The Influence of Weight Status Duration on Weight Perception Accuracy

Abstract

Purpose:

To examine the association between weight status duration and weight perception accuracy.

Design:

Retrospective study.

Setting:

National Health and Nutrition Examination Survey 2003 to 2006.

Sample:

A total of 4029 adults aged 20 years or older.

Measures:

To assess weight status duration, participants’ past (10 years ago) and present body mass indexes were used to create 4 groups: normal weight in the past and present (group 1), normal weight in the past but overweight/obese in the present (group 2), overweight/obese in the present but not in the past (group 3), and overweight/obese in the past and present (group 4). We classified individuals as having an accurate/inaccurate weight perception based on present body mass index and whether they considered themselves as overweight, underweight, or about the right weight.

Analysis:

Logistic regression.

Results:

Our findings suggest that participants who were overweight/obese in the past, present, or during both time periods had increased odds of possessing an inaccurate weight perception. Furthermore, being normal weight in the past but obese in the present increased the odds of having an inaccurate weight perception nearly 10-fold and almost 5-fold for those obese in both the past and present.

Conclusion:

Studies such as this can aid clinicians in identifying individuals who may have increased odds of inaccurately identifying their weight status, thereby providing additional opportunities to facilitate weight loss.

Keywords

weight history perceived weight body mass index weight management

Purpose

Over the past few decades, prevalence rates of overweight/obesity in the United States have continually risen. Research suggests that approximately 69% of the adult population is classified as overweight/obese.¹ Moreover, it has been estimated that 77% of males and 71% of females are expected to be overweight, and 40% of males and 43% of females are expected to be obese by the year 2020.² Among the primary reasons, excess weight is considered problematic for the resulting negative health outcomes. Overweight/obesity is an established risk factor for several of the leading causes of death, as well as development of hypertension, type 2 diabetes, coronary heart disease, stroke, and some cancers.³ Due to the aforementioned health implications and sizable number of adults exceeding weight recommendations, increasing the proportion of adults who are in the healthy weight group was identified as a national objective of Healthy People 2020.⁴ Consequently, there is a need for effective obesity prevention and treatment protocol.

Although obesity reduction discourse has most commonly emphasized behavior modification, diet, and physical activity,⁵ another factor worth considering is the weight perception. Weight perception has been defined as how an individual perceives his or her body weight and is affected by “ideal” and “normative” body images.⁶ Some individuals perceive themselves as being normal weight, despite having an excess body fat percentage (eg, underestimate weight). Conversely, other individuals perceive themselves as being overweight, despite having a normal body fat percentage (eg, overestimate weight).⁷ When perceived and actual weight statuses are incongruent, individuals are said to possess an inaccurate weight perception. This phenomenon is notable partly because inaccurate weight perceptions, particularly underestimating weight, can impede recognition of susceptibility to weight-related health risks and decrease the likelihood of individuals following physical activity and nutrition guidelines.^8

-11

Despite the role inaccurate weight perception may have in precluding national obesity reduction efforts, few quantitative studies have examined factors contributing to its incidence, such as weight history. For instance, as obesity rates have increased, the proportion of individuals who accurately identify themselves as such has decreased.¹² This indicates many are failing to recognize vicissitudes in body size, perhaps due to obesity becoming more commonplace within peer groups and society as a whole.¹³ Hence, individuals are possibly becoming desensitized to changes in personal weight status and experiencing a diminished ability to adjust weight perceptions to align with clinically identifiable shifts in weight over time.¹⁴

While a seemingly plausible factor, little is known about the influence of weight status duration (WSD) on perceptions of present day weight. Therefore, the primary purpose of this retrospective study was to examine whether WSD (ie, being overweight for long or short periods of time) is associated with perception of present day weight (ie, accurate/inaccurate perception). We hypothesized those who were overweight/obese in the past and in the present, as well as those who were overweight/obese in the present, but not in the past, would be more likely to possess an inaccurate weight perception.

