greece have shown a high
consumption of onions, garlic and other allium herbs to be protective
against stomach cancer.
Chinese with the highest intake of
onions, garlic, and other Allium vegetables have a risk of stomach
cancer 40 percent less than those with the lowest intake. Elderly Dutch
men and women with the highest onion consumption (at least one-half
onion/day) had one-half the level of stomach cancer compared with those
consuming no onions at all.
Western Yellow, New York Bold, and
Northern Red onions have the richest concentration of flavonoids and
phenolics, providing them with the greatest antioxidant and
anti-proliferative activity of 10 onions tested. The mild-tasting
Western White and Vidalia onions had the lowest antioxidant content and
lowest anti-proliferative activity. The consumer trend to increasingly
purchase the less pungent, milder onion varieties may not be the best,
since the onions with a stronger flavor and higher astringency appear to
have superior health-promoting properties.
Use and Safety
Onions have a universal appeal. They are safely consumed by most
people. However, consuming large quantities of onions can lead to
stomach distress and gastrointestinal irritation that may result in
nausea and diarrhea. There are no known interactions with drugs except
that they can potentiate the action of anticoagulants.
Conclusion
Onions, and other Allium species, are highly valued herbs
possessing culinary and medicinal value. Some of their beneficial
properties are seen after long-term usage. Onion may be a useful herb
for the prevention of cardiovascular disease, especially since they
diminish the risk of blood clots. Onion also protects against stomach
and other cancers, as well as protecting against certain infections.
Onion can improve lung function, especially in asthmatics. The more
pungent varieties of onion appear to possess the greatest concentration
of health-promoting phytochemicals.
Author: Winston
Craig, MPH, PhD, RD.