First of all, I want to get one message across: any type of vegetable or fruit, whether conventional or organic, is better than none.
Now, before we jump into what how organic and conventional produce affect our health, I think it’s important to understand what the fundamental differences between organic and non-organic farming are. In order to understand what ‘organic farming’ means, I have reviewed the definitions and guidelines supplied by USDA NOP (US Organic certifying body ‘National Organic Program’), Soil Association (UK Organic certifying body), ACO (Australian Certifying body), Eco Cert (European certification) and then summarised them at a high level in the below diagram. (1,2,3,4)
So now that we understand what differentiates organic versus conventional farming, the question is: is organic really worth the extra cost? Here, the science is slightly conflicting. One one hand, a study published in the British Journal of Nutrition appears to show a significant difference in the nutritional content of organic versus non-organic fruits and vegetables (5). This study reviewed 343 peer-reviewed publications and concluded:
In conclusion, organic crops, on average, have higher concentrations of antioxidants, lower concentrations of Cd (toxic metal) and a lower incidence of pesticide residues than the non-organic comparators across regions and production seasons.
The theory behind the higher antioxidant levels in the organic produce found in the above review was that organic fruits and vegetables have to fend for themselves to protect themselves from pests, and in so doing, they produce more phytonutrient antioxidants. Taking a step further, science shows that these antioxidants are particularly helpful in reducing free radical damage and reducing the chances of developing many chronic illnesses when incorporated in the human diet.
However, the study’s findings are in stark contrast to a 2012 Systematic Review performed by a group of researchers at Stanford University, which found no difference in the nutrients when it conducted a review on 240 studies (6). They did, however, make comment about pesticides and bacteria in their conclusion:
The published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods. Consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.
The bottom line is that the macronutrients between Organic and Conventional produce are not dissimilar. At a micronutrient level, there appears to be conflicting findings, however the strongest paper without any conflict of interest reports no significant nutrient differences between organic and non-organic fruits and vegetables. This means they found no significant difference in calories, carbohydrates, fibre, sugars, protein or vitamins/minerals, etc.
However, given conventional farming can use any number of over 300 permitted artificial pesticides, it is highly probable that in consuming non-organic (conventional) produce you are exposing your body to artificial pesticides, herbicides and fertilisers which you would otherwise be avoiding if you were consuming organic produce. Are these at a level that will effect your health? There’s no evidence to suggest that the artificial pesticide levels are harmful (they fall within ‘safe limits’), but I wouldn’t recommend being the study cohort to test this over the coming decades. We can certainly learn a lot by looking at areas of the world that have the highest number of centurions and highest quality of life: The Okinawan’s (7).
Okinawans have less cancer, heart disease and dementia than western populations, and women there live longer than any women on the planet. Coincidentally, they do gardening well up into their 100’s, plant medical gardens, eat a largely plant-based diet and consume organic fruit and vegetables free from any artificial pesticides/residues. Of course, there are no doubt other aspects of their peaceful lives that contribute to their longevity (sense of purpose, close family connections, etc.) but this is certainly a very relevant lifestyle factor worth considering.
So for these reasons my preferred option is organic, despite not an overwhelming amount of evidence in support of them from a true nutritional point of view…yet! In saying that, I am a big believer that non-organic produce is still better than not consuming fruits/vegetables at all! So in other words, if you cannot afford organic produce or access it in your area then do not shy away from standard produce.
If budget is an issue and you can only buy some organic produce, here is a list of the best plants to source as organic. These are the plants that typically have the highest concentrations of pesticides if farmed conventionally:
A 10% salt water solution has also been shown to be effective in reducing the levels of pesticide residues on non-organic produce. (8)
Detergents or retail fruit and vegetable washes seem to make no real difference beyond what a 30 second rinse under tap water achieves (9).
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