Methods

Design

Data for this study were from the 2003 to 2006 National Health and Nutrition Examination Survey (NHANES), which were the only cycles that included accelerometer-assessed physical activity, an important covariate to consider in this study.¹⁵ The NHANES is a cross-sectional survey conducted by the National Center for Health Statistics (NCHS) to evaluate the health status of noninstitutionalized US citizens through a complex, multistage, probability design.

Sample

The present study included 4029 adults aged 20 years or older. Participants provided written informed consent before data collection, and the NCHS ethics committee approved the study.

Measures

Weight status duration

Current height and weight were objectively measured and used to calculate participants’ “present” body mass index (BMI). Self-reported weight from 10 years prior and present height were used to calculate “past” BMI. Notably, previous work demonstrates evidence of convergent validity for past recall of weight.¹⁶ Overweight/obese was defined as having a BMI ≥ 25, and obese was defined as having a BMI ≥ 30. From this, we created WSD variables by categorizing participants into the following 4 groups:

Group 1: normal weight (BMI: 18.5-24.9 kg/m²) in the past and present

Group 2: normal weight in the past but overweight/obese (BMI: 25+ kg/m²) in the present

Group 3: overweight/obese (or obese) in the past but normal weight in the present

Group 4: overweight/obese (or obese) in the past and present

Weight perception

To assess weight perception, height and weight were objectively measured and used to calculate participants’ BMI. Participants were also asked, “Do you consider yourself now to be overweight, underweight, or about the right weight.” We created weight perception variables by placing participants into 1 of the following 2 categories:

Participants who were a normal weight (ie, present day BMI between 18.5 and 24.9) and self-reported being “about the right weight,” were labeled as “accurate perception.”

Participants who reported being “about the right weight” but were overweight (ie, BMI was ≥25) and those who reported being “overweight” but were normal weight (BMI between 18.5 and 24.9) were labeled as “inaccurate perception.” The few participants with a BMI <18.5 were excluded from the analyses.

Covariates

Based on prior studies on this topic, the following covariates were included in the model: age, gender, race–ethnicity, socioeconomic status, and moderate to vigorous physical activity (MVPA).^15,17 Age, gender, and race–ethnicity were self-reported. The MVPA was objectively measured using ActiGraph 7164 (Pensacola, FL) accelerometers, which were worn by participants on their right hip for 7 days; estimates for MVPA were summarized in 1-minute epochs. Activity counts >2020 per minute were classified as MVPA.¹⁸ Socioeconomic status was assessed using the poverty income ratio (PIR). Ranging from 0 to 5, PIR was defined as the ratio of the family income to the federal poverty threshold. For example, a PIR of 0.5 suggests that the family income is 50% below the poverty threshold.

Analysis

A multivariate logistic regression was computed, using Stata (Versoin 12), to assess the influence of WSD (independent variable) on weight perception (dependent variable). For the WSD variable, group 1 served as the referent group. Analyses were computed separately for those who were overweight/obese or just obese during present day.

Results

Overweight/Obese

Table 1 displays the weighted sample characteristics, and Figure 1 displays the regression associations between WSD and weight perception. In the initial analysis of overweight/obese duration, those who were normal weight in the past but overweight/obese in the present (group 2), overweight/obese in the past but not in the present (group 3), and overweight/obese in the past and present (group 4) had an increased odds of possessing an inaccurate weight perception in comparison to those who were normal weight in the past and present (group 1): group 2 versus group 1 (odds ratio [OR] = 1.32, 95% confidence interval [CI]: 0.98-1.79, P = .05), group 3 versus group 1 (OR = 2.86, 95% CI: 1.65-4.97, P < .001), and group 4 versus group 1 (OR = 2.06, 95% CI: 1.66-2.57, P < .001). With regard to the covariates, females (vs males) had a 73% increased odds of possessing an inaccurate weight perception (OR = 1.73, 95% CI: 1.50-1.99, P < .001), and for 1-year increase in age, participants had a 2% reduced odds of having a discrepant weight perception (OR = 0.98, 95% CI: 0.97-0.99, P = .009). Non-Hispanic whites (OR = 1.49, 95% CI: 1.12-1.98, P = .01) and those of other/multiraces (OR = 1.79, 95% CI: 1.04-3.07, P = .04) also had increased odds of possessing a discrepant weight perception when compared to Mexican Americans.

