It’s Saturday morning and it’s time for your weekly grocery shopping. As you walk down the produce section, you are faced with a difficult decision: “Should I buy the organic apples or the regular ones?” As modern society becomes more health conscious and aware of what is being put in what we eat, organic food has become increasingly popular. Annually, $106 billion USD are spent on organic products, and farmland dedicated towards producing organic foods continues to expand. However, the decision to buy more expensive organic food remains questionable. Are organic foods healthier and do the health benefits justify the cost?

What are organic foods?

Put simply, organic food is defined as food produced in a farm that strives to imitate the products’ natural environment. Importantly, organic food and organic agriculture are heavily regulated by the USDA (in the United States) or EFSA (European Union).

For organic plant foods, such as vegetables and fruits, production methods avoid the use of most fertilizers and plant protection products, including synthetic forms of:

• Mineral fertilizers
• Pesticides 

For organic animal products, such as meat and dairy, the animals are bred and raised without antibiotics and within natural conditions:

• No use of medicines and drugs, including antibiotics and hormones, that promote growth.
• Feed must be organic and livestock must graze on pasture grown on healthy soil.

Additionally, food from both plant and animal raw materials cannot come from genetically modified organisms, be treated with radiation, or include most food additives (e.g., artificial food coloring, sodium nitrite to prevent bacterial growth, or high fructose corn syrup).

Key differences: Organic foods vs. conventional foods

Interestingly, the macronutrient content of organic foods is not significantly different from conventional counterparts. Instead, it is the presence of pesticides and additives in conventional foods, which can alter the molecular composition of these foods, that distinguishes conventional from organic foods. 

Of note, research has demonstrated that organic foods from raw plant materials contain lower of levels of potentially toxic substances:

• Several studies have demonstrated that organic foods can have between 15-50% lower levels of nitrates (a key component of fertilizer) compared to conventional foods. However, it is important to note that the results here are variable, with some studies demonstrating no significant differences in nitrate levels between organic and conventional plant raw materials. Additionally, given that average consumption of nitrates is lower than toxic levels, the effects of nitrate on human health are inconclusive.

• In a comprehensive meta-analysis of 343 peer-reviewed publications, it was concluded that organic products have lower levels of toxic metals: in particular, cadmium. That being said, other studies have demonstrated that utilization of organic fertilizers results in increased levels of lead, zinc, and nickel — while also showing decreased levels of cadmium, chromium, and copper.

• While pesticides are not permitted in organic production, analyses from the European Union revealed that 6.5% of organic products contain pesticide residues. Conventional foods exceed permissible levels of pesticides six times more often than organic foods, although the frequency is small in both types of food: 1.2% of conventional food samples vs. 0.2% of organic food samples.

Due to the lower levels of toxic substances in organic foods, they often contain higher amounts of potentially beneficial compounds:

• Some organic fruits and vegetables contain higher levels of vitamin C compared to conventional produce; however, this largely depends on location and type of produce. For example, one study found increased levels of vitamin C in organic acerola vs. conventional, while conventional strawberries had more vitamin C compared to their organic counterparts. Other studies have shown no differences in vitamin C content between conventional and organic cabbage, carrots, and lettuce, while they have found a significant increase in vitamin C when comparing organic and conventional Valencia oranges.

• Research has shown that organic foods contain higher levels of antioxidants, in particular polyphenols. However, results here can vary: one meta-analysis demonstrated that levels of phenolic compounds and phenolic acids in organic fruits were not statistically significant compared to conventional. There was, however, evidence for an increase in flavones and flavonols (classes of polyphenolic compounds) in vegetables and cereals.

• Organic dairy products have higher concentrations of omega-3 fatty acids as well as conjugated linoleic acid, iron, and ɑ-tocopherol — all of which have a variety of nutritional benefits, evidenced by scientific literature.

• Organic meat and dairy products have higher levels of unsaturated fatty acids and protein.

• Studies have demonstrated that while organic and conventional animal products do not differ in levels of bacterial pathogens, organic products typically have fewer antibiotic-resistant bacteria compared to conventional foods. 

Are organic foods healthier for you?

Organic foods are often touted as healthier than their conventional counterparts. However, the research examining the health benefits of eating organic foods has been mixed. Regardless, there have been certain studies that demonstrate the following benefits of consuming organic foods:

• In a large 2013 cohort study (54,311 adults) that examined the relationship between consumer attitude, frequency of organic product use, and overweight and obesity risk, the authors demonstrated that regular organic food consumption was associated with a marked decrease in overweight and obesity probability in both males and females.

