How Much Should I Weigh?

Pretty much everyone has, at some point or another, attempted to shed some pounds, or at the very least, has known someone who has. This is largely due to the concept of a so-called “perfect” body weight, which has traditionally been set by what we see pushed through social media, television, cinema, magazines, etc. Despite the idea of the ideal body weight (IBW) being sometimes calculated according to how appealing a hypothetical figure appears to oneself or others, IBW was introduced to calculate dosages for medical purposes, and the formulas that calculate it all not connected with a person’s appearance at any weight. More recently, it has been found that the metabolism of some drugs is more dependent on IBW than total body weight. Today, IBW has a far wider scope of application throughout sports, since many sports categorize people based on body weight.

Disclaimer: IBW is not an exact measurement. Neither does it take into account the ratios of fat and muscle in a body. In other words, a very fit, healthy athlete could be found to be overweight when IBW is calculated. This is the perspective with which IBW should be approached because it is an impermanent measure that is not necessarily representative of health, nor a want that you should necessarily be working toward; you can be over or under your “IBW” and be perfectly okay.

There is no exact scientific answer to how much a person should weigh. It depends on the person. We do not yet possess a standard—be it IBW, BMI, or something else entirely—that will tell us in absolute terms how heavy a given person should be to be healthy. They are just guides, and we really should be focused on making healthy life choices (exercising regularly, consuming mainly unprocessed foods, good sleep, etc.) rather than trying to reach a certain number on a scale based on an average calculation.

Several factors affect the ideal weight, as follows; however, this can vary for different reasons. Other factors are the status of health, the distribution of fat, offspring, etc.

Age

Since most people stop growing around the ages of 14-15 for girls and 16-17 for boys, theoretically, age shouldn’t be a major factor affecting an IBW. Indeed, by age 70, it is anticipated that human men and women should be decreasing in height by an inch or so (the average 1.5 and 2 inches, respectively). Just bear in mind that as we get older, we lose lean muscle and we are more likely to hang on to excess body fat. It is a natural process, but it can be mitigated by a healthier lifestyle with proper nutrition, exercise, stress management, and sleep management.

Gender

Females tend to be lighter than males at the same stage of development , although they have a naturally higher percentage of body fat. The male percentages are typically higher for muscle mass, and as we know, muscle is denser than fat, so it weighs more. Also, bones are usually less dense in women. Finally, males are generally taller than females.

Height

There is just more person; more muscle mass, more body fat, the higher the letter, the more weight packed tightly into a frame. All other things being equal, a male at the same height as a female should weigh 10-20% more.

Body Frame Size

Another factor that could make the ideal weight differ is the body frame size. Typically, body frame size is categorized into either small, medium or large boned. which is based on the ratio between the circumference of a person wrist and their height, see below.

For women:

• Height under 5’2″
  • Small boned = wrist size less than 5.5″
  • Medium boned = wrist size 5.5″ to 5.75″
  • Large boned = wrist size over 5.75″
• Height between 5’2″ and 5′ 5″
  • Small boned = wrist size less than 6″
  • Medium boned = wrist size 6″ to 6.25″
  • Large boned = wrist size over 6.25″
• Height over 5′ 5″
  • Small boned = wrist size less than 6.25″
  • Medium boned = wrist size 6.25″ to 6.5″
  • Large boned = wrist size over 6.5″

For men:

• Height over 5′ 5″
  • Small boned = wrist size 5.5″ to 6.5″
  • Medium boned = wrist size 6.5″ to 7.5″
  • Large boned = wrist size over 7.5″

A person who is large boned will eat more than a person who is small boned, even at the same height, so body frame size can influence measures such as IBW or BMI.

Equations for Calculating Ideal Body Weight

The origin of IBW formulas was in the practical need to calculate drug dosages. All formulas share the same base weight for a 5-foot height, plus an incremental weight per inch above 5 feet. Say you are a 5’10” male calculating your ideal weight with the Devine formula, you would add (2.3 × 10) kg to 50 kg to reach 73 kg (~161 lbs).

These formulas incorporate different values according to the research of the scientists who developed them and the outcomes of their research. Although there are several IBW measurement formulas available, the Devine formula is the one that is most frequently utilized.

G. J. Hamwi Formula (1964)

Male:	48.0 kg + 2.7 kg per inch over 5 feet
Female:	45.5 kg + 2.2 kg per inch over 5 feet

Invented for medicinal dosage purposes.

B. J. Devine Formula (1974)

Male:	50.0 kg + 2.3 kg per inch over 5 feet
Female:	45.5 kg + 2.3 kg per inch over 5 feet

Like the Hamwi Formula, it was originally designed as a starting place for drug dosages based on weight and height. As the years passed, the equation became a standard means of assessing IBW.

J. D. Robinson Formula (1983)

Male:	52 kg + 1.9 kg per inch over 5 feet
Female:	49 kg + 1.7 kg per inch over 5 feet

Adjusted Devine Formula.

D. R. Miller Formula (1983)

Male:	56.2 kg + 1.41 kg per inch over 5 feet
Female:	53.1 kg + 1.36 kg per inch over 5 feet

Modification of the Devine Formula.

Healthy BMI Range

According to the World Health Organisation (WHO), a healthy BMI for both males and females is 18.5 – 25. You can discover a healthy range of weights for any height based on the BMI.

It is an index of body fat and is widely used to determine IBW. In the medical field, it is commonly used as a fast assessment of the possible health consequences. More often than not, the greater the BMI, the greater the risk that the affected will develop related health issues like obesity, diabetes, heart disease, and the like. Currently, the official standard used by doctors to classify their patients into various stages of obesity, as well as to warn them of possible health problems (especially if the BMI is becoming progressively higher).

Children’s Healthy BMI Range

The above formulas apply to adults 18 years of age or older. See the following BMI charts from the Centers for Disease Control and Prevention (CDC) for children and teens. According to CDC guidelines, children should have a BMI between the 5th and 85th percentile for their age.

1. BMI chart for boys aged between 2 and 20
2. BMI chart for girls aged between 2 and 20

IBW Calculator Limitations

All the formulae and methods have their limitations. Formulas are made to apply to as large a population of individuals as they can, meaning that they cannot be extremely precise for every single individual. The formulas take only height and gender into account, with no allowance for physical handicaps, those at extreme ends of the spectrum, muscle mass, body fat ratio (body composition), and activity levels. The Ideal Weight Calculator is only an indicative tool based on the most common formulas; the values delivered by it should not be understood as absolute values that you have to achieve or not to be considered an “ideal weight”.