Countdown will stop selling energy drinks to people under the age of 16 from September 2.
The supermarket confirmed the plans on Saturday after media reports and rumours it was planning on bringing in age restrictions surfaced on Friday.
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All 180 stores across the country will implement the age restrictions on the 74 different energy products Countdown currently sells.
University of Auckland public health academic Simon Thornley praised the plan, in a statement provided alongside the Countdown announcement.
"The sugar and caffeine in these drinks leads to children getting hooked on them, with rotten teeth and poor engagement in the classroom as predictable consequences. An age restriction makes sense."
But Countdown's main competitor Foodstuffs, which owns New World and Pak'nSave, won't be following suit.
"Research shows people under the ages of 16 are not high consumers of these types of products, however it is important to us that we provide customers with the information they need to make informed decisions," a spokesperson said.
"Foodstuffs' focus is on educating children and their parents on how to make better choices in general."