Body Mass Index

From WikiHow, you can calculate in pounds:

• Collect a few household materials to find your Body Mass Index (BMI): your bathroom scale; a yardstick; a pencil and paper and calculator.
• Weigh yourself on your clean bathroom scale.
• Measure your height in inches using the yardstick.
• Use the pencil, paper and calculator to perform the following BMI calculation:
  • Your height in inches and square the number (i.e. multiply the number of inches by the same number).
  • Divide your weight in pounds by the second figure (your height in inches squared).
  • Multiply that number by 703. The answer is your Body Mass Index.

Or you can let a BMI calculator do the math for you. You'll still need to know your precise height and weight, but you can use either English or Metric measurements in the calculator at the link to the Centers for Disease Control and Prevention's (CDC) BMI calculator, which is accessible by using the link further down this page. They have a calculator for adults and one for children and teens. Also see the related questions linked to this question for more information.

Note that BMI does not account for muscle mass. A short individual who has a large muscle mass may be considered obese by BMI calculations even though their body fat is low. Muscle weighs more than fat. Use the BMI as a guideline only, it is not health science.

For those who use metric units:

To figure out your BMI, take your weight (in kilograms) and divide it by your height (in meters). Now take that number and divide it by your height again. Now you have your BMI!

In a formula: BMI = weight (kg) / height2 (m)

For those who use imperial units:

To figure out your BMI, take your weight (in pounds) and divide it by your height (in inches). Now take that number and divide it by your height again. Once you have that answer, multiply that by 705, and you have your BMI!

In a formula: BMI = 705 * weight (lb) / height2 (in)

129 lbs and 5'5" gives a BMI of 21.47 which is normal.

The normal weight range of the given heigh is 111 - 150 lbs.

Please see the related link for the calculation.

Obesity clinically refers to being so overweight as to be detrimental to one's health. This can vary from individual to individual, depending on the height, muscle mass and body fat of that person. An individual who has a tall, muscular build and is 20 pounds overweight will probably not be considered obese (and actually may not be considered technically "overweight"), whereas a much shorter person with no muscle tone may well be obese if he or she packed on an extra 20 pounds.

Obesity is usually calculated by figuring one's Body Mass Index (BMI), which is determined by one's height and weight. Clinically speaking, it is usually determined that someone who has a BMI between 25 kg/m2and 30 kg/m2 is overweight while a person whose BMI is over 30 kg/m2 is obese. It should be noted, though, this is not always an accurate determination of who is obese and who is not as those with larger bone mass and more muscle mass will have a larger BMI. Still, I would recommend learning how to calculate your BMI is you would like to see where you fit in these statistics.

To Calculate BMI

To determine your BMI using inches and pounds, you simply divide your weight by your height2 (height in inches, squared), then multiply that number by 703.

For example, if you weigh 175 pounds, and are 5' 10" tall, your BMI would be 175/4900 x 703 = 25.11

While there can be an "average" weight (which, nowadays, may even be overweight), there is no ideal or perfect weight for a 12-year-old boy or girl or a person of any age. This is because weight is related to height and body composition rather than age. For more information, or to see the height/weight charts, or to learn about the causes of unwanted weight gain, see the page links, further down this page, listed under Related Questions.

Meanwhile, here are a selection of example answers from WikiAnswer users:

• I am 12 and I weigh 67 pounds. I am very athletic but very short. I am not unhealthy.
• I am 12-year-old and 6 foot. I weigh 198 pounds.
• I am 12 and 5' 4. I weigh 125 pounds.
• I am 4' 9" or 10" I weigh 90 pounds. I have bigger muscles than I did before but I am not very tall
• It does not it matter how much you weigh, what clothes you wear, or how big or small you are, if you happy with the weight, then it doesn't matter.
• I am 12. My height is 5' exactly and I weight 106 lbs.
• Everyone is beautiful in their own way. I am 12 and 8 months and I am 111 pounds and 5' 6."
• I am 12, 5' 5" and weigh 135 pounds.
• I'm 12 years old and I weigh about 125 pounds. I am 5' 4." It does not matter what you look like because there is always going to be someone out there who likes you for who you are.
• I am a 12-year-old boy. I am 5' 2" and I weigh about 120 pounds. I do kick boxing, judo, swimming, and boxing, so I have muscle.
• I'm 12 years old and im 5'4" and weight 145 lb not sure how much in kg
• I am a 12-year-old girl about 4' 11 or 5' 1. I am physically active, eat healthy, and weigh 100 lbs.
• I am 12 and weigh around 130 pounds i am about 5 feet tall

As said earlier, there is no ideal weight for 12-year-old because weight is related to height and body composition rather than age.

