Despite the perception that organic food, that has been grown without the use
of artificial fertilisers, pesticides and other chemicals, is more somehow
purer, more nutritious and virtuous, scientists have said there is little
evidence that it is healthier.
A review of 237 research studies into organic food found the products were 30
per cent less likely to pesticide residue than conventionally grown fruit
and vegetables but were not necessarily 100 per cent free of the chemicals.
They found no consistent differences in the vitamin content of organic
products.
There were higher levels of phosphorus in organically grown food but the
researchers said this is of little importance as so few people are deficient
in this.
The only other significant finding was that some studies suggested that
organic milk contained higher levels of omega-3 fatty acid, which is thought
to be important for brain development in infants and for cardiovascular
health.
Dr Crystal Smith-Spangler, a teacher at Stanford's Centre for Health Policy,
said: "Some believe that organic food is always healthier and more
nutritious,.
"We were a little surprised that we didn't find that."
"Our goal was to shed light on what the evidence is.
"This is information that people can use to make their own decisions
based on their level of concern about pesticides, their budget and other
considerations."
She said the overall message was that people needed to eat more fruit and
vegetables, no matter how they were grown, because most Western diets are
deficient.
The research was published in the journal, Annals of Internal Medicine.
Dr Dena Bravata, a senior affiliate with Stanford's Center for Health Policy,
said: "There isn't much difference between organic and conventional
foods, if you're an adult and making a decision based solely on your health.
"If you look beyond health effects, there are plenty of other reasons to
buy organic instead of conventional."
She said taste, concerns about the effects of conventional farming practices
on the environment and animal welfare as some of the reasons people choose
organic products.
The group found two studies comparing children consuming organic and
conventional diets did find lower levels of pesticide residues in the urine
of children on organic diets, though the levels of urinary pesticides in
both groups of children were below the allowable safety thresholds.
Also, organic chicken and pork appeared to reduce exposure to
antibiotic-resistant bacteria, but the researchers said the health
implications of this were not clear.
The group said the research was difficult because of the various ways organic
food was tested, other factors that affect nutrient levels such as soil and
weather and the effect that organic farming methods may have such as using
manure as fertiliser which may carry bacteria.
Prof Alan Dangour, senior lecturer at the Nutrition and Public Health
Intervention Research Unit, at the London School of Hygiene and Tropical
Medicine, said: “The Smith-Spangler paper is a careful and detailed review
of reports. It again demonstrates that there are no important differences in
nutrient content between organic and conventionally produced foods.
"The Smith-Spangler paper also reviews health benefits of organic foods
and like our 2010 review finds no evidence that organic foods are healthier
than conventionally produced foods.
“However, throughout the paper the authors make it clear that the evidence
base is weak and highly variable.
“Consumers select organic foods for a variety of reasons, however this latest
review identifies that at present there are no convincing differences
between organic and conventional foods in nutrient content or
health-benefits."
A spokesman for the Soil Associaiton said: "This US study, of limited
application in Europe, found organic food helps people avoid pesticides in
their food, recognised that organic milk has significantly higher levels of
beneficial nutrients, and says that the market for organic food is still
‘skyrocketing’ in America. Significantly, given the rising concern about
antibiotic resistance, the study found that the risk of bacteria resistant
to three or more antibiotics was higher in non-organic than in organic
chicken and pork.
"However, the study only reviewed some existing studies, and omitted many,
including all those not written in English.
"The scientific methodology used for the review, while suitable for comparing
trials of medicines, is not right for comparing different crops.
"A UK review paper, using the correct statistical analysis, has found that
most of the differences in nutrient levels between organic and non-organic
fruit and vegetables seen in this US study are actually highly significant.
"As the study says, there are almost no long-term studies of the impact on
people’s health of eating organic food, but the study does mention one Dutch
Government funded long-term research project, which found that children who
consumed dairy products of which more than 90 per cent were organically
produced had a 36 per cent lower risk for eczema at age 2 years."
source :The Telegraph
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