Organic foods protect against cancer?


Who eats organic, thinking, presumably, to the environment. But what if organic food is also of one’s own health? French researchers report that those Who consume more organic products, tissue a lower risk for cancer, specifically for breast cancer and lymphoma, so tumors in the lymph.

That sounds like a further reason to strengthen the organic farming and to rethink his own eating habits. But the thing is so simple? Unfortunately not.

“It is difficult to investigate the influence of diet on the development of cancer, simply because the diet is so difficult to measure,” says Tilman Kühn from the German cancer research center (DKFZ) in Heidelberg.

The French scientist Julia Baudry of the University of Paris tried it in the following way: they evaluated data from a large-scale study which seeks to investigate the relationship between diet and health, the NutriNet-Santé study. The participants stated, for example, how often do you fruit, vegetables, fish and meat, eggs, bread, and chocolate as a Bio-variant consumed. The researchers information of 68.946 adults were overall. In the current study, the women take part in most of all, they make nearly 80 percent of the participants.

The risk of cancer decreased, the more organic food the study participants ate

In the following years, with an average of the scientists had observed the participants in four and a half years – reported by 1340 people, almost two percent of the subjects, of a new cancer disease. Most often it came to breast cancer (459 cases), followed by prostate cancer (180 cases), skin cancer (135 cases), colorectal carcinoma (99 cases) and Non-Hodgkin’s lymphomas (47 cases) and other lymphomas (15 cases).

In order to capture the context of organic food and cancer, researchers divided the participants into four groups – from lowest consumption of organic products the largest, as they report in the journal “Jama Internal Medicine”.

These groups differed in many ways. People who ate a lot of organic products,

  • drove in sports,
  • were more often non-smokers,
  • had a higher household income,
  • were more often married,
  • had a lower Body Mass Index,
  • were older,
  • drank less alcohol
  • and ate less red meat.

In the following analysis, the researchers pulled these differences into account, because some of these habits also have an impact on the risk of cancer.

The analysis revealed that those participants who had particularly consumed frequently organic food, had a lower risk of breast cancer after the Menopause, as well as for lymphomas. The risk of cancer was food, therefore, in the case of participants with the highest organic food consumption by 25 percent, or 0.6 percentage points lower than participants with the lowest consumption of organic. But this is no proof that organic food lowers the risk of cancer. The can’t deliver a study of this type, you can only reveal possible links and notes deliver.

But: “The found a statistical connection is convincing enough, in order to explore this topic further,” says Kühn from the DKFZ. The study alone will deliver, but no convincing evidence, in order to cancer prevention on organic food.

A 2014 published study in the UK, with around 623.000 women, was also collected, in what quantity, participants of organic products ate and how many of them became ill with cancer, came to this conclusion: Although the risk for Non-Hodgkin lymphoma fell with increasing organic consumption. However, the risk for breast cancer did not fall but even increased slightly. Why the study distinguished results at this critical point, is unclear.

Less use of pesticides as a possible cause

The researchers explain the protective effect, especially with the lower content of pesticides in organic foods. That sounds first of all, inconclusive: Some pesticides are suspected to increase the risk of cancer. Organic food have studies suggest that less pesticide residues than conventionally produced foods because in Organic farming the use of these resources is largely prohibited.

“The reduction of the lymphoma would be with this pesticide hypothesis, in principle, to be consistent,” says Heiner Boeing from the German Institute for nutrition in Potsdam-Rehbrücke (DIfE). For breast cancer nutrition researcher holds a connection because of the hormone-like effect of some pesticides are, in principle, plausible.

But: Was the pesticide load in the Bio-Fans among the participants is actually lower? “For this, the researchers provide no empirical evidence”, writes a team of researchers led by Frank Hu of Harvard University in Boston, USA, in a comment on the study.

“Actually, the researchers would have to measure the pesticide load in the blood, then the context would be unique,” says Kühn from the DKFZ. “So the possibility that other factors, such as a General healthier life style, for the observed effect is responsible – even when the researchers adjusted for important known risk factors, such as the Smoking behavior.”

The limit values for pesticides are too high?

Add to that: Even in the case of conventional foods pesticide residues in Germany and the EU are in most cases within the specified limits. The recent report by the European food safety authority (Efsa), according to more than half of the nearly 85,000 in the year 2016 sample was stands like a tested food completely free of pesticide residues, more than 96 percent were within the limits. The Federal office for consumer protection and food logs for 2016, and 1.7 percent of the samples from Germany Exceedances of the pesticide residues.

The results of the French researcher can, theoretically, mean that the limits that are considered safe are really safe and they need to be reassessed, says nutritionists Boeing. This conclusion was surely premature, as long as the in the study found the protection of organic food can not be with a simultaneous measurement of pesticide residues in blood or urine.


Who paid for it?

The NutriNet-Santé study, whose data the researchers used, is paid for by various public Authorities in France and the University of Paris. For the current evaluation Julia Baudry received a state support in the framework of a programme to promote the development of sustainable food production.


More research in this area is urgently needed, because food would be consumed and spread with pesticide residues, writes the Team led by Frank Hu in his comment.

Meanwhile, scientific studies provide just a few food suggestions that you can affect the risk of cancer. “The frequent consumption of red meat such as beef or pork, is associated with an increased risk of colorectal cancer, a high fiber content in the diet from whole grain products seems to protect against that, however,” explains Kühn.

How the cancer risk is actually lower

Off of individual foods or food groups in the field of nutrition is a preventable risk factor, the evidence influencing the risk of cancer, says Boldly: being Overweight. “About 6 to 7 percent of the cancer cases to obesity.” The impact on various cancer types detected.

Who would like to affect the risk of cancer with the diet, should avoid the light of current scientific knowledge, first and foremost, being Overweight or fight. Over 30,000 cases of cancer are likely to be due to information from the German cancer research center in the year 2018 on too much weight. A total of 165,000 cases of cancer in Germany is preventable, by quitting Smoking, healthier eating or more physical activity, for example.

The Change to organic food is likely to be one – if at all – rather subordinate role to play, says DKFZ-researchers Boldly. “There are many good reasons to buy organic food and eat. But to reduce the risk of cancer about it – which I think is currently still insufficient proven.”

Summarized: According to a recent French study decreases the risk for breast cancer and lymphomas in increasing consumption of organic food. As long as the result has yet to be proven with further studies, but it is premature to recommend organic food as a cancer preventative.