BMI (Body Mass Index) is fast a method of assessing person's weight. It uses very simple mathematical formula to calculate it: body weight (in pounds/kilograms) devided by height (in inches/meters) squared (BMI = weight/height2)
BMI for people who are muscular or atheletic will show that they are obese, which is untruth. It should also not be used for children or pregnant women.
As this is a mathematical formula only, BMI calculation method for men and women is the same. Experts say that it may seem incorrect but health risks for Diabetes and Cardiovascular Disease increase at similar BMI for both genders.
Despite health related risk, visual interpretation may be different for women and men.
Most of women feel that they look most attractive when their BMI values are between 20 - 22, whereas men are usually satisfied with a BMI value of 23 - 25. Having BMI between 17 - 22 means that your life expectancy should longer than average. Your weight is perfect.
If case your BMI is between 23 - 25, you are considered by most of people as a healthy looking person. If your BMI index exceed 26 or more, that is not good. You should be more cautious when choosing meal and contact your doctor for further guidance.
Despite it all just be happy and enjoy your life :) Remember that the concept of beauty is subjective and a perfect body image do not exist in real life, it's a creation of media.Trust judgment of yours, your family and friends and don't get too anxious about your apperance. Mental health is as important as physical fitness!