Organic but healthier than conventional products?
According to new study, organic foods contain more antioxidants
Organic foods contain more valuable antioxidants and about half as much of the heavy metal cadmium than conventionally grown foods. In addition, fewer pesticide residues have been detected in organically produced foods. This is the result of the largest comparative metastudy to date. But the researchers have also been criticised.
A debate has been going on for decades about whether organic is better than conventional. Now there are new research results, which do not end the controversy however for a long time. An international team of researchers has evaluated 343 publications from scientific journals and thus provided the most comprehensive meta-study on the subject to date. The conclusion: There are significant differences in important ingredients and bio performs much better.
More good, less bad
There are many different organic labels. All have their own standards. In 2001, the German state organic label was introduced. There are currently 4,376 companies using the organic seal on 68,572 products as of 30 June 2014. Source: BLEThere are many different organic labels. All are based on their own standards. In 2001, the German state organic seal was introduced. There are currently 4,376 companies using the organic seal on 68,572 products as of 30 June 2014.
Source: According to the study, organically produced crops have a higher content of certain secondary plant substances with antioxidant effects Antioxidants such as polyphenols. For example, 19 percent more phenolic acids, 51 percent more anthocyanins and even 69 percent more flavanones were found.
The study also shows that organically grown foods contain on average almost 50 percent less cadmium than conventionally grown foods. Cadmium is toxic to humans. It accumulates in the body, especially in the liver and kidneys, and even small amounts can cause damage to these organs. Cancer is also associated with the heavy metal.
We mainly ingest cadmium with our food. That is why the European Commission has set maximum levels for cadmium in foodstuffs. The European Food Safety Authority (EFSA) set a tolerable weekly intake of 2.5 micrograms per kilogram body weight of 2.5 µg/kg.
In addition, the metastudy found that pesticide residues were found four times more frequently in conventional crops than in organic crops.
The differences found may be due to different cultivation practices. In organic farming, for example, chemical pesticides and mineral fertilizers must be avoided.
There are controversial results
The study was not the first to compare the nutrient content of organic and conventional foods. In 2009, the UK Food Standards Agency (FSA) commissioned a study that found no significant differences in the ingredients or additional health benefits of organic food, Dangour et al., 2009. A metastudy published in 2012 in the journal “Annals of Internal Medicine” also found no evidence of an advantage of organic food.
The current study draws on a much larger database, the scientists of the current study explain their deviating results. In the meantime, there would be many more studies on the subject that could be included in the meta-analysis.
Are organic foods healthier?
The researchers propagate that a “change to a diet with organic fruits, vegetables and cereals would provide as many additional antioxidants as one to two additional servings of fruits and vegetables daily”. However, even after this study, some experts doubt whether organic foods are significantly healthier than conventionally produced foods.
The scientist Alan Dangour (first author of the FSA study mentioned above) told the journal “Nature” that he did not see any significant differences in nutrient content. He also noted that the study included many studies of different quality, which distorted the validity of the new metastudy.
Organic farming is a particularly natural, environmentally friendly and resource-saving form of agriculture. The use of chemical pesticides or mineral fertilizers is prohibited. In addition, the soil is not ploughed.
In general, antioxidants are said to have a health-promoting effect. They are supposed to prevent cardiovascular diseases and possibly even protect against cancer. But only certain antioxidant substances had increased values in the study. Other also important antioxidants showed no significant differences. The researchers also found lower levels of proteins and amino acids in organically produced foods. This can be explained by lower nitrogen levels. Also the study could find no significant differences with most mineral materials.
“We have shown beyond doubt that organically and conventionally grown crops differ in their nutritional composition. There is now an urgent need for well-monitored human nutritional studies to identify and quantify the potential health effects of organic food,” says Carlo Leifert, Professor of Organic Agriculture at the University of Newcastle.
Nutritional studies could provide information on the health effects of eating habits (organic/conventional). However, it should be borne in mind that lifestyle, e.g. whether or not a lot of sport is done, also contributes significantly to health and must be taken into account in studies dealing with the health effects of food.
Production of organic food
When shopping, you can recognise organic food by the “Bio” or “Öko” label, the EU organic logo and the hexagonal German organic seal on the packaging. But what makes a loaf of bread organic or a cheese organic? This is precisely prescribed in the EU legislation for organic farming.
It states, among other things, that all ingredients that come from agriculture, such as cereals, milk, meat, fruit, herbs or vegetables, must come from organic farming in the production of organic food. EU legislation on organic farming also lays down how organic farmers must produce these agricultural raw materials. For example, organic farmers have to keep their animals in a species-appropriate manner and are not allowed to use chemical pesticides.
If organic milk is processed into organic cheese, organic meat into organic sausage or organic cereals into organic bread, only a few additives are permitted under EU legislation. Also the irradiation of food, in order to extend their durability and the use of genetic engineering are forbidden.
Which ingredients are permitted?
Sometimes certain agricultural ingredients are not grown organically in sufficient quantities. Under certain circumstances, these ingredients may also come from conventional agriculture. And then,
- if the ingredient is only present in small amounts in the food (maximum five percent),
- and if the ingredient is included in a list in EU legislation. For example, the following ingredients are currently listed: Gooseberries, passion fruit, raspberries, Peruvian pepper, watercress, rum or gelatine. Under certain circumstances, ingredients from conventional farming other than those listed may be used, but the food manufacturer must apply for authorisation.
Genetically modified ingredients, such as many additives or auxiliary substances, as well as genetically modified enzymes or microorganisms, are not permitted in organic products.