The organic market continues to grow year on year worldwide, generating a whopping 90 billion euros in 2017 (1). UK supermarket sales of organic food rose by 4.2% in 2018, whilst non-organic sales increased by just over 2% (2). Health, animal welfare and environmental concerns seem to be the principal motives for this growing trend but given the costs of organic foods are consistently higher than non-organic, for example organic carrots are 30-64% higher, strawberries: 32-57% and apples 40-42% (3), are they worth the extra money?
Before I begin, I must make it clear that I’m reviewing this from a purely nutritional perspective and examined just fruit and vegetables. There are of course other perspectives and arguments, but no one negates the other.
Firstly, let’s find out a little more about organic farming and how it differs from conventional… IFOAM defines organic farming as “a production system that sustains the health of soils, ecosystems and people.” It relies on ecological processes, biodiversity and cycles adapted to local conditions, rather than the use of inputs with adverse effects” (4).
In the UK, up until the 31st December 2020, organic food is still produced under rules set by the EU. Once strict conditions around production, transportation and storage have been fulfilled and a company is certified as organic by an authorised control agency, the below logo can be used. Manufacturers continue to be audited at least once a year to ensure they follow the appropriate regulations.
The key principles of organic farming include the exclusion of genetically modified organisms (GMOs i.e. plants in which the genetic material has been manipulated) and the limited use of artificial fertilisers, herbicides and pesticides. Organically approved versions are allowed (5).
Both organic and conventional farming use some similar practices, such as crop rotation and the use of manure. Conventional farming may also avoid using synthetic fertilizers where possible. In the UK, between 2016-2018, the pesticide-treated area for soft fruit decreased by 1%, despite a 7% increase in the growing area. Pesticides used on orchards decreased by 20% between 2014-2018 (6)
Maximum Residue Levels (MRLs) of pesticides on food have been established in conjunction with the EU and these apply to most food. These are different to safety limits and are always set below levels that would present a risk to consumers. This data is available from: https://secure.pesticides.gov.uk/MRLs (7)
So this leads us into our first question…Do organic fruit and vegetables have lower levels of pesticides than conventionally farmed fruit and vegetables?
A review of the evidence conducted last year, found that some studies have shown that organic vegetables had significantly less amounts of contaminants (nitrates, heavy metals and pesticides) than non-organic. However, there were also studies that didn’t find any differences and some that found pesticides in organically grown carrots, for example, that were above the limit (8). A few studies compared pollutant levels in organic and non-organic foods, resulting in the review concluding that the “Organic label literally means that pesticides, synthetic fertilisers, hormones and antibiotics must not be used along the agriculture/farming system. However, organic food certification does not mean that foodstuffs are free of environmental contaminants”, such as those from traffic, bushfires and chemical industries (8). The European Food Safety Authority (EFSA), who provides an annual report which analyses pesticide levels in foods on the European market, found that while MRL exceedance rates are very low overall, they are higher for conventionally grown vegetables. In 2018, the MRL rates were 6.4% for non-organic vegetables and 2% for organic. Some of the pesticides present in the organic vegetables were not authorised for use in organic farming and were believed to have occurred secondary to factors, such as; spray drift, environmental contaminations or contamination during handling, packaging, storage or processing (9). A few years back, small cross-over studies in children identified that urinary metabolites of certain pesticide residues decreased when organic fruits and vegetables were eaten but because of these studies, the use of these pesticides are in strong decline. The risk for E. coli contamination of organic foods may be slightly higher than conventionally farmed foods (10).
Is there a difference in nutrition between organic and conventionally produced fruit and vegetables?
Again the results are mixed, while a few studies indicate there’s no consistent evidence to support the nutritional benefits of organic plant foods, other studies have identified differences, which include: higher levels of calcium, potassium, magnesium, iron, phosphorous, vitamin C, Vitamin E, phenols, carotenoids and antioxidant levels in organic foods (10-11). However, these differences are likely to be small when considering overall dietary intake and thus not clinically meaningful.
