Ideal body weight: A commentary

Abstract

Background & aims: The Ideal Body Weight (IBW) model has provided dietitians and researchers with a quick method of risk assessment but is known to be imperfect. IBW formulas were developed from anthropometric measurements of life-insurance policy holders obtained between 1885 and 1908, providing statistics of mortality, organized by sex and age. Actuaries of the U.S. life insurance companies published data on the impact of overweight/obese status and mortality risk. Research of the same era repeatedly revealed either no significance or an inverse relationship. The intent of this text is to draw attention to the complexity and overall discussion of utility of the IBW method.

Methods: Reviewed relevant literature from the development of IBW through the recent findings in 2014.

Results: Height, weight, and frame fail to consider comorbidities and genetics. IBW formulas assume that weight increases as a linear function of height. Weight has been shown to increase not just as a function of height, but also of volume: body width, trunk length, and musculature. Depending on standards of practice, several equations may be used.

Conclusions: The IBW model is utilized but not limited to creating enteral and parenteral feeding plans, avoiding malnutrition, aiding weight management, identifying transplant eligibility, and determining inclusion or exclusion from research studies. Socially, the significance around "ideal" can impact a weight-centric mentality and negatively affect a large portion of the population. Every individual has a distinct "ideal" body weight based on genetics, environment and lifestyle, which could be represented and assessed effectively with new tools.

Keywords: BMI; Ideal body weight; Met life tables; Nutrition assessment; Predictive formulas.

Figure 1:

Timeline of the development of the IBW model

1. Dark blue box represents the title of the publication (book, article, table)

2. Blue outlined white box represents the year of publication, attribution and brief summary of publication results

3. Top row, read from left to right, light blue arrows pointing in the direction of the progression. Bottom row, read from left to right, light blue arrows pointing in the direction of the progression.

4. Each publication in the timeline a catalyst for the next project/development in the ideal body weight timeline

References: Medico-Actuarial Mortality Investigation. Vol. 1. New York, NY, USA: Association of Life Insurance Medical Directors; The Actuarial Society of America; 1912. Dublin L. I, Lotha A. J. Twenty-Five Years of Health Progress: A Study of the Mortality Experience among the Industrial Policyholders of the Metropolitan Life Insurance Company, 1911 to 1935. New York, NY, USA: Metropolitan Life Insurance; 1937 Ideal weight for women. Statistical bulletin of the Metropolitan Life Insurance Company, 1943. Metropolitan Life Insurance Company. Ideal weights for men. Statistical Bulletin of the Metropolitan Life Insurance Company. 1942;23:6–8. Metropolitan Life Insurance Company. New weight standards for men and women. Statistical Bulletin-Metropolitan Life Insurance Company. 1959;40:1–4 Build and Blood Pressure Study. Vol. 1. Chicago, Ill, USA: Society of Actuaries; 1959 Build Study 1979. Chicago, Ill, USA: Society of Actuaries and Associations of Life Insurance Medical Directors; 1980 Metropolitan Life Insurance Company. Metropolitan height and weight tables. Statistical Bulletin (Metropolitan Life Insurance Company) 1983;64:1–19 Bray G., editor. Obesity in perspective. (DHEW Publication no (NIH) 75-708).Fogarty International Center. Series on Preventive Medicine. 1975;2(part 1) https://searchworks.stanford.edu/view/2520869