Between losing some height and slowing metabolism, it can be easy for older people to gain weight.
https://duckduckgo.com/?q=body+mass+index+for+older+adults
However, evidence seems to be emerging that older people will live longer if they have more body fat than was previously thought best. The body mass index is often calculated from a person's height and weight. The person's age and sex is often ignored.
BMI in Adults vs. BMI in Older Adults
May 21, 2020
BMI in the Elderly: What You Need to Know - The Geriatric ...
You can see that younger adults can be considered overweight with a Body Mass Index of 25 while an older adult with a body mass index of 30 is "Normal".
