People over 80 with ‘overweight’ BMI may have lower mortality rates

Murugesu was written by Jason Arunn.

A large-scale analysis in China has found that people over the age of 80 have a lower mortality rate if their body mass index is higher than currently recommended. Weight guidelines should be changed for this age group according to the findings.

A person's body mass index scores are used to determine if they have a healthy weight. It is based on a person's height and weight, and most guidelines suggest that someone with a score above 25 is overweight, while those with scores above 30 are considered obese.

The Chinese Center for Disease Control and Prevention in Beijing says the guidelines are mostly based on younger age groups. He says that it is important to make sure that the recommendations make sense for older age groups.

Shi and his colleagues studied mortality risk in more than 27,000 people over the course of a decade. The participants in the study were followed up until their deaths or at least until they were 93 years old.

This is the first study to look at this question with such a large sample size, and it has found a link between higher BMI scores in older age groups and a lower mortality rate.

The optimal body mass index for the over-80s was 29 according to the analysis. Cancer or respiratory disease are causes that have a lower risk of death. The group had a lower risk of death from cardiovascular diseases.

The mortality rate for people with a body mass index between 30 and 35 was lower than the mortality rate for people in the 20 to 25 range.

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Socioeconomic status, education background, and whether a person smoked were some of the factors accounted for by the team.

Shi theorizes that people with a better diet may be linked with a lower mortality rate. The population's body mass index scores were lower than those found in the West. He says that the findings may not be applicable to other age groups and ethnic groups.

Louise Baur says that the study shows the importance of taking age into account when looking at the relation between body mass index and mortality or other health risks. She agrees that it may be due to better nutrition that being overweight is linked to better health outcomes.

Nicholas Fuller is a researcher at the University of Sydney and he says that a single measure of health shouldn't be relied on. It is more important to focus on measures that tell us more about fat in the body and where it is distributed, such as waist circumference, to get a better understanding of health and risk.

Nature Aging is a journal.

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