A person weighing in at about 150lbs. should take in around 55grams of protein a day
According to the Institute of medicine we need 0.8 grams of protein for every kilo of body weight.

Link attached for more info.

Some of the many increased serious health risks associated with obesity are:

1. Heart disease and heart attacks
2. Strokes and high blood pressure
3. Colon cancer (now associated with excess fat consumption in the diet)
4. Degenerative joint disease (arthritis), sometimes crippling and leading to a need for joint replacement
5. Insulin resistance
6. Diabetes mellitus (high blood sugars), with a long list of related complications in the circulatory (heart), renal (kidney), neurological (nerves), retinal (visual) systems and with infectious diseases and problems with healing
7. Depression (obese patients are typically inactive which can lead to increased incidences of chronic clinical depression that could be treated and greatly improved with exercise)
8. Bad self image
9. Negative thoughts
10. Breathing difficulties
11. Chronic fatigue

• Obesity can be very serious and even cause death. Pay attention especially if the weight is around your waist since it does affect heart and circulatory health to have it located there. Often obese people have high cholesterol and triglycerides, which can lead to strokes and heart attacks. Type II Diabetes and high blood pressure are additional risks. Obesity also affects mobility and ease of movement, which as you get older increases the risks of complications and falling.
• Eliminating or seriously limiting refined processed carbohydrates (apart from the occasional treat), coupled with cardio exercise, such as cardio walking, can help to reverse obesity. The diseases, often referred to as diseases of Western civilization, such as hypertension, heart disease, obesity, diabetes, dental caries, and others, became pervasive in the twentieth century primarily because of a diet high in refined carbohydrates. For example, from around two-and-one-half million years ago until the Agricultural Revolution around ten thousand years ago grains were not consumed by our ancestors. Many people have a problem with these foods because our bodies are extremely similar to the bodies of our hunter-gatherer ancestors. Less than 1/10th of 1% of our genes have changed in the last 10,000 years. It is not that long ago in terms of evolution. If you are unsure what refined processed carbohydrates are, you will find a list further down this page, listed under Related Questions.
• If you are significantly overweight, you need to avoid further weight gain and you need to lose weight. Excess body fat is a lot to carry and hard on your heart. Your lungs have to work harder, too.
• The correct weight for a person is related to BMI (body mass index). This can be measured for you. Alternatively, to determine your percentage of body fat at home, obtain some plastic body fat calipers and do a simple skin-fold test. Body fat calipers are not expensive and they are readily available to buy.
• See the Related Links section below for information about BMI and calculating your BMI from your height and weight using the Centers for Disease Control and Prevention (CDC) BMI calculators. BMI, Body Mass Index, can help you determine if you are considered overweight for your height and, if so, to what extent (e.g., underweight, normal weight, overweight, obesity, or morbid obesity.) There is also much more information about obesity in adults and children at that section of the CDC site.

BMI above 30 indicates obesity.

BMI between 25 and 30 indicates overweight.

BMI below 25 is desirable for most people.

Please note that BMI is a fairly limited tool and should not be used as an exclusive means to diagnose obesity.

People can become obese from many causes:

• Overeating and not burning off the calories consumed
• Sleep Apnea
• Genetic Disposition
• Diseases and Conditions that contribute to obesity (Cushing's Disease)
• Hormonal Dysfunction (Adrenal Glands, Thyroid, etc)
• Disability (unable to exercise)
• Eating Disorder
• Cardiovascular or Respiratory Disorder
• Injury