Can your saliva affect the way you shop?
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CES 2018: DNANudge app uses saliva to recommend what to eat

A UK start-up hopes to offer in-store DNA tests at top supermarkets, to help people eat more healthily.

The retailer Waitrose told the BBC it was "exploring" the idea, but geneticists question the thinking behind the proposal.

The tech will be one of many health-related innovations on show at the CES tech trade fair in Las Vegas next week.

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