The notion that an ideal weight exists for every age and gender fails to take into account differences in body fat percentage, height and body shape. An ideal weight for your age really isn't relevant unless you're measuring growth rates of a child. The body mass index, or BMI, helps give you an idea of how your height relates to your weight and whether you fall into a "normal" range, but BMI is a crude measure that doesn't always give you an accurate picture of health either.
If you're concerned about your size, your healthcare provider can help you determine if are at an unhealthy weight. Ultimately, worry about your health and how you feel, instead of achieving a subjective number on the scale.
BMI Uses Weight and Height, Not Age and Gender
An "ideal" weight that's aesthetically pleasing is open to personal interpretation, but one that promotes good health can be better defined. Medical providers evaluate your size according to body mass index, which is a calculation that measures the relationship between your height and weight, regardless of gender. BMI provides a rough estimation of your body fat and gauges your risk of disease. A high BMI indicates you're overweight or obese and thus at a greater risk of heart disease, high blood pressure, type 2 diabetes and certain cancers.
A BMI of 18.5 to 24.9 is considered normal, 25 to 29.9 is overweight, and 30 or higher is obese. People who are 5 feet tall and weigh between 97 and 127 pounds; 5 feet, 5 inches, weighing 114 to 149; 6 feet, weighing 140 to 183; and 6 feet, 4 inches, weighing 156 to 204, all fall within the normal, healthy BMI range. Because men are usually larger and more muscular than women, they're usually on the higher end of the weight range for any height.
If you're wondering about a child's growth pattern, have his height and weight measured at a doctor's office and talk to a healthcare provider about how he falls within the norm.
Measuring your weight using BMI may miscategorize some people as overweight and others as healthy. Athletic people with a lot of muscle mass may be quite lean and healthy, but because they weigh a lot for their height, the formula finds them overweight or even obese. For others, BMI fails to specify how fat is distributed in the body and misses those with "normal weight obesity." People with this condition fall within a healthy BMI range according to their weight and height, but have a high body fat percentage. Fat in excess of 30 percent for women and 20 percent for men -- particularly in the belly -- puts otherwise normal weight people at risk of the chronic conditions associated with obesity, such as high blood pressure and type 2 diabetes.
Body Fat Levels
Two people may weigh the same, but the weight looks entirely different due to their individual body shape. Ectomorphs tend to be long and lean; endomorphs often gain fat easily and are more pear-shaped; while mesomorphs boast muscular, athletic builds. You're born with your body type, and no one is "ideal," as long as you're within a healthy weight range.
An "ideal" weight might be one that has a higher percentage of lean mass which gives the appearance of tone and shape. No hard and fast guidelines for healthy body fat levels exist as they do for BMI, but according to the American Council on Exercise, a "fit" person usually falls between 21 and 24 percent body fat for a woman and 14 to 17 percent for men. Athletes tend to have even lower body fat levels: between 14 and 20 percent for women and 6 to 13 percent for men. The average person falls between 25 and 31 percent for women and 18 and 24 percent for men. Being average doesn't necessarily indicate a healthy fat range, however.
Let Go of Perfect Weight Ideals
Your weight fluctuates by several pounds daily, depending on what you've eaten, your hormones and water retention. Even if you achieve an "ideal" weight in the morning, it may fall out of that ideal range several hours later after breakfast and lunch, when food and water have increased your weight. Of course it's important to be within a healthy weight range to keep your risk of disease low, but where you fall exactly within that range is less important.
Use your lifestyle habits as a better measure of your health. Eat a healthy, portion-controlled diet consisting mostly of whole, unprocessed foods; exercise at least 150 minutes per week at a moderate intensity; get seven to nine hours of sleep per night; and avoid excesses of alcohol, tobacco and drugs. An ideal lifestyle is far most important for your long-term weight and health.