Scientists in the United States have discovered three things which help predict how long someone is going to live.

In a study published in the journal Science, they report that the length of a person’s life is related to their body temperature, and to levels of two chemicals, insulin and DHEAS, circulating in the blood.

On average, people who have a lower body temperature live longer, as do those with lower levels of insulin, and those with higher levels of DHEAS.

The researchers are not entirely sure of the reasons behind this finding but experiments with animals suggest it may be to do with a lower metabolic rate.