“The people in the trials we analyzed only reduced their salt intake by a moderate amount, so the effect on blood pressure and heart disease was not large,” he said.

For this review, Taylor’s team found seven studies that together included 6,489 participants. This gave the researchers enough data to be able to start drawing conclusions, they said. But even so, the scientists think they would need to have data from at least 18,000 people before they could expect to identify any clear health benefits.

Elaine Rush, a professor of nutrition at Auckland University of Technology in Australia, said that putting a spotlight on single trials and generalizing dietary advice for a single nutrient such as salt was “not helpful.”

“What is helpful is for the food industry to reformulate products to reduce sodium and increase the nutrient quality of foods by using real ingredients,” she said in an emailed comment.

###
By Kate Kelland
LONDON