WSU, Harvard scientists slam Stanford organic health claims
Stanford University researchers recently made the conclusion there was not enough evidence to suggest organic food was healthier to eat than conventional products. The interpretation of the meta-analysis - meaning it drew on existing publications - was "flawed in several ways", according to Washington State University (WSU) agricultural professor Dr Charles Benbrook in a reflection paper. Harvard School of Health associate professor Dr Alex Lu told www.freshfruitportal.com the study lacked a sound scientific basis, while for Organic Trade Association (OTA) executive director Christine Bushway it merely reinforced the reasons why consumers chose organic food.
Benbrook said he had read more than two thirds of the reference studies cited in the Stanford study, yet he viewed their health implications in a very different way.
"The findings of this study are ripe for overstatement and misinterpretation," he said.
"In the case of pesticides and antibiotics, the indicator used – the percent of samples of organic food with a trait minus the percent of conventional samples affected – is not a valid indicator of human health risk.
"In its analysis the team does not tap extensive, high quality data from the USDA [United States Department of Agriculture] and Environmental Protection Agency (EPA) on pesticide residue levels, toxicity and dietary risk."
He said very few studies were designed in a way that could isolate the impact or contribution of a switch to organic food from the many factors that can influence someone's health.
"Studies capable of doing so would be very expensive, and to date, none have been carried out in the U.S.
"For most people, just switching to organic fruits and vegetables, or organic dairy products or meat, in the absence of other changes in food choices and overall diet quality, would not be expected to trigger a clinically significant improvement in health."
He added this was especially the case given the relatively short time periods in the studies reviewed by the Stanford team, but there was an example used that illustrated the benefits of organic food.
"The one exception in the literature – studies spanning the duration of a woman’s pregnancy and the first few years of a child’s life – provide encouraging evidence that organic food can reduce the odds of some adverse health impacts, including birth defects, neuro-behavioral and learning problems, autism, and eczema," he said.
For Harvard's Dr Lu, whose 2006 study on the effects of organic food switches for children was cited by Stanford, the conclusions of the meta-analysis were disturbing.
"What bothers me is that they've left out other studies that show the difference between organic food and conventional food in terms of the impacts on nutrition," he said.
"The other point that really bothers me is the conclusion that the presence of pesticides in a person's body does not produce any adverse health impacts."
Lu's study was carried out over 2003 and 2004, testing the impacts of schoolchildrens' switch to organic food from conventional. From 450 samples, the study found there were significantly higher levels of pesticides in the urine of kids who consumed conventional foods.
"The question then is whether that's going to make a difference and whether eating organic is going to help - it's a question that's in a lot of people's minds, and my mind too.
"The Stanford scientists acknowledge no study has ever been done to find the answer to this question, so what they're saying is that science is lacking.
"I found it a bit unsolid; their message that it doesn't matter whether you consume conventional or organic food is scientifically unsound."
Benbrook added for individuals already consuming a balanced diet of healthy food with ample servings of fruit and vegetables, a "strategic selection of organic foods can help them further tip the odds towards good health". This is particularly the case at stages in life when people are more vulnerable to the impacts of pesticides and animal drugs.
Nutrition not 'organic's claim to fame'
OTA executive director Christine Bushway said a lot of interpretations of the Stanford study were misleading by highlighting the lack of significant nutritional benefits.
"Organic was never intended to be some enhancer; even the study itself cites several higher levels of phenols in organic produce, and omega 3 and fatty acids in organic chicken, and so we know that there are some higher levels of nutritional benefit.
"There’s the question of how much nutritional benefit do you need, but that’s not organic's claim to fame. Your true organic consumer is buying to avoid pesticides, GMOs and antibiotics in particular.
She highlighted two years ago the President's Cancer Panel had one of its primary recommendations for avoiding the disease as avoiding pesticides in food.
"So I continue to see in this study the benefit that consumers see from avoiding pesticides, because organic has lower pesticide residues, period."
An OTA release highlighted one key finding of the study that showed conventional produce carried a 30% higher risk of pesticide contamination than for organic produce.
"We are optimistic that in the future, good applied scientific research on organic food and farming will show that healthy soils produce healthy foods."