BMI has long been the method used to determine the health risks associated with individual’s weight. But it’s not without controversy and recently, providers have been urged to consider the wide range of factors that impact an individual’s weight, from gender, race/ethnic groups, age, and body composition. Using height and weight, BMI categorizes results into tiers ranging from “underweight” to “morbidly obese”. A new study sheds light on the impact of BMI on seniors’ longevity, specifically women.
54,437 women enrolled in the Women’s Health Initiative, a prospective study investigating causes of chronic diseases among postmenopausal women led by the University of California San Diego.
The results of the study were published in the Journal of Gerontology: Medical Sciences. The data revealed that maintaining stable weight after age 60 significantly boosts women’s odds of living past 90, known as exceptional longevity.
Several key takeaways from the study were:
- Older women who maintained stable weight were 1.2 to 2 times more likely to live past 90.
- Those who lost 5% or more weight were 51% less likely to achieve exceptional longevity.
- Gaining 5% or more weight, compared to stable weight, was not associated with exceptional longevity.
This latest study is the first of its kind to examine weight changes and the impact to longevity in older women specifically. The results contradict general recommendations that older people should lose weight to avoid health issues often linked to higher BMIs. Such concerns include cardiovascular disease, joint pain, diabetes, stroke, sleep apnea, and more.
Other studies have explored the relationship between BMI and the mortality rates of older people, with research showing that seniors who fall into the BMI range of 25-29.9 (overweight) have the lowest mortality rates. Other studies back up the data but have found the BMI that appears to promote longevity varies slightly- with the range sometimes widening to between 23-33 (between normal and obese).
Data also shows that a low BMI is unhealthy, especially for older adults. This information has led some, including the National Institutes of Health, to suggest that an ideal BMI for seniors is between 25 and 27 (overweight).
Yet another large study combined BMI data from 32 previous studies and was published in 2014 in American Journal of Clinical Nutrition. The researchers analyzed 197,940 adult participants (all older than age 65) who were followed for at least five years.
The researchers concluded that there was a higher risk of death when BMI was below 23 or above 33. Compared to a BMI of 23 to 23.9, the risk of mortality in older adults increased by:
- 12% for BMIs 21.0 to 21.9
- 19% for BMIs 20.0 to 20.9
- 8% for BMIs 33.0 to 33.9
It’s clear that the data from each study shifts the specific BMI recommendation for seniors. But what appears to be consistent from the variety of studies is that those that fall within the normal to the lower ranges of “obese” appear to have a lower mortality risk. The latest study which focused solely on senior women highlights a different facet to the topic, raising the question whether the benefit of maintaining a steady weight provides more benefit (i.e. longevity) at a more significant rate than decreasing the risk of health issues tied to higher BMIs.
-https://neurosciencenews.com/weight-stability-longevity-aging-23856/#:~:text=Key%20Facts%3A%201%20Older%20women%20who%20maintained%20stable,and%20its%20impact%20on%20exceptional%20longevity%20among%20women.
-https://academic.oup.com/biomedgerontology/advance-article/doi/10.1093/gerona/glad177/7246412
-https://jech.bmj.com/content/66/7/611
-https://linkinghub.elsevier.com/retrieve/pii/S0002916523050244
-https://medlineplus.gov/ency/article/007196.htm#
-https://www.verywellhealth.com/healthy-weight-and-bmi-range-for-older-adults-2223592
-https://www.ammfitness.co.uk/bmi-body-mass-calculator