Over the years there have been conflicting reports on the nutritional benefits of organically farmed produce; with some studies showing little difference in nutrient content between organic and conventional farming. However, there is an increasing amount of evidence in favour of organic foods having a higher content of antioxidants, certain vitamins/minerals and omega-3 fatty acids.
Indeed, an EU Report published in 2016 highlighted that pesticide exposure, bacterial antibiotic resistance and cadmium exposure are major public health issues and organic agriculture may be one way to address these.
With the industrialisation and intensification of farming, conventionally grown crops rely extensively on chemical inputs to achieve high yields. These include synthetic fertilisers containing NPK (nitrogen, phosphorus and potassium), pesticides and herbicides; and antibiotics may be routinely administered to animals.
However, organic systems minimise ‘off-farm’ chemical inputs relying instead on, for example, animal manures and crop rotation to maintain the fertility of the soil. Weeds and pests are mainly controlled through physical and biological control methods.
There are a number of factors that can affect the nutritional quality of food such as climate, soil type and degree of ripeness. Studies comparing organic and conventional systems therefore require that plants are cultivated in similar soils under similar climatic conditions and are sampled at the same time.
The Research Institute of Organic Agriculture in Switzerland (FiBL) summarised the results of seven literature reviews carried out between 1995 and 2003. The conclusion from these studies was that vitamin C and polyphenols (antioxidants) are higher in organic compared to conventional produce. Organic grains had a lower protein content but better protein quality. Some of these studies were criticised because comparisons were not made between crops grown in similar conditions.
However, results from the ‘QualityLowInputFood’ project support these findings. Fruit, vegetables and cattle were farmed on adjacent organic and non-organic sites around Europe. The study is reported to have found that organic fruit and vegetables contain up to 40% more antioxidants and higher levels of minerals such as iron and zinc. Levels of antioxidants in milk from organic herds were up to 90% higher than in milk from conventional herds.
A 2014 meta-analysis of 343 peer-reviewed studies showed the concentration of a range of antioxidants such as polyphenolics to be substantially higher in organic crops – an estimated 19%-69% higher, depending on the specific phenolic. This is because phytonutrients are the plants’ natural defences and plants that are not sprayed with pesticides need stronger defences. They estimated that a switch to eating organic fruit, vegetable and cereals would provide additional antioxidants equivalent to eating between 1-2 extra portions of fruit and vegetables a day.
Some studies have shown that milk and meat from organically farmed livestock have a better fatty acid profile – with higher levels of omega-3 and a lower ratio of omega-6 to omega-3. This is probably due to differences in animal feed. Organic cattle consume more grass and leguminous plants than conventionally reared animals that are fed on grains (which are high in omega-6, low in omega-3). For example, organic milk has approximately 50% more omega-3 fatty acids compared with conventional milk; organic meat a 23% higher omega-3 content.
A study on the mineral content of conventionally grown foods between 1940 and 1991 has shown losses of potassium, magnesium, calcium and trace elements. For example, carrots lost 75% magnesium, 48% calcium, 46% iron and 75% copper over this period. These changes could be due to depletion of the soil itself and excessive use of NPK fertilizers.
Pesticides / herbicides / heavy metals
In 2015, over 17,800 tonnes of pesticides were used on British farms. Conventionally farmed foods have frequently been found to contain pesticide residues:
- One survey found pesticide residues in about 29% of the samples of which 1.6% had levels higher than legally permitted.
- In another, 40% of all non-organic fruit and vegetables tested contained residues. For some fruit and vegetables, the results were over 70%
- Glyphosate is one of three pesticides regularly found in routine testing of British bread, it was detected in over 60% of wholemeal bread samples tested by the Defra committee on Pesticide Residues in Food. Its use in British farming has increased by 700% over the last 20 years. A report by the WHO International Agency for Research on cancer concluded it is a ‘probable carcinogen’
- The 2014 review by Newcastle University of 343 studies found pesticide residues to be four times higher in conventional crops.
