People often perceive food that is labeled “organic” to be healthier, more “natural,” and better for the environment than conventionally grown food. This month, we’ll take a look at the myths and realities behind that image.

There’s no doubt that the “organic” label is a valuable one. Many of us are prepared to pay more for food we believe has been grown without artificial chemicals—a 2015 consumer report claims that on average organic foods are 47 percent more expensive than their nonorganic counterparts (although there’s a lot of variation for individual products).

But what does “organic” actually mean, and should we care?

The exact standards that a food needs to meet in order to use the “organic” label vary from country to country, but in general the stated aim of organic farming is to "integrate cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity." In practice, that means that organic food should be produced without synthetic pesticides and chemical fertilizers (although certain “approved” pesticides may be used).

This is a tricky question, and it doesn’t have a straightforward answer. In this article, we’re going to stick to organic fruit and vegetables—adding in meat and dairy would make things even more complicated!

We’ll start by looking at the possible health benefits of organic produce.

Is organic food more nutritious?

There have been several reviews of the scientific literature that looked at the nutritional content of organically grown food compared to conventional produce, and these have reached different conclusions.

A review in 2009 of 67 studies couldn’t find much difference in nutrient quality between organic and non-organic food, and a larger systematic review in 2012 of 237 different studies concluded that “the published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods.”

A 2014 review in the British Journal of Nutrition did find that certain organic fruits and vegetables did contain higher levels of antioxidants, as well as lower levels of cadmium (a toxic heavy metal). There’s no evidence to show that either of these things is associated with any particular health benefit to people eating organic food, though. (We’ll cover the health benefits of antioxidants thoroughly in next month’s column.)

Part of the problem here is that there are a lot of variables to take into account when it comes to farming. Whether a carrot has been grown organically or not, its nutritional content will also depend on factors such as the quality of the soil, weather conditions, how long it has been stored, the conditions it’s been stored in, and may other details. These are things that we’re often not aware of when we pick our vegetables off the supermarket shelf.

How about pesticide residues?

Pesticide residues have been found to be lower in organic food compared to conventionally grown food.

That’s a good thing, right? Well, maybe. Advocates of organic food point out that many pesticides and herbicides used in conventional agriculture are toxic. This is true—if you drink a can of it, you’ll be in trouble. Farm workers, and others who are exposed to high levels of pesticides do suffer from higher rates of certain cancers, Parkinson’s disease, and other health problems. But the devil is in the detail. Many things that are toxic in large quantities are relatively harmless in lower doses—take vitamin C, for example. So, are the pesticides in common use today likely to cause us health problems in the concentrations they’re typically found in? This is where things get difficult.

Tolerance levels for “acceptable” levels of pesticides that remain on food are established by organizations such as the U.S. Environmental Protection Agency. These are based on the results of toxicological studies, but in many cases the long term effects of low levels of pesticide exposure in humans are not thoroughly understood—for the obvious reason that it would be unethical to do the kind of trials needed. There are certainly cases of pesticides being withdrawn from use after they turned out to be more harmful than originally thought—for example, the infamous DDT. While there isn’t much evidence to suggest that the chemicals used in agriculture are likely to be harmful in the quantities typically ingested, some people take the quite reasonable position that we don’t know enough to say for certain they’re not, either.

Organic agriculture isn’t completely free from chemicals either, though. “Natural pesticides” that are approved for organic use are not necessarily any safer than synthetic pesticides. It’s a fallacy to assume that just because a chemical is “natural” it must be safe, or better for your health than an artificial substance. There are plenty of natural poisons that you definitely wouldn’t want added to your food. In addition, some of the regulations that apply to synthetic pesticides and herbicides don’t apply to “natural” alternatives, so these chemicals have often not been tested as thoroughly.

So, is organic food better for your health or not?

There’s remarkably little direct evidence either way. The 2012 review that we mentioned earlier only had 17 studies that looked at the effects of eating organic food on human subjects, and none of those followed people for longer than two years. Those studies found no significant differences in health outcomes between populations consuming organic versus conventional food, but it’s possible that effects might take longer to show up. Real world studies looking at how diet affects health tend to be problematic for other reasons, too. There are a lot of different variables involved and getting people to stick to a particular dietary intervention is notoriously difficult. This means that there’s a whole lot we simply don’t know.

What about the environment?

Organic farms release fewer synthetic chemicals into the environment; but in the same way that the “natural” pesticides used in organic agriculture may not be better for your health than their synthetic counterparts, we also can’t be sure that they’re better for local wildlife. In a few cases there’s evidence suggesting that they may actually be worse.

Organic farms also produce lower yields than conventional farms. This means that more land is needed to grow the same amount of food. On a small scale, that’s not necessarily a huge problem, but if more people were to buy organic food, it would increase the amount of land needed—which could in itself be destructive.

On the other hand, some organic farming methods have been shown to be better for local environments than their conventional counterparts. For example, methods such as crop rotations and companion planting (where complementary crops are planted together) are beneficial for both the soil and the environment.

Becoming “certified” as an organic farm means jumping through the right hoops. There are some small, local farms that use predominantly ecologically friendly farming methods but don’t meet the criteria for organic certification because they use a small amount of conventional pesticides or herbicides; equally there are large “organic” farms which operate in many respects more like a conventional factory farm, but tick the boxes and collect a premium price for their produce.

Overall, environmental impact is a devilishly hard thing to assess. There are so many different factors involved, that putting the emphasis solely on one thing (the chemicals used, for example) means that other important considerations can get missed.

The verdict: uncertain. False in some respects, but may be true in others.

If you want to improve your nutrition and health, you’re probably better off just eating more fruit and vegetables, instead of worrying about whether they’re organic. Most of us could benefit from eating more unprocessed plants, and in that respect, the higher price tag associated with organic produce may be counterproductive.

If you can afford it, then buying organic produce may help to reduce your exposure to synthetic pesticides—but there’s no guarantee that the natural products used by organic farms are any better for you. It’s unlikely to make you healthier in the short term, and we simply don’t know about the long term.

If your concern is with the environmental issues, then you’ll want to find out a bit more about the farm that you’re getting your produce from, rather than just opting for the “organic” label on your next trip to the supermarket. A local organic farm shop or a farm-to-door delivery service that works with regional farms in your area might be a good way of going about this. In addition to any benefits from organic farming, you’ll also be supporting local farmers and reducing the number of “food miles” your dinner has to travel to get to you.