With an ideal ratio of omega-6 and -3 fatty
acids and some plant chemicals thought to lower high blood pressure, hempseed
oil has potential as part of a heart-healthy diet, according to Spanish
They analysed the makeup of oil extracted
from Cannabis sativa, often called industrial hemp, which is a cousin of
marijuana but with very low levels of the chemical in pot that provides a high.
"This is an interesting study that
gives new information on the bioactive compounds found in hempseed that may
potentially lower blood cholesterol levels and have an anti-atherogenic action,"
Grant Pierce told Reuters Health in an e-mail.
Pierce is executive director of research at
St. Boniface Hospital in Winnipeg, Manitoba, Canada. He was not involved in the
new study. Cannabis sativa L., an annual herbaceous plant, is known by its long,
thin flowers and spiky leaves.
Native to Asia
The plant is considered to be native to
western and central Asia and has also been cultivated commercially in Europe
and in parts of China, Japan, Canada, and the United States," write Maria
Angeles Fernández-Arche, a pharmacology researcher at the University of
Seville, and her colleagues.
In addition to a 3000-year track record in
the manufacture of cloth and paper, hemp has long history as a food and folk
medicine, they point out in the Journal of Agricultural and Food Chemistry.
Hempseed is known to have high levels of
vitamins A, C and E, minerals and fibre, the researchers say. But they wanted
to analyse hempseed oil to better understand its potential for modern food and
Hempseed oil has a very interesting
polyunsaturated fatty acid composition, Fernández-Arche told Reuters Health in
an e-mail, because it has an optimal omega-6 to omega-3 ratio of about 3 to
1. Her main area of research is natural products and the bioactive compounds
The researchers examined the fatty acid
profile of hempseed oil and found that polyunsaturated fatty acids (PUFAs) made
up about 75% of the oil. PUFAs include omega-6 and omega-3, the fatty acids
found in some meats as well as flax and fish oils.
Potential to prevent heart disease
The high amounts of one omega-3 fatty acid,
alpha linolenic acid, "may have favourable nutritional implications and
beneficial physiological effects on the prevention of coronary heart disease
and cancer," the authors write.
Saturated fats and monounsaturated fatty
acids each amounted to about 12% of the oil.
A high ratio of polyunsaturated to
saturated fats has been linked to reductions in cholesterol levels and
atherosclerosis, so the proportions seen in hemp oil have the potential to help
prevent heart disease, the researchers write.
They also detected plant chemicals, such as
beta-sitosterol and campesterol, which have been linked to lower heart attack
risk, and reduced LDL cholesterol (the bad kind). Sterols may also lower
inflammation and slow the progression of atherosclerosis, the team notes.
This study doesn't prove that hempseed oil
has any clinical benefits yet – that will take additional research with human
subjects, they point out.
Fernández-Arche said, however, that her
team is studying "the effect of the intake of this oil and this effect on
the stress induced in animals, and the preliminary results are very
promising." Pierce, who has studied the health effects of both flax and
hemp seeds, says of hemp, "It has several potentially important bioactive
compounds that could have beneficial cardiovascular effects. It is a very heart-healthy seed and oil.
"He noted that hempseed oil contains
less oleic acid than other heart-healthy oils, such as olive or canola oil, but
added that studies on animals indicate hempseed might reduce the clotting of
blood platelets that lead to heart attacks.
Pierce thinks flaxseed oil has more health
benefits than hempseed oil. "In our animal experiments, flaxseed has shown
more potent cardiovascular effects than hempseed," he said.
"We have also shown significant blood
pressure lowering effects of flaxseed in human trials," he noted. But to
be fair, he added, hempseed has not had similar trials conducted in humans.
Picture: Hempseed from Shutterstock
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