• A 2014 study consisting of 623,080 middle aged women revealed that those who consumed organic foods had a 21% lower risk of non-Hodgkin’s lymphoma compared to those who never consumed organic food. This is complicated by a 9% higher risk of breast cancer in organic food consumers, although the authors claim this may be due to the fact that women who consume organic food are more likely to attend breast cancer screening and thus more likely to be diagnosed.

• While the study above did not show an association between organic food consumption frequency and all cancers (excluding non-Hodgkin lymphoma and breast cancer), a more recent 2018 study revealed that high frequency organic food consumption was associated with lower overall risk of cancer.

Other studies have revealed the potentially negative impacts of toxic substances (absent in organic foods), particularly synthetic pesticides and antibiotics, found in certain conventional foods: 

• In the 2013 study cited above (demonstrating the association between reduced obesity risk and organic food consumption), the authors cite a link between pesticide exposure and increased risk for obesity development. Indeed, other studies have shown that exposure to a variety of organic pollutants, including pesticides, leads to increased risk of obesity, insulin resistance, type 2 diabetes, and cardiovascular diseases.

• Although results have been mixed, due to small sample sizes, there are some reports indicating that pesticide exposure can lead to increased risk of non-Hodgkin’s lymphoma.

• More alarming results from a series of studies has revealed that children born by mothers exposed to high levels of pesticides (including those used in agriculture) exhibit marked cognitive impairment, including deterioration in perceptual reasoning, working memory, and an average 7-IQ-point deficit compared to children born by mothers with low pesticide exposure. (Fortunately, once born, children exposed to pesticides seem quite resilient to the cognitive impairment that can result from postnatal exposure.)

• Antibiotic resistance is a critical public health issue. Although antibiotics have been integral in conventional animal production, their usage in agriculture has raised concerns due to the reduction of antibiotic efficiency in human medical care. Interestingly, a 2017 meta-analysis examining both animal and human studies revealed that restriction of antibiotic use in food-producing animals is correlated with a reduction of antibiotic-resistant bacteria. While this meta-analysis found less human evidence, there are also some reports suggesting that humans, particularly farmers, exhibit a reduction in antibiotic-resistant bacteria with interventions that limit the use of antibiotics in food-producing animals. 

On the other hand, several studies have shown that the beneficial health impacts from organic food consumption are negligible: 

• A small study found no significant association between organic food consumption and the prevalence of gestational diabetes. However, regardless of whether the food was organic or conventional, lower intake of meat and cheese appeared to be correlated with lower gestational diabetes prevalence.

• A comprehensive analysis of peer-reviewed studies between 1958-2008 concluded that there is no convincing evidence concerning the nutritional benefits of organic foods.

• However, within the analysis above, one study did demonstrate that consumption of organic dairy products was associated with lower eczema risk in infants.

• In examining organic food consumption and reproductive health, a study in Danish couples demonstrated that consuming organic food had no association with pregnancy success.  

Although there have been several studies indicating that organic foods have increased levels of nutritionally beneficial compounds (such as antioxidants, omega-3 fatty acids, unsaturated fatty acids), the differences in molecular composition of organic vs. conventional foods do not appear to have a substantial impact on nutrition:

• In a 2022 study, scientists demonstrated that diet — but not food source — has the strongest impact on health. Participants maintained on a Mediterranean diet (consisting of higher fruit/vegetable and lower meat consumption) showed a large increase in total phenolic and mineral micronutrient intake — regardless of whether the diet was sourced from organic or conventional products.

• One critical variable that may confound the potential health benefits of organic foods is that individuals who tend to buy organic also tend to lead healthier lifestyles. Indeed, those who buy organic food exercise more and smoke less. 

Key takeaways

Overall, the jury is still out as to whether organic foods are healthier than their conventional counterparts. While scientists have begun to identify differences in the molecular composition of organic and conventional foods (e.g., decreased levels of toxic compounds and increased levels of antioxidants and healthy fatty acids), the potential health benefits (e.g., decreased obesity risk) require much more research before any certain conclusions can be formed. So the question remains: "Are organic foods healthier and should I spend more on that organic apple?” Perhaps the more important question is: “Am I maintaining a balanced and healthy diet of fruits, whole grains, veggies, and healthy meats?” In other words, you can go ahead and buy organic here and there when you can, but it’s the overall health of your dietary pattern that’s paramount, as well as how much you exercise and practice other healthy lifestyle habits (such as sleep hygiene and stress management).