"Lifestyle factors could have a bearing on the premium that you pay - and it's likely that different insurers will use different measures to determine lifestyle factors. Obesity is going to be one such factor - some [insurers] will use body mass index ratings, others will use other measures," Jonathan French, press officer for the ABI, said.
"If you are obese there is a higher risk of other health problems resulting from that, and therefore the risk of a claim is going to be higher and insurers will price their policy accordingly."
Payouts will not be lowered as a result of obesity however, according to the expert.
"The sum assured is not affected in any way by the reasons for claims - they're a constant which is set at the beginning of the policy," he said.
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