Are Organic Foods Safer or Healthier Than Conventional Alternatives?: A Systematic Review

In the citing paper

“As a result, there is still considerable controversy as to whether the use of organic production standards results in significant and consistent changes in the concentrations of potentially health-promoting (e.g. antioxidants, (poly)phenolics, vitamins and certain minerals) and potentially harmful (e.g. Cd and Pb) compounds in crops and crop-based foods( 7 , 19 – 22 ).”

In the citing paper

“However, these systematic reviews (1) used different methodologies (e.g. weighted and unweighted meta-analyses) and inclusion criteria, (2) did not cover most of the large amount of information published in the last 4–5 years, (3) provided no structured assessment of the strength of the evidence presented, and (4) came to contrasting conclusions.”

In the citing paper

“However, there is increasing evidence and more widespread acceptance that the consumption of organic foods is likely to reduce exposure to pesticide residues( 21 , 23 , 24 ).”

In the citing paper

“Several systematic literature reviews have recently analysed the available published information, using both qualitative and quantitative methods, with the aim of identifying the potential effects of organic and conventional production protocols on the nutritional quality of crops( 19 – 21 ).”

In the citing paper

“There are, to our knowledge, only two human dietary intervention studies in which contrasting antioxidant/(poly)phenolic intake levels were generated by providing diets based on conventional and organic crops; both studies focused on assessing antioxidant status in humans and were inconclusive with respect to the identification of potential health impacts of organic food consumption( 21 , 42 , 43”

In the citing paper

“The finding of a four times higher frequency of occurrence of pesticide residues in conventional crops confirms the results of the study of Smith-Spangler et al. ( 21 ), in which a very similar set of studies (nine of the ten publications used in the present study) were used for analysis.”

In the citing paper

“However, it contradicts the results of the systematic reviews/meta-analyses by Dangour et al. ( 19 ) and Smith-Spangler et al. ( 21 ), which indicated that there are no significant composition differences between organic and conventional crops.”

In the citing paper

“This supports previous studies that have concluded that organic food consumption can reduce exposure to pesticide residues( 21 – 23 ).”

In the citing paper

“In contrast to previous literature reviews( 19 – 21 ), the larger number of studies now available allowed separate meta-analyses to be carried out for different crop types (e.g. fruits, vegetables and cereals), but only for a limited number of composition parameters.”

In the citing paper

“As has been mentioned in previous reviews( 19 – 21 ), pooling diverse information was necessary, because for most of the composition parameters, the number of published studies available was not sufficient to carry out separate meta-analyses for specific countries/regions and crop types and species.”

In the citing paper

“Similar to the results of the present study, a recent literature review by Smith-Spangler et al. ( 21 ) has also reported that of the seventy-seven comparative data sets (extracted from fifteen publications), twenty-one indicated significantly lower and only one significantly higher Cd concentrations in organic foods.”

In the citing paper

“However, they concluded that the currently available data do not allow clear trends with respect to health markers and outcomes to be identified.”

In the citing paper

“A recent review by Smith-Spangler et al. ( 21 ) has analysed the results of fourteen studies in which the effects of organic and conventional food (both crop and livestock product) consumption on clinical outcomes (e.g. allergic symptoms and Campylobacter infections) and health markers (e.g. serum lipid and vitamin concentrations) were studied.”