Table 1.

Weighted Sample Characteristics, NHANES 2003 to 2006 (N = 4029).

	Sample Size	Mean/Proportion	95% Confidence Intervals
Demographics
Age, years	4029	54.5	53.6-55.4
Gender, female	1934	48%
Race/ethnicity
Mexican American	226	5.60%
Other Hispanic	117	2.90%
Non-Hispanic white	3082	76.50%
Non-Hispanic black	419	10.40%
Other/Multi	185	4.60%
Poverty-to-income ratio	4029	3.13	3.0-3.4
Physical activity, min/day of MVPA	4029	21.09	19.84-22.34
Weight perception
Accurate	1019	22.60%
Inaccurate	3010	77.40%
Weight duration
Group 1^a	898	22.28%
Group 2^b	743	18.43%
Group 3^c	147	3.67%
Group 4^d	2241	55.62%

Abbreviations: NHANES, National Health and Nutrition Examination Survey; MVPA, Moderate-to-vigorous physical activity.

^aNormal weight in the past and present.

^bNormal weight in the past but overweight/obese in the present.

^cOverweight/obese in the past but normal weight in the present.

^dOverweight/obese in the past and present.

Figure 1.

Odds of having an inaccurate weight perception. Group 1 = normal weight in the past and present. Group 2 = normal weight in the past but overweight/obese in the present. Group 3 = overweight/obese in the past but normal weight in the present. Group 4 = overweight/obese in the past and present.

Obese

After recomputing the model to include duration of obesity only, there were some notable differences. Those who were normal weight in the past but obese in the present (group 2), as well as those obese in the past and present (group 4), had an increased odds of possessing an inaccurate weight perception compared to those who were normal weight in the past and present (group 1): group 2 versus group 1 (OR = 10.65, 95% CI: 7.24-15.66, P < .001) and group 4 versus group 1 (OR = 5.83, 95% CI: 3.86-8.82, P < .001). Notably, group 3 versus group 1 was not significant (OR = 0.79, 95% CI: 0.51-1.22, P = .28). Similar to the previous model, females (vs males) were 58% more likely to possess an inaccurate weight perception (OR = 1.58, 95% CI: 1.37-1.82, P ≤ .001). Likewise, Non-Hispanic whites (OR = 1.49, 95% CI: 1.10-2.01, P = .01) and those of other/multiraces (OR = 1.87, 95% CI: 1.08-3.23, P = .03) had increased odds of possessing an inaccurate weight perception.

Discussion

Summary

The purpose of this study was to examine the association between WSD and weight perception accuracy. Our findings suggest that participants who were normal weight in the past but overweight/obese in the present and those who were overweight/obese during both time periods had increased odds of possessing an inaccurate weight perception. Furthermore, being normal weight in the past but obese in the present increased the odds of having an inaccurate weight perception nearly 10-fold and almost 5-fold for those obese in both the past and present. Research suggests that ideals regarding personal body size are malleable and influenced by societal norms.¹⁹ Therefore, a likely explanation for the present findings is that larger body sizes are becoming increasingly acceptable within our society, and the prevalence of excess weight has an obesogenic effect on the population. As the average BMI of Americans increases, the ability to accurately assess personal weight may decrease.

