Stress Makes Organic Fruits Healthier Than Conventional

By Lisa Raffensperger | February 25, 2013 3:43 pm

Next time you’re in the supermarket weighing the glossy conventional fruit against the small, blotched organic alternative, consider this: organic fruits’ stunted size may be the signal of their nutritional prowess.

Various studies in recent years have shown that some organic fruits and vegetables have nutritional advantages over conventionally-grown produce. For instance, organic tomatoes contain more vitamins, and organic tomato juice has more phenolics, a class of molecules that promote the body’s own antioxidant response.

But it’s been unclear exactly how organic farming brings about these changes in fruit. Now a new study indicates that the secret is stress: While conventional fruits are coddled by synthetic fertilizers, organic plants have fewer minerals available to them—and they therefore produce fruit that’s higher in human-healthy compounds.

Researchers came to this conclusion by analyzing organic and conventional tomatoes from farms in Brazil. Comparing the fruits at points throughout the growing cycle, researchers found that the conventional tomatoes were about 40 percent bigger than organics. Previous research indicates that smaller fruit is a sign that plants are under more stress. Further proof of organics’ stress came in the tomatoes’ chemistry. Organic tomatoes had higher levels of antioxidants, hinting that they were battling damaging oxidizing molecules.

These tiny organic tomatoes packed a punch: 55 percent more vitamin C and 57 percent more “soluble solids,” including sugars, which probably made them taste better too. As the researchers report in PLoS One, this is the first time organic plants’ stress has been linked to the nutritional benefits of their fruit.

The findings make sense in light of a basic principle of living things—there’s a tradeoff between growth and defense. Pampered conventional plants can direct all their energies toward growth, producing bigger fruit. But the defense activities in organic plants, which detract from growth, produce chemicals that are healthy for the human diet.

All this comes with a caveat, however. It’s not guaranteed that higher antioxidant levels in fruit translate to higher antioxidant levels in the bloodstream of those who eat it. For apples and tomato juice, at least, it appears that organics’ antioxidant benefit is lost in translation.

Top image courtesy Mau Horng / Shutterstock 

CATEGORIZED UNDER: Environment, Top Posts
  • Nullius in Verba

    That’s been well known for a long time. You also get more of this stuff when plants are under stress:

    It’s like an immune response.

  • lauklejs

    On the one hand, the 40% smaller is virtually identical to the 55% more nutrition–which means the nutrition per unit mass of an individual fruit is virtually identical but also means the nutrition per acre is at best identical, at worst is lower since the # of fruits is likely lower. But OTotherHand the nutrition is actually how much nutrition per SURFACE AREA. And the surface area is clearly lower for the smaller fruit, so the nutrition per area goes like r_0/r (or 1/r).

  • Mike Carney

    Maybe Jeffery Smiths studies should be looked at in SEEDS OF DECEPTION and his new book GENIC ROULET , The pitfalls in this new Pharming has already started to effect cattle, hogs and Us . What is disturbing Is the lack of response from the government and University’s . Well I guess it sounded good at the time. Were just starting to see its effect ,maybe Your editors are seeing GMOs with fresh eyes like other countries in the world.

  • Ummer Farooq

    You want smaller fruit? Go ask the farmer, he will tell you to add more clay into the soil, vermicasting mixture.

  • Kevin Bonham

    Was glad to see you express that caveat in the last paragraph, but your headline is incredibly misleading. The health benefits of nutritional antioxidants is murky to say the least, so saying that “organic is healthier” is a rather spurious conclusion.

    Also, Lauklejs’ makes a great point (re: nutrition is =, just not nutrition by mass)

  • ds800226

    Another important factor to consider is that antioxidants (even if they make it past the stomach) have not been shown to produce any actual health benefits. Same with vitamins; people that are well off enough to be in the position of choosing organic vs. not are virtually guaranteed to not be deficient in any vitamin and therefore would have no benefit at all to getting more.

  • DJ6ual

    The biggest problem is figuring out what IS and what IS NOT really organic anymore. Stores lie, companies lie, and even farmers lie just to make a profit in this economy. The only safe bet is to grow your own anymore and that isnt an option for everyone.


  • JonFrum

    What a terrible article. Organic crops get less nutrients? Try telling that to the organic-obsessives out there, who claim that organic crops get more, better nutrients. And organic tomatoes are tiny? The mind boggles. If a college freshman passed this in as an assignment, it would get a failing grade.


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