BMI: measuring height, weight, waist circumference Flashcards
What is BMI, what is the formula and what does a patient’s BMI value indicate?
Body Mass Index
Weight in Kg/height in m2, BMI value is given to 1 d.p
BMI is an estimate of body fat
What are the 4 categories of BMI values?
Underweight (less than 18.5)
Healthy weight (18.5-24.9)
Overweight (25.0-29.9)
Obese (30.0 or higher)
Does BMI consider the difference between muscle and fat?
No, this is why a muscular patient may be categorised as overweight or obese even though they have low body fat
What is the correlation between BMI value and likelihood of developing certain health conditions?
Higher your BMI, the more likely your risk of developing diseases that can occur with more body fat
eg. Type 2 diabetes, heart disease, high bp, gallstones
What personal detail other than height and weight is used to calculate BMI and why?
Ethnic background
Asian, Black African, African-Caribbean, Middle Eastern background cause higher risk of developing health conditions at lower BMI
What 4 ethnic groups have higher risk of developing health conditions that occur from more body fat, at a lower BMI?
Asian
Black African
African Caribbean
Middle Eastern
Why can it be useful to measure waist circumference after calculating BMI?
Waist circumference provides better estimate of visceral fat (fat that coats organs)
People who have most of their body fat near waist instead of hips are more likely to develop type 2 diabetes and heart disease
Which 4 categories of patients shouldn’t use the BMI tool for adults?
Under 18 years old
Pregnant
Diagnosed with eating disorder, or thinks they might have one
Have condition that affects height
What 4 steps are needed to measure a patient’s height?
Ask patient to take shoes off and stand on stadiometer
Ask patient to stand straight and ensure this by checking that back of head, shoulder blades, buttocks, heels touch stadiometer
Ask patient to look straight ahead and keep chin down
Bring headplate down to top of patient’s head
What device is used to measure height?
Stadiometer
What 3 steps are needed to measure a patient’s weight?
Calibrate scale so that it is at 0kg
Ask patient to take off shoes, jacket, remove things from pockets
Ask patient to step onto scale and look straight ahead
What 3 steps are needed to measure waist circumference?
Wrap tape measure around patient, just above hip bones and in line with belly button and ensure that it is horizontal
Keep tape snug around waist but don’t compress skin
Make sure that tape measure ends meet at patient’s side (not front or behind) as this is more comfortable for the patient
What could a low BMI indicate?
Malnutrition, could be due to unbalanced diet or disease that affects nutrient absorption
