The research showed that infants fed organic dairy products, and whose mothers had also eaten organic dairy during pregnancy, had a 36 per cent lower incidence of eczema than those who consumed conventional dairy products.
Of course, the best health choice for an infant is not to use any dairy products other than breast milk at all, a proposition for which there is very strong evidence. Also, pregnant women are a natural place to look for health benefits, as the hypersensitivity of pregnant women to environmental factors is well established.
The study, as it is narrow, however, does not determine more broadly if there are health risks, as well as benefits, to organic food. Recent cases of food poisoning from organic spinach make clear that organic doesn't mean risk free. Fertilizers are used to encourage healthy growth in plants and pesticides are meant to prevent insects from harming plants. Insect infected plants (as a result of not using pesticides) could also pose health risks, and the fact that something is "natural" doesn't mean that it is safe. Nature is full of poisonous plants and pathogens every bit as bad as those we devise ourselves. In the same vein, "herbal" does not mean safe, it means "not proven to be safe and effective."
This doesn't mean that there aren't health benefits from eating organic, and there isn't any evidence of which I am aware that eating organic is on average less healthy than eating conventional food. There is suggestive evidence that shows that there are real differences, at a statistical level anyway, between organic and non-organic food that one can plausibly imagine might have health benefits. But, the same study makes clear that the evidence that health benefits actually result from these differences is inconclusive. Certainly, the evidence of health benefits is surprisingly slim to form a basis for what is a several decades old major agricultural industry whose marketing has been based to a great extent upon the personal health benefits of eating organic food.
On the other hand, in part, the lack of proof arises from the difficulty in proving the health benefits of something like eating organic foods and the lack of an obvious sponsor for such an expensive study. No one small organic farmer can afford that, and even associations of organic farmers tend to be small and cash strapped. Any study attempting to prove that there are health benefits from eating organic food also runs up against the usual confounding difficulties involved in any study of large populations of human subjects.
Organic dairy product use, for example, normally isn't an independent variable from other plausible lifestyle issues with important health impacts. For example, it is safe to guess that people who make an effort to buy organic produce, on average, eat more fruits and vegetables than those who do not. Likewise, in the American context, at least, an "organic lifestyle" is also correlated with affluence, access to health care, and individuals who pay attention to their own personal health and exercise regimes. In our current economy it takes more time and money to buy organic, involuntarily excluding the poor and those with little leisure time. It is, of course, uncontroversial that eating more fruits and vegetables, getting more exercise, and being able to access health care when appropriate, and for that matter, on average, affluence (which, for example, makes it less likely that you will live near a toxic chemical emitting industrial facility or in a home with lead pipes), is good for your health. Even if organic foods were actually, on average, slightly worse for you from a health perspective than conventional foods, we would expect people who follow the American version of the "organic lifestyle" to be healthier.
There are proven benefits of organic farming that do not involve personal health. Most importantly, organic farming is far less reliant upon petroleum based fertilizers, reducing the oil dependency of our economy. As oil prices rise, organic food should actually become cheaper than conventional food (of course, a century ago, almost all food was organic). Likewise, there is evidence that pesticides and fertilizers are harmful to the natural environment, and may pose health risks to farmers. But, the main solidly fact based reasons to buy organic are altruistic and environmental in nature, not personal health based.