Obesity kills but is losing weight in old age also risky ?

Losing weight is a New year resolution for many people. There is no doubt that having a normal weight is healthy overall.

But there is always some degree of uncertainty with any health advice and this BMJ paper certainly gives “food for thought”.

Before you read further , you have understand that there are varying degrees of being overweight. BMI ( Body mass index) is the scientific way of looking at body weight issues and it is calculated using height and weight.

Based on BMI, people are usually classified into three groups:

(a) underweight and normal weight (BMI<25)

b) overweight (BMI 25.0-29.9)

(c) obese (BMI ≥30.0)

There is no doubt that obesity is bad for health. The BMJ paper not supringly found obesity in adulthood increased the risk death.

But, intriguingly, just being overweight only without being obese does NOT seem to have MAJOR impact on risk of death in adults.

Paradoxically, the study found that “weight loss from middle to late adulthood was associated with increased risk of death”

It is large well designed study but nevertheless results of observational studies need to be interpreted with caution.

The message from this study is “do not gain excessive weight during early adulthood“. Losing the excessive weight later on might not undo the damage already done to the body.


(1) Weight change across adulthood in relation to all cause and cause specific mortality: prospective cohort study.

BMJ 2019; 367 doi: https://doi.org/10.1136/bmj.l5584 (Published 16 October 2019) Cite this as: BMJ 2019;367:l5584

(2) Free NHS calculator for BMI ( Body mass index calculation) and advice regarding Body mass index.

Disclaimer: Please note- This blog is NOT medical advice. This blog is purely for information only and do check the the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you.

The views expressed in this blog represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not necessarily endorsed by any organisation the author is associated with and views are not substitute for professional advice.