Change in Percentages of Adults With Overweight or Obesity Trying to Lose Weight, 1988-2014

Socially acceptable body weight is increasing.¹ If more individuals who are overweight or obese are satisfied with their weight, fewer might be motivated to lose unhealthy weight. This study assessed the trend in the percentage of adults who were overweight or obese and trying to lose weight during 3 periods from 1988 through 2014.

We used data from the National Health and Nutrition Examination Survey (NHANES), an ongoing, stratified, multistage probability sample of the US noninstitutionalized population designed to represent the health and nutritional status of the general population. A strength of NHANES is that the sampling approaches, interviews, and physical examination methods are standardized across surveys and have been published extensively elsewhere.² NHANES protocol was approved by the National Center for Health Statistics institutional review board, and written informed consent was obtained.² The current analysis was categorized as exempt by the Georgia Southern University institutional review board.

Periods examined in the current report were 1988-1994, 1999-2004, and 2009-2014. Response rates were approximately 80% with consistent nonresponse patterns across the 3 periods.³ Participants aged 20 to 59 years who were overweight (a body mass index [BMI; calculated as weight in kilograms divided by height in meters squared] of ≥25-<30) or obese (BMI ≥30) were included. Because overweight and obesity vary by race/ethnicity,⁴ results are presented by race/ethnicity. The question of interest was “During the past 12 months, have you tried to lose weight?” and asked directly during the 1988-1994 survey period. However, a skip pattern was integrated with this question for the 1999-2004 and 2009-2014 surveys. Adults who reported that their body weight in the previous year was 10 pounds more than their current weight and that this change was intentional were presumed to “have tried to lose weight in the past 12 months” and the question about having tried to lose weight was skipped. The question of interest was asked of all other participants, including those with an unintentional weight loss of 10 pounds or more. Because the percentage of adults who reported trying to lose weight was substantially higher than 10%, modified Poisson regression⁵ was used to estimate percentage ratios and compare the percentage of adults who reported trying to lose weight among those who were overweight or obese over the 3 periods. With family income, age, and body weight as covariates, regressions were run for each sex and race/ethnicity group. Participants with missing information on family income were excluded.

With appropriate weighting and nesting variables, analyses were conducted using SAS (SAS Institute), version 9.4. Two-sided P values <.05 were considered significant. No adjustment for multiple testing was performed.

Of 29 088 participants analyzed, most were white (75% in 1988-1994, 69% in 1999-2004, and 64% in 2009-2014). Overweight and obesity prevalence increased throughout the study period, from 52.72% (95% CI, 50.76%-54.68%) in 1988-1994 to 68.20% (95% CI, 66.26%-70.15%) in 2009-2014 (Table).

The percentages of adults who were overweight or obese and reported trying to lose weight declined from 55.65% (95% CI, 53.61%-57.69%) in 1988-1994 to 54.71% (95% CI, 52.67%-56.75%) in 1999-2004, then increased to 57.85% (95% CI, 56.51%-59.19%) in 2009-2014. However, after adjustment, percentage ratios, compared with 1988-1994, were 0.94 (95% CI, 0.89-1.00) in 1999-2004 and 0.91 (95% CI, 0.84-1.00) in 2009-2014 (P for trend = .046).

Declines occurred among white women (from 72.86% [95% CI, 69.26%-76.45%] in 1988-1994 to 69.20% [95% CI, 66.18%-72.23%] in 2009-2014) and black women (from 65.50% [95% CI, 62.73%-68.26%] in 1988-1994 to 62.29% [95% CI, 60.16%-64.41%] in 2009-2014). Adjusted percentage ratios among white women, compared with 1988-1994, were 0.87 (95% CI, 0.76-1.00) in 1999-2004 and 0.81 (95% CI, 0.67-0.99) in 2009-2014 (P for trend = .04). Among black women, the adjusted percentage ratios, compared with 1988-1994, were 0.86 (95% CI, 0.74-0.99) in 1999-2004 and 0.79 (95% CI, 0.64-0.99) in 2009-2014 (P for trend = .04).

This study found inconclusive results for trends in the percentage of overweight or obese adults who reported trying to lose weight between 1988 and 2014, although the trends were statistically significant for white and black women. The results in women may be due to body weight misperception reducing motivation to engage in weight loss efforts or primary care clinicians not discussing weight issues with patients.⁶ The chronicity of obesity may also contribute. The longer adults live with obesity, the less they may be willing to attempt weight loss, in particular if they had attempted weight loss multiple times without success.

Black women have a disproportionate burden of excess body weight and associated morbidity. They had the highest prevalence of obesity in the current study, making the decline in reports of trying to lose weight among black women especially concerning. Limitations of the study include use of self-reported data with the potential for social desirability bias, the restriction to nonelderly adults, and the change in how intentional weight loss was asked after the first survey.

Corresponding Author: Jian Zhang, MD, DrPH, Jiann-Ping Hsu College of Public Health, Georgia Southern University, PO Box 8015, Statesboro, GA 30460 (jianzhang@georgiasouthern.edu).

Retraction and Replacement: This article was retracted and replaced on December 18, 2018, to fix wording and data errors in the Methods, Results, and Discussion sections of the text and in the Table (see Supplement 1 for the retracted article with errors highlighted and Supplement 2 for the replacement article with corrections highlighted).

Author Contributions: Dr Zhang had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Snook, Hansen, Hackney, Zhang.

Acquisition, analysis, or interpretation of data: Snook, Hansen, Duke, Finch, Zhang.

Drafting of the manuscript: Snook, Hansen, Duke, Finch.

Critical revision of the manuscript for important intellectual content: Snook, Hansen, Duke, Hackney, Zhang.

Statistical analysis: Snook, Finch, Zhang.

Administrative, technical, or material support: Hansen, Duke, Zhang.

Supervision: Hansen, Hackney, Zhang.

Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.

Additional Contributions: We thank Yanfeng Li, MD, MPH (US Centers for Disease Control and Prevention), for assistance with statistical analyses. No compensation was provided for the consulting service. This article was initially prepared as a group project for graduate students enrolled in a seminar on public health surveillance led by Dr Zhang at Jiann-Ping Hsu College of Public Health at Georgia Southern University.