Post by Allison Aubrey, The Salt at NPR Food (2/20/13)
A new study published in the journal PLOS ONE finds that tomatoes grown on organic farms were about 40 percent smaller than conventionally grown tomatoes. The upside? They pack more of a nutritional punch. The researchers found the organic tomatoes had significantly higher levels of vitamin C, sugar and lycopene.
Now, while the extra sugar may improve the taste, it's the lycopene that could amp up organic tomatoes' health profile. Lycopene — a compound that gives tomatoes their red coloring — has been linked to a decreased risk of stroke in people who consume a lot of it.
So what explains the increase in healthy compounds in the organic fruit?
Well, researchers say the organic system of agriculture tends to "stress out" the tomato plants. For instance, when tomato plants fend off pests without the use of heavy-duty pesticides, they produce more stress compounds — such as vitamin C and lycopene — to defend themselves. It's similar to the way we humans make antibodies to fight off a disease.