Self-reported BMI bias estimates increasing due to weight bias, not weight loss

The gap between obesity levels measured by self-reported height and weight and obesity recorded by measured height and weight is increasing. This is due to an increasing bias in self-reported weight, according to research published January 23 in the open access journal PLOS ONE by Frances Shiely and colleagues from University College of Cork, Ireland.

BMI is a ratio of height and used clinically to assess whether an individual's weight is in a healthy range. Previous studies have shown that people tend to over-estimate their own height and under-estimate their weight and it is generally assumed that both are responsible for under-estimation of self-reported BMI. The authors of this study have shown in previous work that under-estimation of BMI is increasing over time. Here, they assess whether this increasing inaccuracy is due to changing biases in self-reported height, weight, or both, using data from a representative sample of Irish adults.

The researchers found that the in self-reported height has remained stable over the last ten years regardless of gender, age or clinical BMI category. However, biases in self-reported weight have increased over time for both genders and in all age groups. The bias towards reporting a lower weight is most notable in those who are obese.

The authors state that knowing why self-reported scores are decreasing while clinically measured BMIs are not "brings us one step closer to accurately estimating true obesity levels in the population."

More information: Shiely F, Hayes K, Perry IJ, Kelleher CC (2013) Height and Weight Bias: The Influence of Time. PLoS ONE 8(1): e54386. doi:10.1371/journal.pone.0054386

add to favorites email to friend print save as pdf

Related Stories

Most people fudge numbers on weight and height surveys

Jan 27, 2012

When people in the U.S. are asked to provide their weight for research surveys, they underestimate their weight and overestimate their height, despite numerous public reports about increasing rates of obesity. ...

Rethinking body mass index for assessing cancer risk

Nov 08, 2012

A study by researchers at Albert Einstein College of Medicine of Yeshiva University suggests that body mass index (BMI)—the most commonly used weight-for-height formula for estimating fatness—may not be the best measure ...

Recommended for you

Divorce fuels sugary beverage consumption, study finds

7 hours ago

Children of recently separated or divorced families are likelier to drink sugar-sweetened beverages than children in families where the parents are married, putting them at higher risk for obesity later in life, according ...

People watching tearjerkers eat 28-55% more

Mar 02, 2015

Sad movies are bad news for diets. A newly reported study from the Cornell Food and Brand Lab showed movie-goers watching tearjerkers ate between 28% and 55% more popcorn both in the lab and in a mall theater ...

Abdominal obesity ups risk of hip fracture

Feb 27, 2015

(HealthDay)—Abdominal obesity is associated with increased risk of hip fracture, according to a study published in the March issue of the Journal of Internal Medicine.

Does traffic noise increase the risk of obesity?

Feb 27, 2015

There is an association between road traffic noise and the risk of obesity among people who are particularly sensitive to noise, according to a study from the Norwegian Institute of Public Health.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.