Agriculture Reference
In-Depth Information
beneficial microbial flora in the lower digestive tract. Finally, alliums can
substitute selenium for sulfur absorption in selenium-rich soils and, being rich in
sulfur-containing substances as well as widely consumed, they may be useful for
increasing dietary selenium intake, which would be beneficial to health in
regions like the UK, where mean selenium intake is low.
Examples from different types of research indicating
health benefits
Epidemiology
1.
Comparisons on adherents to Jainism in India, who either abstain from
eating onions and garlic, eat moderate amounts (< 200 g of onion, < 10 g of
garlic per week) or eat large amounts (> 600 g onion, > 50 g garlic per week),
showed that the allium eaters showed: (i) less tendency to form blood clots; and
(ii) lower levels of cholesterol and the lipoproteins associated with heart disease
in their blood serum than the abstainers.
2.
In Jiangsu province, China, where oesophageal and stomach cancer are
common, the intake of allium vegetables was found to protect against these
cancers.
3.
A strong inverse association between the onion consumption and the
occurrence of stomach cancer was found in a large survey of diet and cancer
from The Netherlands.
Clinical interventions
1.
Adult volunteers suffering from allergic bronchial asthma were treated
with a dilute ethanol extract of sliced onions before being exposed to an inhaled
allergen. The asthmatic reactions in the bronchi were markedly reduced.
2.
Administration of garlic powder improved peripheral arterial circulation in
patients diseased in this respect and improved their walking. In a separate study,
garlic powder improved subcutaneous microcirculation in healthy subjects.
3.
Administration of garlic or garlic extracts to patients with high blood
cholesterol resulted in a 10-15% reduction, a similar effect to prescribing a
near cholesterol-free diet.
Animal studies
1.
In guinea pigs with induced bronchial constrictions analogous to asthma,
oral treatment with freeze-dried onion juice counteracted the constrictions.
Thiosulfinates and cepaenes were the active compounds.
2.
Garlic powder reduced blood cholesterol, lipids and blood pressure in rats
with high cholesterol.
