Organic MEAT Quality
Source Information: Średnicka-Tober et al. (2016) Composition differences between organic and conventional meat; a systematic literature review and meta-analysis. British Journal of Nutrition. 115, 994-1011.
New study finds significant differences between organic and non-organic MEAT
In the largest study of its kind, an international team of experts led by Newcastle University, UK, reports that organic meat contains 47% more omega-3 fatty acids, but significantly lower concentrations of the undesirable saturated fatty acids myristic acid and palmitic acid.
The study, published in the British Journal of Nutrition also reports that organic meat has significantly higher levels of polyunsaturated fat (PUFA) and omega-6 fatty acids, but lower concentrations of mono-unsaturated fatty acids (MUFA) and a lower omega-6/omega-3 fat ratio. In addition, analysis detected trends towards higher iron (Fe) levels, and lower concentrations of copper (Cu) and the toxic metal cadmium (Cd) in organic meat.
Newcastle University’s Professor Carlo Leifert, who led the study comments: "Meat is an important source of omega-3 in our diet, especially for individuals who consume little or no fish. Switching to grass-fed organic meat may allow meat consumption to be reduced by around 30% without a reduction in total omega-3 fatty acid intake."
New Methods used to analyse the data
This is the first extensive review of the nutrient content in organic vs conventionally produced meat and used state-of-the-art meta-analysis methods. The paper also reviews evidence from controlled scientific studies which indicate that outdoor grazing/foraging-based production methods and high forage/low concentrate based diets were the main reason for composition differences between organic and conventional meat.
The findings contradict those of a UK Food Standard Agency (FSA) commissioned study which concluded there were no substantial differences between organic and non-organic livestock products, although this was based on less than 20 comparative studies on meat and combined data from meat and milk composition.
Interestingly, the authors, Dangour et al. reported a trends towards significantly higher levels of polyunsaturated and omega-3 fatty acids in organic livestock products (meat and milk) in their report to the FSA (Dangour et al. 2009b), but not in the paper and press release they published.
What the findings mean
A range of polyunsaturated fatty acids, in particular omega-3 fatty acids, have been linked to a decreased risk in cardiovascular disease. In contrast, the saturated fatty acids myristic acid and palmitic acid have been linked to an increased risk of cardiovascular disease.
The thrombogenicity index (an index calculated from the relative concentrations of fatty acids linked to an increase or decrease in cardiovascular disease risks) was found to be lower for organic meat, indicating a lower risk compared with conventional meat.
Prof Chris Seal from the Human Nutrition Research Centre (HNRC) at Newcastle University comments: "Omega-3s are linked to reductions in cardiovascular disease, improved neurological development and function, and better immune ability."
"Western European diets are recognised as being too low in these fatty acids and the European Food Safety Authority (EFSA) recommends we should double our intake."
"But getting enough in our diet is difficult. Our study suggests that switching to organic would go some way towards improving intakes of these important nutrients."
Prof Leifert comments: "Given that it is difficult to implement current recommendations to increase omega-3 intakes with increased consumption of oily fish, a switch to grass-fed meat from organic or other low-input grazing based systems may be an important alternative."
New information on health benefits
Compared to systematic reviews/meta-analysis on crops and milk/dairy products carried out by the Newcastle-led team, the evidence base for comparing composition differences between organic and conventional meat is much smaller; only 67 papers providing data on beef, lamb, goat, chicken and/or rabbit meat were available.
It was therefore not possible to accurately compare the composition of specific meat types (e.g. beef, lamb, goat, pork and poultry meat). Also, for most parameters, there was low statistical power and reliability.
Also different to crops and dairy based foods, there are currently no published cohort studies linking organic meat consumption to beneficial impacts on human health.
Gillian Butler, co-author and senior lecturer in animal nutrition at Newcastle University, explains: "Further studies are required to enable meta-analysis for a wider range of nutrients (e.g. antioxidants, vitamin and mineral concentrations) and to improve both precision and consistency of results for fatty acid profiles for meat from all (livestock) species."
Professor Leifert added: "We have shown without doubt there are composition differences between organic and conventional meat. There is an urgent need to address the limitations identified in the evidence we have and carry out well-controlled human dietary intervention and cohort studies that are specifically designed to identify and quantify the health impacts of switching to organic meat consumption."
Professor Carlo Leifert, Professor of Ecological Agriculture, School of Agriculture, Food and Rural Development, Newcastle University. Tel: 01661-830222/830444; E-mail: firstname.lastname@example.org
Louella Houldcroft, Senior Communications Manager, Faculty of Science, Agriculture and Engineering, Newcastle University; Tel: +44 (0) 191 208 5108; Mob: 07989 850511; Email: email@example.com