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, poppy seeds
fresh herbs
celery, grapefruit, okra, leafy vegetables (salad, kale, spinach, greens etc), turnips, vine leafs
tea (including herbal tea)
dry lentils

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 deteriorate over time.

Meat

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).