Mars is to reduce the calories in its chocolate sold globally to 250 or less by the end of 2013.
Some of its chocolate bars already fall below the 250 benchmark. However, core brands such as the Mars bar, at 260 calories, and Snickers, at 296 calories, are above the threshold.
A Mars spokesperson said: “We believe that all of our products can be enjoyed as part of a healthy lifestyle and balanced diet - our commitment to making all our chocolate products no more than 250 calories per portion reflects this.
“These changes form part of our on-going efforts to encourage responsible consumption, and will come into effect globally by the end of next year.”