Are there taste differences between organic and conventionally farmed produce?
There doesn’t seem to be enough research in this area but consumers commonly think organic foods tastes better. This may be due to factors such as: differences in plant varieties and a shorter time period between harvesting and consumption in organic fruit and vegetables that may affect taste (10).
Now for the big one - Are there any health benefits of eating organic food over conventionally farmed food?
Whether any of the differences mentioned above are relevant for human health is still not clear. The variances are mostly small and thus may not be of practical relevance in well-nourished populations. The EFSA very recently published the results of two pilot assessments on the risks of residues of multiple pesticides in food on our thyroid and nervous systems. The overall conclusion for both assessments was that, with varying degrees of certainty, risk was below the threshold that triggers any regulatory action. Further studies on other body organs and functions will be carried out later in the year (12). While the odd study has claimed very strong benefits, their methodology has been shown to be flawed or based on observational studies only. Furthermore, many consumers who purchase organic food, have specific socio-demographic characteristics, lifestyles and food patterns, which make it much harder to draw any firm conclusions.
As the evidence is limited, it’s impossible to say that organic fruit and vegetables are healthier or provide any additional benefits over non-organic fruit and vegetables. Simply including fruit and vegetables in a balanced diet, regardless of whether the produce is organic, remains most important and is based on strong evidence. So, if you want to go organic (by all means do so) but don’t feel you have to/should do, particularly as for many it’s an expense too far.
1. IFOAM Organics International. Consolidated Annual Report of IFOAM Change for good 2018 [online, accessed 26/5/20] Available from https://www.ifoam.bio/sites/default/files/2020-03/annualreport_2018.pdf
2. Soil Association 2018 The 2018 Organic Market Report [online, accessed 26/5/20] Available from https://www.soilassociation.org/certification/trade-news/2018/organic-has-reached-its-highest-sales-ever-at-over-22b/
3. Tesco, Waitrose, Sainsburys Supermarkets data [online, accessed 26/5/20] Available from https://www.google.com/search?q=waitrose&oq=waitrose&aqs=chrome.0.69i59j0l6j69i61.2071j0j4&sourceid=chrome&ie=UTF-8, https://www.tesco.com/groceries/, https://www.sainsburys.co.uk/
4. International Federation of Organic Agriculture Movement. Definition of organic agriculture. [online, accessed 26/5/20]. Available from: http://www.ifoam.org/en/organic-landmarks/definition-organic-agriculture
5. European Commission Organic production and products [online, accessed 26/5/20]. Available from: https://ec.europa.eu/info/food-farming-fisheries/farming/organic-farming/organic-production-and-products_en
6. Fera Recent pesticide usage surveys 2018 [online, accessed 26/5/20]. Available from: https://secure.fera.defra.gov.uk/pusstats/surveys/2018surveys.cfm
7. Health and Safety Executive Maximum Residue Level (MRL) Database 2020 Available from https://secure.pesticides.gov.uk/MRLs/Main
8. González N, Marquès M, Nadal M, Domingo J.L (2019) Occurrence of environmental pollutants in foodstuffs: A review of organic vs. conventional food. Food and Chemical Toxicology 125 370–375
9. European Food Safety Authority The 2018 European Union report on pesticide residues in food. Available from https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2020.6057
10. PEN The Global Resource for Nutrition Practice. Organic food background and summary of recommendations and evidence [online, accessed 26/5/20. Available from: https://www.pennutrition.com/index.aspx?logout=1
11. Brantsæter AL, Ydersbond T.A, Hoppin J.A, Haugen M and Meltzer H.M. (2017) Organic Food in the Diet: Exposure and Health Implications Annu. Rev. Public Health. 38:2.1–2.19
12. European Food Safety Authority. Pesticides: first cumulative risk reports published 2020 Available from: http://www.efsa.europa.eu/en/news/pesticides-first-cumulative-risk-reports-published