Perhaps in an ideal world, all of our food would be organic, home-grown and eaten within a few hours of picking. But budget, availability, time, space, other commitments, and of course sustainability, remind us with a hefty dose of reality that this is unlikely to become more than an impossible dream for almost everyone.
So, back in the real world, I have tried to put together a list of products which you might decide are worth prioritising to buy organically, and those which perhaps are less important, as well as the reasons why. Of course, it is always better to eat a healthy, balanced, plant-based diet made up of non-organic foods, than it is to eat an unhealthy organic diet. So the first point is that the most important factor in your decision making around buying food should be the foods themselves.
There are also lots of environmental, ethical and farming reasons why some people decide to buy organic produce – which is a whole other topic in itself, so today I am just going to focus on the nutrition side of things. If you want more information, do take a look at the Soil Association website: http://www.soilassociation.org
Fruit & Vegetables
An important study looking at over 300 research papers on organic vs. non-organic crops, concluded that the organic crops had significantly more phytonutrients, but lower levels of pesticide residue and cadmium (a toxic heavy metal) (1). Cadmium is one of three heavy metals, the others being lead and mercury, which have a ‘maximum permitted contamination’ level in food, as set by the European Commission. It accumulates in the body, and can collect in the liver and kidneys. We do not need Cadmium in our diets, so the less we consume, the better.
‘Phytonutrients’ are a group of thousands of beneficial chemicals found naturally in plants, which are not yet established as essential nutrients (like vitamins), but nonetheless have an important role to play in helping maintain health and fight disease. In fact, if you eat your 5-a-day, the higher level of phytonutrients in organic fruit and veg gives the equivalent to an extra 2 portions per day!
Conventionally (non-organically) produced fruit has the highest pesticide residue frequency (65.5%), compared to grains (41.2%) and vegetables (35.1%) (2). Although the EU sets maximum levels of pesticide residues on conventional produce (which is considered to be safe for human consumption), testing often shows that certain products have residues above these maximum levels. What we do not know yet is what effect these residues may have on our health, so I tend to err on the side of caution and avoid them as much as possible.
According to the European Food Standards Agency report on pesticide residue in food, these are their top offenders (i.e., products which had the highest percentage of samples above the maximum limit of pesticide residue) (2). Therefore they are probably the ones most worth trying to buy organically;
- Cumin seeds
- Fresh herbs
- Leafy vegetables (salad, kale, spinach, greens etc)
- Tea (including herbal tea)
- Vine leaves
- Dry lentils
- Poppy seeds
It is worth saying that even organic produce is not completely free from pesticide residue. This is probably because there is often cross-contamination when fields are sprayed, from food handling and packaging. However, the detection rate is generally far less, and very rarely exceeds the maximum limit.
The bottom line? It would be ideal to try to buy as much of your fruit and veg organically as possible to maximise phytonutrients. Often organic vegbox schemes can be a cost-effective way of doing this (not least because it keeps you away from the heady temptations of the supermarket). However, if you need to prioritise, I would start by making sure you try to get at least your fresh herbs, salad leaves and leafy green vegetables organically. Then would come the other ‘top offenders’ I’ve listed above and fruit (especially those which you do not peel), followed by cereals and then other vegetables.
If you cannot buy organically, do make sure that you wash everything well in warm water before eating it, and try to minimise the amount of time that you store your produce after bringing it home – so that you at least you can preserve the maximum vitamin content, which tends to deterioriate over time.
Organic milk contains more healthy omega-3 fats, although considerably less of the essential minerals iodine and selenium than conventionally produced milk (3). This is likely to be more related to the production systems (i.e., breeding, feeds, milking practices) rather than due to it being organic or not. In fact, pasture-fed animals, which are not necessarily ‘organic’, produce milk that is very similar to organic (4). It is worth pointing out that oily fish and plant oils, such as rapeseed, have many more omega-3 fatty acids than milk – which is actually relatively poor source of these important nutrients, so the overall benefit is fairly small.
Milk and dairy products are a key source of iodine in the UK diet, and deficiency in this can cause serious problems to the developing infant in pregnancy. Therefore, it is important to make sure that you have alternative iodine sources in your diet if you only consume organic dairy products. For more information on iodine, take a look at this fact sheet;
The bottom line? Organic or not is a personal choice. If you feel that the organic farming methods are perhaps kinder, or the uncertainty about residual chemicals (antibiotics, pesticides etc.) found in some conventional milks is worrying, or you are swayed by the beneficial fat content, then go for organic milk and dairy products. If you are more interested in maximising your iodine intake (perhaps you are a vegetarian, for example, and therefore do not get it from alternative sources such as meat or fish), then maybe conventional dairy products are better for you.
Although there is still a lot of research to be done in this area, a new study has very recently been published that systematically looked at all the research on organic vs. non-organic meat (5).
It concluded that organic meat contains more of the healthy polyunsaturated fatty acids and omega-3 fats, but lower levels of saturated fats than non-organic meat. These effects, however, were relatively small, and again were likely to be due to the fact that organic animals are raised with more access to outdoor foraging and grass, rather than the more restrictive grain feeding of non-organic animals. It seems it is not just humans who are what they eat!
More research is still needed to assess whether the potentially undesirable chemicals (antibiotics, growth hormones, toxic metals and pesticides) sometimes found in conventionally raised animals, raised both for meat and for dairy production, may have a harmful impact on us. There are a lot of scare stories about, but the science hasn’t made any clear conclusions just yet.
The bottom line? From a nutrition perspective, it is likely that organic meat is slightly healthier than non-organic meat. But if that is not an option for whatever reason, the next best bet is probably to look for pasture-fed, grass-fed or free-range.
Personally, I prefer to eat less meat, but buy top quality, organic meat just occasionally instead (i.e., around once a week for red meat, and once or twice a week for poultry).
(1) Barański, M., Średnicka-Tober, D., Volakakis, N., Seal, C., Sanderson, R., Stewart, G.B. and et al. (2014) ‘Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: A systematic literature review and meta-analyses’, British Journal of Nutrition, 112(05), pp. 794–811.
(2) EFSA (European Food Safety Authority) (2014) The 2012 European Union report on pesticide residues in food 1. Available at: http://www.efsa.europa.eu/sites/default/files/scientific_output/files/main_documents/3942.pdf (Accessed: 16 February 2016).
(3) Srednicka-Tober, D., Baranski, M., Seal, C., Sanderson, R., Benbrook, C., Steinshamn, H. et al. (2016) Higher PUFA and omega-3 PUFA, CLA, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: A Systematic Literature Review and Meta- and Redundancy Analyses. British Journal of Nutrition. In press – Feb 2016.
(4) The Soil Association (2016) Organic vs Non-organic: A new evaluation of nutritional differences: Milk. Available at: http://www.soilassociation.org/LinkClick.aspx?fileticket=511HdacUS80%3d&tabid=2300 (Accessed: 16 February 2016).
(5) Srednicka-Tober, D., Baranski, M., Sea, C., Sanderson, R., Benbrook, C., Steinshamn, H. et al. (2016) Composition differences between organic and conventional meat; a systematic literature review and meta-analysis. British Journal of Nutrition. In press – Feb 2016.