SCHAUMBURG, Ill. — Store brands comprise almost 40% of items making health and wellness claims related to preservative; one in four organic product sales; and nearly one in five items making natural and fat claims in food, drug and mass channels, according to the Nielsen Co.

It found that GMO-free claims are the fastest growing among store brands. Sales of these items increased 67% in 2009 to $60.2 million, followed in popularity by gluten free (62%), absence of specific fat (53%) and lowers cholesterol (45%) store brands.

Private-label marketers are steering clear of other health and wellness claims for the time being, according to Tom Pirovano, director of industry insights at Nielsen.

“Store-brand development lags with respect to the products with newer claims such as high fructose corn syrup free, with many retailers adopting a wait-and-see attitude to determine if a claim has ‘legs’ or is merely the latest blip on the consumer trend screen,” he said in a blog post.

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