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How much should I weigh?

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Health dangers due to obesity

These dangers are associated with overweight and obese adults

Adults with a BMI of greater than 25 (overweight) or whose BMI is greater than 30 (obese) have an increased risk for a number of diseases and health conditions, including,:

BMI Prime

Devised all the way back in way back in 1830, the b.m.i. is a single figure used to as a way of measuring a person's body shape. Put simply, it is calculated by dividing the body's weight by the square of their height. Eg: Kilograms: weight, divided by Metres (Meters): height. b m i Prime is a variation of the Quetelet index. Put simply, if you have a Prime of less than 0.74, you are underweight. If your prime is more than 0.74 and less than 1.00, your weight is ideal. If your bmi prime is more than 1 you are defined as being overweight.

How it's calculated

How Body Mass Index is worked out
  • BMI = weight(kilograms) / height2 (metres2)         (Metric Units)
  • BMI = 703 . weight(pounds) / height2 (inches2)         (Imperial Units)

BMI limitations

BMI is particularly inaccurate for people who are very fit or athletic, as their high muscle mass can classify them in the overweight category by BMI, even though their body fat percentages frequently fall in the 10-15% category, which is below that of a more sedentary person of average build who has a normal BMI number.
See wikipedia.org/wiki/Body_mass_index#Limitations for further clarification.