Some crops are sprayed with more than one type of chemical and food can contain residues of a number of different pesticides whose effect in combination may be amplified. Whilst most are below the Maximum Residue Levels, from a naturopathic point of view any pesticide residues are undesirable and whilst they may not elicit an acute response, they play a part in the development of chronic illnesses.
Epidemiological studies point to the negative effects of certain insecticides on children’s cognitive development at current levels of exposure. And organic food consumption may be associated with a lower risk of allergies in children. Pesticide exposure in pregnant women is also a concern. On the Soil Association website, Toxicopathologist Dr Vyvyan Howard, a member of the government’s advisory committee on pesticides, is quoted as saying ‘there is sufficient evidence already that the pesticide cocktail effect is producing changes. Exposure to chemicals that disrupt hormones in the womb could be the cause of the decreased age of puberty in girls and early onset of puberty is linked to a greater chance of developing breast cancer later in life.’
In organic agriculture, the use of herbicides and pesticides is restricted. Organic farmers are permitted to use specified pesticides derived from natural ingredients including citronella and clove oil. Organic produce is therefore perceived as pesticide free. However, it may be contaminated from neighbouring farms – more than 99% of all applied farm chemicals miss the target organism. Nevertheless, organic produce has been found to have lower levels of pesticides.
The Research Institute of Organic Agriculture in Switzerland (FiBL) reported no difference in levels of heavy metals between organic and conventionally farmed crops and suggested this is due to ubiquitous environmental contamination from air and water sources. However, others have shown the long-term use of the mineral phosphorus used in fertiliser in conventional farming has contributed to increased cadmium concentrations in agricultural soils. Crops produced by organic farming have comparatively low cadmium concentrations – almost 50% lower in organic crops than conventionally-grown ones. In some cases, the population’s cadmium exposure is above tolerable limits.
There is also the issue of routine antibiotic use in conventionally reared animals. It is legal to use antibiotics prophylactically, ie even when no disease has been diagnosed. This is because intensive production with cramped conditions means disease outbreaks may be more frequent and harder to control. In most countries, more antibiotics are used in animal production than for human health – in European countries antibiotic use in agriculture accounts for almost two thirds of all antibiotics used; in the UK, the figure is around 40%. The reliance on antibiotics is an important factor contributing to increased antibiotic resistance in bacteria. In addition, the antibiotics are passed to us through the food chain. Less intensive farming, as used on organic farms, means reduced disease and requirement for antibiotics (and they are not permitted to be routinely used as a preventative)
Some ideas for switching to organic produce:
- Some discount supermarkets now have a good organic section and / or frequently have special offers eg 3 for 2 offers on organic vegetables, in which case bulk buy, cook and freeze
- Frozen organic vegetables are ok and may be a cheaper option
- Make meat go further eg organic whole chicken can be roasted and the bones used to make a stock (slow cook for 24 hours). Use the stock to cook vegetables and rice and add the leftover meat
- Choose organic meat as much as possible and eat less meat – reduce portion sizes and have some meat-free days. Organic eggs can be used as the basis for an economical meal
- Choose organic varieties of fruit and veg that tend to get heavily sprayed and that have been found to be more heavily contaminated with pesticides. The US Environmental Working Group have identified foods that tend to be heavily sprayed and contaminated with pesticide residues – these are referred to as the ‘Dirty Dozen’. In contrast, the ‘Clean Fifteen’ have been found to have less pesticide contamination. These lists are based on US produce and so may be different in the UK but are nevertheless a useful starting point https://www.ewg.org/foodnews/#.WZVkNbpFyUk
- With regard to fish, organic farmed is preferable to conventionally farmed, but best is ‘wild’ fish eg wild salmon. Frozen wild salmon fillets are a good value option, or fish that are naturally sourced from the wild eg sardines (if tinned then choose in olive oil)
Toxins are present in food grown organically and conventionally due to environmental contamination. However, there is an increasing body of evidence that organic food has increased levels of some nutrients and lower levels of toxins. Organic food is therefore highly recommended in any diet but especially for those suffering from chronic diseases where there is an urgent need to reduce toxic load and maximise nutrient intake.
It is beyond the scope of this blog to discuss the animal welfare and environmental impacts of conventional versus organic farming but these are other considerations and more information is available on the Soil Association website.
