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The Downside of Prewashed Greens

In All Health Watch, Diet and Nutrition, Featured Article

Prewashed, packaged greens have become wildly popular in recent years.

It’s so easy to pop open the bag and have greens ready to be tossed into a salad or stir fry.

No more washing.

No more drying with paper towels or salad spinners.

No more worrying that you haven’t gotten all the dirt off.

Prewashing has turned healthy food into fast food.

But it’s not all good news. All that convenience has a drawback.

Prewashed Greens Often Have Less Nutrition

 Studies have found that prewashing and chopping of commercially packaged greens accelerates nutrient loss. The vitamins that are stripped out the fastest are water-soluble ones. They include vitamins B and C, and carotenoids.[1]

The washing causes immediate vitamin C loss. The mechanical chopping of the leaves increases this loss.[2] [3]

Here’s how the nutrition loss shakes out:

Folate (vitamin B9): Ohio State researchers found that washed spinach retained only 53% of its folate (vitamin B9) after eight days.

A recent Norwegian study shows that chopped, washed lettuce loses up to 40% of its folate within just four hours.[4]

Vitamin C: Researchers at the University of Edinburgh revealed that by the time you eat prewashed lettuce, 59% of its vitamin C is lost.[5]

The same study, published in the journal Food Chemistry, found that mature spinach lost 80% of its vitamin C. Baby spinach lost up to 45%.

Carotenoids: The Ohio State study found that prewashed spinach retained only 54% of its carotenoids after eight days.

The University of Edinburgh study found that chopping greens also increased the content of an anti-nutrient called oxalate (oxalic acid). It binds to minerals in the gut and can stop the body from absorbing them. This makes greens less nutritious.[6]

How to Get the Most Nutrition from Your Greens

Prewashed greens are still super-healthy, even with the vitamin loss caused by washing and chopping.

But if you want maximum nutrition go for whole—not chopped—greens. And buy greens that are not prewashed.

If you don’t want to give up the convenience of prewashed, be sure to check the sell-by date on the bag. The fresher the better.

And whether you buy prewashed or not, go for organic greens. They are higher in nutrition than conventionally grown varieties. And more importantly, they contain no harmful pesticide residues
One more thing…

Farmers markets are just getting into full swing in many parts of the country. They are a great place to get fresh, organic greens. To maximize nutrition and flavor, eat them the same day you buy them.

Editor’s Note: Discover natural, non-drug methods to transform your health. Read our monthly journal, Independent Healing. It’s your best source for unbiased, evidence-based medical information. For more information, click HERE.

 

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References:

[1] https://www.nytimes.com/2017/11/03/well/eat/do-prepackaged-salad-greens-lose-their-nutrients.html?em_pos=small&emc=edit_hh_20171103&nl=well&nl_art=2&nlid=79817619&ref=headline&te=1

[2] http://www.sciencedirect.com/science/article/pii/S0308814617306556

[3] http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2621.2004.tb09919.x/full

[4] http://www.tandfonline.com/doi/full/10.1080/17482970701284510

[5] http://www.sciencedirect.com/science/article/pii/S0308814617306556

[6] https://www.healthline.com/nutrition/oxalate-good-or-bad#section3