CEs column: Organic or conventional our food has to be safe

The publication of two British studies which found no significant differences in the health effects or nutritional value of organic and conventional foods has produced the predictable flurry of heated media and blog commentary.

NZFSA’s British counterpart, the Food Standards Agency (FSA – with whom we share science), commissioned the independent studies as part of its role to provide accurate, scientifically-robust information so people can make informed choices about food.

The New Zealand Food Safety Authority (NZFSA), like the FSA, has no view one way or the other about whether people should choose between organic or conventional produce. Consumers make food purchasing decisions based on one or a variety of reasons that matter to them. Choices might be based on the price and availability of food, health and nutrition considerations, country or region of origin of the product, environmental sustainability, corporate responsibility, cultural importance, animal welfare, and labour practices in the production of, and trade in, food.

As a science-based government regulator, NZFSA’s concern is that decisions based on the risks to one’s physical health from any foods – no matter how they are produced – are based on solid scientific evidence and that potential risks are identified and managed. Indeed, we provide official government assurances around organic produce for export, just as we do for conventional produce. Our role is the same for both – to ensure the food is safe and suitable for its intended use, and that it complies with New Zealand rules and with the agreed requirements of the importing countries.

The British findings support our position that there is no conclusive evidence to suggest that organic food is more or less safe or nutritious than conventionally-produced foods and so poses no greater risk or benefit to physical health.

The FSA report was a ‘systematic review’ of articles over the past 50 years on the purported health benefits of organic produce. This means that before it started, the reviewers specified how they would search for evidence, what databases they would use, what types of studies would be considered, and how they would grade the quality of the papers being reviewed. In essence they would only take into account good quality studies that had been published in peer-reviewed academic journals – sound science.

What I did find interesting was that after sorting by these clearly defined and transparent criteria, only about a third of studies reviewed were sufficiently robust to be considered. In one of the studies (on health benefits) this amounted to 11 papers; in the second study (comparing the nutrient content of organically and conventionally produced food) just 55 fitted the bill. This indicates an alarming dearth of reliable science around some of the claims about organic foods, in my view.

A recent study published in the British Food Journal (2009, Vol 111, Issue 10) also noted the lack of good science, and identified a gap between consumer perception on the health effects of organic produce and scientific evidence:

“Organic vegetables are perceived as containing less contaminants and more nutrients, and as such, as being healthier and safer compared to conventional vegetables. However, not enough evidence is currently available in literature to support or refute such perception, indicating a certain mismatch between consumer perception and scientific evidence.”

NZFSA treats organic food in the same way as all other foods. The same risk management framework for assessing safety and suitability is applied to all food for sale here, including organic food and all products used in its production such as agricultural and veterinary compounds, which we regulate.

The British studies noted some differences between various organic and conventional fruits and vegetables of specific nutrients, but not so much as to offer extra health benefits either way. Of course, nutrient levels can be affected by variables such as ripeness, choice of cultivar, distance to market, storage, and exposure to light, as well as how, where and when the food is produced.

The pro-organics lobby contends that it is not what is in organic food, in terms of nutrition, it is what is not in organic food that makes it better. That might not be especially evident from the way advertisers and marketers appeal to consumers around the alleged benefits of organics. Despite that disparity, the use of pesticides, herbicides, fertilisers, and veterinary medicines in all food is strictly regulated in New Zealand. Any residues due to the use of these agricultural compounds are at levels that present notional zero risk to consumers. The term ‘notional zero risk’ describes the risk associated with consuming levels of substances below the acceptable daily intake (ADI). This is the level at which a substance can be consumed every day for a whole lifetime without noticeable effect. In all respects, agricultural compounds allowed for use in certified organic systems are subject to the same risk management requirements as those used in conventional systems.

As the use of agricultural compounds in both organic and conventional produce are regulated and monitored so that residues pose notional zero risk, the inevitable conclusion from the weight of evidence is that there is no measurable health benefit to be gained by eating organic produce.

Just because organic production uses ‘natural’ as opposed to synthetic agricultural compounds does not make it inherently safer. Organic agriculture uses composted manures as fertilisers. And, while composting is effective in reducing the levels of harmful bacteria such as E. coli 0157, it is not always failsafe.

Labelling a product ‘organic’ is optional but under our consumer protection laws must, if used, be truthful. What this means in reality is that there is an expectation that if a product is represented as organic, all ingredients used to make the product should be 100% organic.

With the relative merits of organic versus conventional produce so indistinct, I would reinforce the important health message that people eat the recommended portions of at least three servings of vegetables and two servings of fruit a day, no matter the method of production.

The NZFSA policy statement and comprehensive background paper on organic food are available for anyone who wants more detailed information on the rationale behind our policy.