Limitations

Strengths of this study include the use of a large nationally representative sample and objectively measured weight and height to establish participants’ present BMI. However, there are limitations that must be acknowledged. First, inferences based on these results are limited to associations due to the retrospective nature of the study. Well-designed prospective studies are required to determine whether WSD is causally related to weight perception. Also, given that past-BMI was calculated based on participant recall of weight 10 years prior, assessment of weight duration could be imprecise. However, there is evidence of construct validity for past recall of weight.¹⁶

Significance

Prior studies have established the prevalence of inaccurate weight perceptions, but to our knowledge, no studies have specifically examined the influence of weight history on weight perception. Our findings extend upon current literature suggesting females are more likely to have an inaccurate weight perception.^20,21 Due to the paucity of research in this area, attention should be given to the role weight history has in the development of inaccurate weight perceptions. This is particularly true for females, non-Hispanic whites, and multiracial individuals. Gaining a better understanding of weight perception inaccuracies among these populations could improve their body size awareness and likelihood of adherence to weight reduction recommendations.

Importantly, our definition of inaccurate weight perception included those who overestimated their weight (ie, reported being overweight but were normal weight). This would be of particular concern when communicating risks associated with overweight/obesity to normal or underweight patients, since prior research suggests those who overestimate weight are at an increased risk of engaging in unhealthy weight control practices.²² Therefore, clinicians should provide patient-specific weight management counseling. A potential barrier clinicians may face during this process is the discordance between medical definitions of overweight/obesity and patient’s perceived weight status.

If patients are unaware of the fact that their weight status is problematic or if they are content with their current weight status, simply providing educational information as a method of weight management counseling may be less likely to yield sustained behavior changes. Accurately perceiving oneself as overweight/obese is positively associated with weight loss attempts.²³ Therefore, a critical component in any weight reduction intervention should include ensuring patients are aware of their objectively measured body size and fully comprehend the associated risks. It is also important for clinicians to take into consideration the individuals’ readiness to change. The transtheoretical model (TTM) of behavior change can be a useful tool during this process. Many individuals who possess inaccurate weight perceptions will likely be in the precontemplation stage of the TTM; it is during this initial stage that patients are not considering behavior change during the following 6 months or are unaware of their need for weight reduction. Clinicians can assist patients in evaluating current health behaviors (ie, diet and physical activity level) in relation to their weight status and use that information to develop a patient-specific action plan for weight reduction. Self-monitoring should be included in this process and the action plan reexamined and revised, as necessary, during the patient’s transition through each stage of the TTM.

In conclusion, for weight reduction efforts to be successful, attention must be given to the relevance of weight perception. Studies such as this can aid clinicians in identifying individuals who may have increased odds of inaccurately identifying their weight status. Clinicians can then facilitate weight reduction among those populations by attempting to converge actual and perceived weight statuses. This may be the first step in reducing the prevalence of obesity in the United States.

So What?

What is already known on this topic?

Overweight and obesity rates are high in the United States. Inaccurate weight perceptions can influence the adoption of health behaviors.

What does this article add?

Our findings demonstrate that weight status duration may play an important role in shaping weight status perceptions.

What are the implications for health promotion practice or research?

While further studies are needed, the present findings provide useful insight for health-care professionals since overweight/obesity is commonly encountered in clinical practice, yet less commonly diagnosed.²⁴ This is concerning given that prior research suggests as BMI increases, so does the likelihood of morbidity and mortality from chronic diseases.²⁵ However, if overweight/obese individuals lost even 5% to 10% of their body weight, they could delay or prevent many of the associated negative health outcomes.²⁶ Consequently, it is becoming increasingly important for clinicians to document diagnoses of overweight/obese individuals and prescribe weight reduction plans.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

References

Ogden

Carroll

Kit

Flegal

. Prevalence of childhood and adult obesity in the United States, 2011–2012. Surv Anesth. 2014;58(4):206.

Ruhm

. Current and future prevalence of obesity and severe obesity in the United States. Forum Health Econ Policy. 2007;10(2):1–26.

Centers for Disease Control and Prevention. Surveillance for certain health behaviors among states and selected local areas—United States, 2010. MMWR Morb Mortal Wkly Rep. 2013; 62(ss01):1–247.

Nutrition and Weight Status. Office of Disease Prevention and Health Promotion Web site. https://www.healthypeople.gov/2020/topics-objectives/topic/nutrition-and-weight-status/objectives. Published 2015. Updated March 23, 2016. Accessed March 23, 2016.

