Zeewier tegen overgewicht*
Uit een Engelse laboratoriumstudie blijkt dat zeewier
wel eens een belangrijke voeding kan zijn tegen
overgewicht. Om te kijken hoe voedingsvezels
de opname van vet in de darmen kunnen beïnvloeden werden zestig verschillende
voedingsvezels uitgetest op een kunstmatige darm. De voedingsvezel, alginaat uit
zeewier bleek de opname van vetten wel met 75% te reduceren. Het
hoofdbestanddeel van alginaat is
alginezuur, een polysacharide,
opgebouwd uit mannuronzuur en guluronzuur. Inmiddels hebben de onderzoekers al
op kleine schaal onder mensen onderzoek gedaan door aan brood alginaat toe te
voegen. De eerste resultaten lijken veelbelovend zodat uitgebreide onderzoeken
gewenst zijn.
Fighting The Rising Tide Of Obesity With The Help Of Seaweed
Seaweed could hold the key to tackling obesity after it was found it reduces fat
uptake by more than 75 per cent, new research has shown.
Now the team at Newcastle University are adding seaweed fibre to bread to see if
they can develop foods that help you lose weight while you eat them.
A team of scientists led by Dr Iain Brownlee and Prof Jeff Pearson have found
that dietary fibre in one of the world's largest commercially-used seaweed could
reduce the amount of fat absorbed by the body by around 75 per cent.
The Newcastle University team found that Alginate - a natural fibre found in sea
kelp - stops the body from absorbing fat better than most anti-obesity
treatments currently available over the counter.
Using an artificial gut, they tested the effectiveness of more than 60 different
natural fibres by measuring the amount of fat that was digested and absorbed
with each treatment.
Presenting their findings today at the American Chemical Society Spring meeting
in San Francisco, Dr Brownlee said the next step was to recruit volunteers and
study whether the effects they have modelled in the lab can be reproduced in
real people, and whether such foods are truly acceptable in a normal diet.
"The aim of this study was to put these products to the test and our
initial findings are that alginates significantly reduce fat digestion,"
explains Dr Brownlee.
"This suggests that if we can add the natural fibre to products commonly
eaten daily - such as bread, biscuits and yoghurts - up to three quarters of the
fat contained in that meal could simply pass through the body.
"We have already added the alginate to bread and initial taste tests have
been extremely encouraging. Now the next step to to carry out clinical trials to
find out how effective they are when eaten as part of a normal diet."
The research is part of a three year project being funded by the Biotechnology
and Biological Sciences Research Council. It addresses the new regulations set
out by the European Food Safety Authority that any health claims made on a food
label should be substantiated by scientific evidence.
"There are countless claims about miracle cures for weight loss but only a
few cases offer any sound scientific evidence to back up these claims,"
explains Dr Brownlee.
Alginates are already commonly used at a very low level in many foods as
thickeners and stabilisers and when added to bread as part of a blind taste
test, Dr Brownlee said the alginate bread actually scored higher for texture and
richness than a standard white loaf.
"Obesity is an ever-growing problem and many people find it difficult to
stick to diet and exercise plans in order to lose weight," explained Dr
Brownlee.
"Alginates not only have great potential for weight management - adding
them to food also has the added advantage of boosting overall fibre
content."
What is a dietary fibre?
Dietary fibre would be scientifically classified as a group of carbohydrates of
plant origin that escape digestion by the human gut.
"Actually, there's still quite a lot of confusion about fibre," says
Dr Brownlee. "I think most people would describe it as roughage - the bit
of your food that keeps you regular and is vital for a healthy gut.
"Both of these facts are true but the notion that all fibre is the same and
that it simply goes through your system without having an effect is
wrong."
Fibre is made up of a wide range of different molecules called polysaccharides
and although it is not digested by the human gut, it both directly and
indirectly affects a number of bodily processes.
Dr Brownlee adds: "These initial findings suggest alginates could offer a
very real solution in the battle against obesity."
Source:
Dr. Iain Brownlee
Newcastle University (Mei 2010)
