Jan 14, 2009 (foodconsumer.org) -- A new study by
researchers at the
California Berkeley suggests
that high intake of vitamin C may help prevent high blood pressure in young
The study published in the open-access Nutrition Journal
found that each 1 mg/dL increase in serum vitamin C was linked to a drop of 4.1
and 4.0 mmHg in systolic and diastolic blood pressure respectively.
For the study, Gladys Block and colleagues examined the
association between serum vitamin C levels, which ranged from 0.22 to 3.13
mg/dL, and blood pressure in 242 women aged 18 to 21 of whom two thirds were
African-American and the rest Caucasian.
During the 10-year follow-up, the researchers found in young
women serum vitamin C levels were inversely associated with both systolic and
diastolic blood pressure. The associations were significant even after
cofounders were also considered.
Specially, systolic and diastolic blood pressures in women with
the highest serum vitamin C were 4.66 mmHg and 6.04 mmHg lower respectively
compared to those with the lowest levels.
An early Italian study found that vitamin C intravenously
delivered can lower blood pressure by acting on an overactive central nervous
Dr. Rosa Maria Bruno from the
coauthor of the study, said quoted by healthday.com, "our study
demonstrated for the first time in humans that we can reduce sympathetic
nervous system over-activity, and consequently blood pressure, (by) targeting
The sympathetic nervous system (SNS) is part of the central
nervous system that controls blood pressure among other things.
Low activity of the SNS is coupled with the
onset of elevated blood pressure.
The finding was presented Friday at the American Heart
Association's Conference of the Council for High Blood Pressure Research held
The current study involved 12 patients with an essential
form of high blood pressure who had not received any treatment for their high
All the participants
were intravenously administered three grams of vitamin C during a period of
five minutes and then monitored for blood pressure and SNS activity for 20
It was found that SNS activity dropped by 11 percent and
blood pressure was lowered by about 7 percent on average.
The decrease in diastolic blood pressure was
9 percent while systolic blood pressure did not change significantly.
Vitamin C is known to boost the production of nitric oxide,
which can affect blood vessels and lower blood pressure, early studies
Nitric oxide (NO) contributes
to vessel homeostasis by inhibiting vascular smooth muscle contraction and
growth, platelet aggregation, and leukocyte adhesion to the endothelium,
according to wikipedia.