Thompson

Cook

Clark

Bardia

Levine

. Treatment of obesity. Mayo Clin Proc. 2007;82(1):93–102.

Park

. Overestimation and underestimation: adolescents’ weight perception in comparison to BMI-based weight status and how it varies across socio-demographic factors. J Sch Health. 2011;81(2):57–64.

Duncan

Wolin

Scharoun-Lee

Ding

Warner

Bennett

. Does perception equal reality? Weight misperception in relation to weight-related attitudes and behaviors among overweight and obese US adults. Int J Behav Nutr Phys Act. 2011;8(1):20.

Gregory

Blanck

Gillespie

Maynard

Serdula

. Perceived health risk of excess body weight among overweight and obese men and women: differences by sex. Prev Med. 2008;47(1):46–52.

Loprinzi

. Factors influencing the disconnect between self-perceived health status and actual health profile: implications for improving self-awareness of health status. Prev Med. 2015;73:37–39.

10.

Kuk

Ardern

Church

Hebert

Sui

Blair

. Ideal weight and weight satisfaction: association with health practices. Am J Epidemiol. 2009;170(4):456–463.

11.

Powell

. Body size misperception: a novel determinant in the obesity epidemic. Arch Intern Med. 2010;170(18):1695–1697.

12.

Kuchler

Variyam

. Mistakes were made: misperception as a barrier to reducing overweight. Int J Obes Relat Metab Disord. 2003;27(7):856–861.

13.

Christakis

Fowler

. The spread of obesity in a large social network over 32 years. N Engl J Med. 2007;357(4):370–379.

14.

Bagrowicz

Watanabe

Umezaki

. Is obesity contagious by way of body image? A study on Japanese female students in the United States. J Community Health. 2013;38(5):834–837.

15.

Coleman

Loprinzi

. The association between discrepant weight perceptions and objectively measured physical activity. Prev Med. 2016;87:47–50.

16.

Troy

Hunter

Manson

Colditz

Stampfer

Willett

. The validity of recalled weight among younger women. Int J Obes Relat Metab Disord. 1995;19(8):570–572.

17.

Chang

Christakis

. Self-perception of weight appropriateness in the United States. Am J Prev Med. 2003;24(4):332–339.

18.

Torino

Berrigan

Dodd

Masse

Tilert

McDowell

. Physical activity in the United States measured by accelerometer. Med Sci Sport Exer. 2008;40(1):181–188.

19.

Bair

Steele

Mills

. Do these norms make me look fat? The effect of exposure to others’ body preferences on personal body ideals. Body Image. 2014;11(3):275–281.

20.

Gunnare

Silliman

Morris

. Accuracy of self-reported weight and role of gender, body mass index, weight satisfaction, weighing behavior, and physical activity among rural college students. Body Image. 2013;10(3):406–410.

21.

Wen

Kowaleski-Jones

. Sex and ethnic differences in validity of self-reported adult height, weight and body mass index. Ethn Dis. 2012;22(1):72–78.

22.

Ibrahim

El-Kamary

Bailey

George

DMS

. Inaccurate weight perception is associated with extreme weight-management practices in US high school students. J Pediatr Gastroent Nutr. 2014;58(3):368–375.

23.

Bardia

Holtan

Slezak

Thompson

. Diagnosis of obesity by primary care physicians and impact on obesity management. Mayo Clin Proc. 2007;82(8):927–932.

24.

Lemon

Rosal

Zapka

Borg

Andersen

. Contributions of weight perceptions to weight loss attempts: difference by body mass index and gender. Body Image. 2008;6(2009):90–96.

25.

Flegal

Graubard

. Estimates of excess deaths associated with body mass index and other anthropometric variables. Am J Clin Nutr. 2009;89(4):1213–1219.

26.

Obesity. US National Library of Medicine Web site. https://www.nlm.nih.gov/medlineplus/obesity.html#cat79. Published 2015. Updated March 17, 2016. Accessed March 23, 2016.