American women aged 20 years and above weigh an average of 168.5 pounds (lbs), according to the Centers for Disease Control and Prevention (CDC). Height-wise, the average adult female is 5 feet 4 inches, and her waist measures 38.1 inches.
While these numbers may be the average, they are not a measure of health. One of the commonly used indicators of well being is a person's BMI, which stands for body mass index.
The BMI of the average woman in the U.S. is 26.5, which falls into the category of "overweight." Out of all American adults, more than two-thirds are deemed to be "overweight" or "obese," which represents a worrying trend for the nation's health.
So, what is the ideal weight range for women, how is it best measured, and what can women do to achieve their ideal weight?
Average weight and obesity rates worldwide
A commonly used indicator for measuring well-being is BMI.
At 177.9 lbs, the average body mass in North America is the highest of any continent worldwide, according to 2005 statistics published in 2012 by BMC Public Health.
North America also has the highest percentage of people who are overweight, with 73.9 percent classed as such.
The following table shows the weight data for different world regions:
|Region||Average body mass (kg)||Percentage of people overweight|
|Asia||57.7 (127 lbs)||24.2|
|Europe||70.8 (156 lbs)||55.6|
|Africa||60.7 (133 lbs)||28.9|
|Latin America (Caribbean)||67.9 (149 lbs)||57.9|
|North America||80.7 (177 lbs)||73.9|
|Oceania||74.1 (163 lbs)||63.3|
|World||62.0 (136 lbs)||34.7|
In a 2015 review, the U.S. also had the highest rate of childhood obesity out of the world's 20 most populated countries, with a rate of 12.7 percent, although Egypt topped the table for adults at 35.3 percent.
What is the ideal weight range for women?
An "ideal weight" is where a person is at their healthiest and fittest in terms of what they weigh. There is a variety of different ways to calculate ideal weight ranges:
BMI is the most commonly used system for calculating ideal weight range, as it is relatively easy to work out. An individual can work out their BMI by applying their height and weight to the following formula:
- divide weight in kilograms by height in meters
- divide the answer by height again
For those people more familiar with using imperial measurements, there are various online calculators for working out BMI scores.
BMI calculations are the same for men and women, and BMI is seen as correlating fairly well with a person's percentage of body fat.
Despite this, BMI can give a false picture, as muscle weighs more than fat. Research in the journal Sports Health, showed athletes rating as "overweight" or "obese," despite being in peak condition.
One study also criticizes BMI for underestimating the prevalence of obesity in both sexes and being increasingly inaccurate as women age.
According to the National Heart, Lung, and Blood Institute, BMI ranges are as follows:
|Underweight||Less than 18.5|
|Obesity||30 or greater|
Waist circumference and hip-to-waist ratio
Fat is spread around a person's body but not all types of fat are equal.
The fat that can build up around someone's midsection and turn into a beer belly or love handles can indicate a higher risk for related diseases that have potential to do harm to your body.
Furthermore, it says calculating a person's waist-to-hip ratio is a better indicator of their fat distribution and disease implications than BMI is.
A person can work out their waist-to-hip ratio by dividing their waist measurement by their hip measurement.
Women should keep their waist circumference at 80 centimeters (cm) or 31.5 inches or less, according to the WHO. Anything more is associated with increased risk of related health problems, as follows:
|Indicator||Cut-off points||Risk of health problems|
|Waist circumference||More than 80 cm (31.5 inches)||Increased risk|
|Waist circumference||More than 88 cm (34.6 inches)||Substantially increased risk|
|Waist-to-hip ratio||Equal or more than 0.85||Substantially increased risk|
Body fat percentage
Body fat percentage is another way of calculating a person's ideal weight. Unlike BMI, it differentiates between how much of a person's weight is lean tissue and how much is fat.
In theory, body fat percentage is a good way of measuring ideal weight. However, in practice there are drawbacks:
- The most accurate ways of measuring body fat percentage, such as DXA scans (dual-energy X-ray absorptiometry), can be expensive and time-consuming.
- There is no set scientific agreement on what the ideal body fat percentages are or where the cut-off points should be.
Nonetheless, the American Council on Exercise propose the following body fat guidelines for women:
|Obesity||More than 32|
Weight and other factors
A woman's BMI and waist-to-hip ratio can help decide what is a healthy weight. But there are other factors to consider when finding what the ideal weight is for women.
Research shows that when people age, the amount of fat in their bodies increases while their muscle decreases. This means that people who want to stay lean may have to work harder on their diets and exercise when they get older compared to when they were younger.
Since BMI takes into account both height and weight, people who have the same BMI score but are of different heights will weigh different amounts.
Here's how a healthy BMI range translates to different weights at different heights:
|Height||Weight (BMI 19–24)|
Weight management tips
High-intensity interval training may be recommended to help manage weight.
Below are seven ways in which women can try to reach or maintain their ideal weight.
1. Do high-intensity interval training
High-intensity interval training (HIIT) involves circuits of exercises that use the maximum effort a person can manage. Each of these is followed by a cooldown period and then repeated.
Doing sprints in intervals is an example of HIIT.
Some research suggests that HIIT might fight fat in a variety of ways. It may also improve how the body handles blood glucose.
2. Cut out processed foods
As well as being less healthful than freshly prepared foods, processed foods are often laden with calories in the forms of sugar and fat. Cutting out all processed foods is a great way to reduce calorie intake.
3. Stay physically active
Staying active burns calories and positively alters a person's metabolism, helping them to maintain an ideal weight.
The U.S. government recommend that adults get 150 minutes of moderate exercise per week. This target might include brisk walking or playing tennis. Alternatively, they can chose 75 minutes of vigorous exercise every week, examples being jogging or continuous swimming.
4. Try intermittent fasting
Intermittent fasting means going for a time without food, and doing all your daily eating within a restricted time window, such as within 8 hours.
Some research has found that periodic fasting may help to promote greater overall fat loss.
5. Try a ketogenic diet
A ketogenic diet involves eating very few carbohydrates and a lot of fat.
Various studies show that a ketogenic diet may control hunger and cause the body to burn more fat than a standard diet.
6. Reduce your portion sizes
Reducing portion sizes is one of the easiest ways a person can consume less calories in a day. Simply eating off a smaller plate can do the trick.
7. Stay hydrated
Staying hydrated is essential for overall health and may help to stave off hunger pangs. Sometimes people can mix signals of thirst for those of hunger and have a snack when a glass of water would be satisfying.
There are many reasons why women might want to achieve their ideal weight, including personal beauty standards, athletic performance, and health.
Weight issues and obesity are significant problems in the U.S. Although not perfect, measures such BMI, waist circumference, and waist-to-hip ratio can help a woman better understand her weight.
If people feel their weight is a health risk, or they have worries, such as raised blood pressure, it may be a good idea to consult a doctor.
Moderate and intense exercise, portion control, and occasional fasting, among other things, can help encourage weight loss.