What is the method for calculating ideal body weight (IBW)?

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Last updated: May 7, 2025View editorial policy

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From the Guidelines

To calculate ideal weight, the most recent and highest quality study recommends using the modified Devine’s formula, where ideal body weight for men is 51.65 kg + 1.85 kg/inch of height > 5 feet, and for women, it is 48.67 kg + 1.65 kg/inch of height > 5 feet, as stated in the 2024 study by the European Society of Cardiology 1.

Calculating Ideal Weight

There are several methods to calculate ideal weight, but the most commonly used is the Body Mass Index (BMI) method.

  • BMI is calculated as weight in kilograms divided by height in meters squared (kg/m2).
  • For adults, a BMI between 18.5 and 24.9 is considered healthy.
  • The modified Devine’s formula provides a more accurate estimate of ideal body weight, taking into account height and gender.

Limitations of BMI

While BMI is a widely used measure, it has limitations, as it does not distinguish between lean and fat mass.

  • Individuals with high levels of lean body mass may be misclassified as overweight or obese.
  • Conversely, adults with normal weight but excess body fat may not be diagnosed as overweight or obese.

Importance of Consulting a Healthcare Provider

It is essential to consult with a healthcare provider to determine the healthiest weight for an individual, as age, activity level, and medical conditions can influence this.

  • Overall health markers, such as blood pressure, cholesterol levels, and energy levels, should be considered when determining ideal weight.
  • A healthcare provider can provide personalized guidance and help individuals set realistic and achievable weight goals.

From the Research

Calculating Ideal Weight

To calculate ideal weight, several factors need to be considered, including body mass index (BMI), waist circumference, and other health indicators.

  • BMI is a commonly used measurement to determine whether a person is at a healthy weight, and it is calculated by dividing weight in kilograms by height in meters squared 2, 3, 4, 5, 6.
  • According to the studies, BMI is strongly associated with various health risks, including high blood pressure, glucose, and lipid levels 2, 3, 4, 5, 6.
  • Waist circumference is also an important factor, as it is associated with an increased risk of chronic diseases such as diabetes and cardiovascular disease 4, 6.
  • The ideal weight can be calculated using the BMI formula, with a healthy BMI ranging from 18.5 to 24.9 2, 3, 4, 5, 6.

Factors Affecting Ideal Weight

Several factors can affect a person's ideal weight, including:

  • Age: As people age, their body composition and metabolism change, which can affect their ideal weight 4.
  • Sex: Men and women have different body compositions and health risks, which can affect their ideal weight 3, 4, 5, 6.
  • Ethnicity: Different ethnic groups may have different body compositions and health risks, which can affect their ideal weight 5.
  • Lifestyle: A person's diet, physical activity level, and other lifestyle factors can affect their ideal weight 2, 3, 4, 5, 6.

Health Risks Associated with Excess Weight

Excess weight is associated with various health risks, including:

  • High blood pressure: Excess weight can increase blood pressure, which can lead to cardiovascular disease 2, 3, 4, 5, 6.
  • High glucose levels: Excess weight can increase glucose levels, which can lead to diabetes 3, 4, 5.
  • High lipid levels: Excess weight can increase lipid levels, which can lead to cardiovascular disease 2, 3, 4, 5, 6.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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