- Organic vegetables have higher levels of antioxidants. Some vitamins eg vitamin C and minerals eg iron and zinc may also be higher in some produce
- Dairy and meat from organically-reared animals has a higher proportion of omega-3 essential fatty acids
- Levels of pesticides are lower in organic produce. For example, the pesticide glyphosate, a carcinogen, has been found in 60% of wholemeal bread samples tested. On average, pesticide residues are 4x high in conventionally farmed produce compared to organic
- In particular, there is concern about the effect of pesticides on children and during pregnancy
- Cadmium levels are 50% lower in organic produce
- Antibiotics are routinely used in some conventionally-reared animals and this is contributing to antibiotic resistance and residues remain in the final product and so are passed on to us
If you have any questions regarding the topics that have been raised, or any other health matters please do contact me (Clare) by phone or email at any time.
email@example.com, 01684 310099
Clare Daley and the Cytoplan Editorial Team
Cytoplan Soil Association Certified Products:
Nutri Fruiti – This multivitamin and mineral supplement comprises a plethora of organic wholefood vitamins and minerals and contains a blend of edible plants such as amla, guava and lemon fruits.
Organic Women’s Wholefood Multi – 100% certified organic blend of edible plants. This supplement includes magnesium, iron, vitamin C, vitamin E plus many more.
Organic Vitamin C – Cytoplan’s Organic Vitamin C provides 200mg (per capsule) of natural vitamin C which is derived from organic amla fruit.
Organic B Complex – The Organic B Vitamins Complex contains good levels of B vitamins, including thiamin (B1) riboflavin (B2) niacin (B3) pantothenic acid (B5), vitamin B6 and folate.
Organic Garlic – This supplement provides 400 mg of organic garlic powder.
Organic Spirulina – Organic Spirulina contains pure spirulina platensis, vitamins, minerals, essential and non-essential amino acids, fatty acids, trace elements and the carotenoids beta carotene, beta cryptoxanthin and zeaxanthin.
Organic Kelp – Our kelp supplement contains 3 species of wild bladderwrack seaweed.
Organic Ashwagandha – Organic Ashwagandha comes at a potency of 500mg per capsule.
Organic Bacopa Monnieri – Organic Bacopa Monnieri is a herbal product at a potency of 500mg per capsule.
Organic Curcumin Plus – Organic Curcumin Plus is a herbal complex containing turmeric (providing curcumin), cat’s claw and gotu kola.
Organic Gotu Kola Plus – Organic Gotu Kola Plus is a herbal complex containing gotu kola, shankhpushpi, amalaki fruit, bibhitaki fruit and haritaki fruit.
Organic Flax Oil – This supplement comprises 500 ml of cold pressed organic flaxseed oil. The fresh oil of the flax seed is an omega-3 edible oil, containing on average 55% linolenic acid.
Alliance to Save our Antibiotics (2014) – https://www.sustainweb.org/publications/antimicrobial_resistance/
Baranski M 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, 794-811
European Parliament (2016) – Human Health Implications of Organic Food and Organic Agriculture. Report. http://www.europarl.europa.eu/RegData/etudes/STUD/2016/581922/EPRS_STU(2016)581922_EN.pdf
FiBL (2006) – Quality and Safety of Organic Products. 1st Edition, dossier
Hoffman J R & Falvo M J (2004) – Protein – which is best? Journal of Sports Science and Medicine. Vol 3: 118-130
Kuepper G & Gegner L (2004) – Organic Crop Production Overview. ATTRA.
Soil Association (2001) – Organic Farming Food Quality and Human Health, A Review of the Evidence.
Soil Association (Undated) – Policy Document – Pesticides in your food
Srednicka-Tober D et al (2016) – Composition differences between organic and conventional meat: a systematic literature review and meta-analysis. British Journal of Nutrition, 115, 994-1011
Stanner S (2001) – Putting the Pesticide Panic into Perspective. Nutrition Bulletin. Vol 26: 7-8
The Sunday Times (28 October 2007) – Eat your words, all who scoff at organic food. News. Page 11