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Food blogs, celebrities, and nutritionists all advocate the benefits of eating organic (有机的) fruits and vegetables. But a new study published in Science Advances paints a more complex picture. While organic produce is likely slightly healthier to eat and, in some ways, more sustainable to grow, there are also downsides.

Organic fruits and vegetables typically cost more than conventional ones. To get a certificate as organic, farmers must meet specific criteria, including growing produce without the use of genetic engineering and chemical inputs. Without these methods, the growing process typically requires more labor, time, and money, a cost that is passed down to consumers.

It’s true that in many ways, organic is more sustainable than conventional farming. But when it comes to environmental concerns such as greenhouse gas output and water loss, the comparison gets complex. Organic farms produce less greenhouse gas output per acre. However, because they are barred from using genetic engineering, pesticides (杀虫剂), and other methods that increase efficiency (效率), organic farms also produce an estimated 19% to 25% less yield than conventional farms. While there isn’t a whole lot research on the topic, the few studies that do exist suggest green gas output and water loss might actually be higher on organic farms, on a per unit basis, says study author Verena Seurfert.

In addition, while organic produce is likely more nutritious than conventional fruit and vegetables, there’s not a lot of evidence to support the claim that these often slight differences influence consumer health. The same is true for pesticide remainder. In developed countries, where pesticide use is tightly regulated, there’s no scientific consensus on how these often slight differences influence human health.

Still, Seurfert stresses that if you can afford to eat organic, you should do so. Organic farms provide safer work environments for workers, plus they support great biodiversity. The real takeaway from her study is not that organic is bad but that the practice needs more studies to increase yield without lowering sustainability.

But if you can’t afford to buy organic produce, don’t stress too much, particularly from a nutritional perspective.