Nutrition in organic foods versus conventionally grown foods.

Many people think that the only difference between the nutrition in organic foods and conventionally grown foods is the effect on the environment and soil, but perhaps the most important difference is the nutrient content. Proof of the nutritional superiority of organic produce has been demonstrated in numerous studies.

I will mention some of the results here:

Studies conducted on the nutritional value of organic versus conventionally grown food.
• In 1998, a review of 34 studies comparing the nutritional content of organic versus non-organic food was published in the peer-reviewed, MEDLINE-indexed journal Alternative Therapies (Volume 4, No. 1, pgs. 58-69). In this review, organic food was found to have higher protein quality in all comparisons, higher levels of vitamin C in 58% of all studies, 5-20% higher mineral levels for all but two minerals. In some cases, the mineral levels were dramatically higher in organically-grown foods-as much as three times higher in one study involving iron content.

• Organic foods may also contain more flavonoids than conventionally grown foods, according to Danish research published in the August 2003 issue of the Journal of Agricultural and Food Chemistry. In this study, 16 healthy non-smoking participants ranging in age from 21-35 years were given either a diet high in organically or conventionally grown fruits and vegetables for 22 days, after which they were switched over to the other diet for another 22 days. After both dietary trials, the researchers analyzed levels of flavonoids and other markers of antioxidant defenses in the food and in the participants' blood and urine samples. Results indicated a significantly higher content of the flavonoid quercitin in the organic produce and in the subjects' urine samples when on the organic produce diet, plus the subjects' urinary levels of another flavonoid, kaempferol, were also much higher when on the organically grown compared to the conventionally grown diet.

• A review of 41 studies comparing the nutritional value of organically to conventionally grown fruits, vegetables and grains, also indicates organic crops provide substantially more of several nutrients, including:
• 27% more vitamin C
• 21.1% more iron
• 29.3% more magnesium
• 13.6% more phosphorus
The review also found that while 5 servings of organically grown vegetables (lettuce, spinach, carrots, potatoes and cabbage) provided the daily recommended intake of vitamin C for men and women, their conventionally grown counterparts did not. Plus, organically grown foods contained 15.1% less nitrates than conventionally grown foods. Nitrates, a major constituent of chemical fertilizers, bind to hemoglobin and, particularly in infants, can significantly reduce the body's ability to carry oxygen.

• An article published in "Coronary and Diabetic Care in the UK 2004" by the Association of Primary Care Groups and Trusts (UK). It was written by James Cleeton, Policy Projects Co-ordinator at the Soil Association.

The article concluded that a predominantly organic diet:

- reduces the amount of toxic chemicals ingested;

- totally avoids GMOs [genetically modified organisms];

- reduces the amount of food additives and colourings;

- increases the amount of beneficial vitamins, minerals, EFAs [essential fatty acids] and antioxidants consumed;

- appears to have the potential to lower the incidence of common conditions such as cancer, coronary heart disease, allergies and hyperactivity in children.


UK and US government statistics indicate that levels of trace minerals in fruit and vegetables fell by up to 76% between 1940 and 1991. In contrast there is growing evidence that organic fruit and vegetables generally contain more nutrients than non-organic food.

The Soil Association conducted a systematic review of the evidence comparing the vitamin and mineral content of organic and conventionally grown food. It was found that, on average, organic food contains higher levels of vitamin C and essential minerals such as calcium, magnesium, iron and chromium.

An independent review of the evidence found that organic crops had significantly higher levels of all 21 nutrients analysed compared with conventional produce including vitamin C (27% more), magnesium (29% more), iron (21% more) and phosphorous (14% more). Organic spinach, lettuce, cabbage and potatoes showed particularly high levels of minerals.


A high antioxidant intake has been shown to be associated with a reduced incidence of coronary heart disease and some cancers. Such antioxidants include certain vitamins (vitamin E and beta-carotene) and substances known as phenolics. Researchers have recognised the growing concern that levels of some phenolics may be lower than is optimal for human health in conventionally grown foods. Phenolics are generated by a plant when attacked by pests.

Generally, organic crops are not protected by pesticides and research has shown that organically produced fruit contains higher levels of phenolic compounds than conventionally grown fruit. Danish researchers have found that organic crops contain 10% to 50% more antioxidants than conventional crops.

• In another study whose findings are based on pesticide residue data collected by the U.S. Department of Agriculture, organic fruits and vegetables were shown to have only a third as many pesticide residues as their conventionally grown counterparts. Study data, which covered more than 94,000 food samples from more than 20 crops, showed 73% of conventionally grown foods sampled had residue from at least one pesticide, while only 23% of organically grown samples had any residues. When residues of persistent, long-banned organochlorine insecticides such as DDT were excluded from the analysis, organic samples with residues dropped from 23 to 13%. In contrast, more than 90% of USDA's samples of conventionally grown apples, peaches, pears, strawberries and celery had residues.

Organically grown food is your best way of reducing exposure to toxins used in conventional agricultural practices. These toxins include not only pesticides, many of which have been federally classified as potential cancer-causing agents, but also heavy metals such as lead and mercury, and solvents like benzene and toluene. Minimizing exposure to these toxins is of major benefit to your health. Heavy metals damage nerve function, contributing to diseases such as multiple sclerosis and lowering IQ, and also block hemoglobin production, causing anemia. Solvents damage white cells, lowering the immune system's ability to resist infections. In addition to significantly lessening your exposure to these health-robbing substances, organically grown foods have been shown to contain substantially higher levels of nutrients such as protein, vitamin C and many minerals.

Conventionally grown food and its effects on children The negative health effects of conventionally grown foods are not just limited to adults. In fact, many experts feel that organic foods may be of paramount importance in safeguarding the health of our children.

• In two separate reports, both the Natural Resources Defense Council (1989) and the Environmental Working Group (1998) found that millions of American children are exposed to levels of pesticides through their food that surpass limits considered to be safe. Some of these pesticides are known to be neurotoxic, able to cause harm to the developing brain and nervous system. Additionally, some researchers feel that children and adolescents may be especially vulnerable to the cancer-causing effects of certain pesticides since the body is more sensitive to the impact of these materials during periods of high growth rates and breast development.

Children are especially vulnerable to the toxic effects of organophosphate pesticides because their bodies and brains are still growing. Even low body levels of organophosphate neurotoxins can contribute to developmental delays, behavioural problems, attention problems/hyperactivity, poor school performance and learning disabilities.