For a 5’7″ woman, a healthy weight falls between roughly 118 and 159 pounds based on standard BMI guidelines. That range corresponds to a BMI of 18.5 to 24.9, which the CDC classifies as “healthy weight.” But a single number on the scale tells an incomplete story. Where your body carries weight, how much of it is muscle versus fat, and your age all influence what “ideal” actually means for you.
The Standard BMI Range
BMI, or body mass index, is a simple ratio of weight to height. For a 5’7″ woman, the math breaks down like this:
- Underweight: below 118 pounds (BMI under 18.5)
- Healthy weight: 118 to 159 pounds (BMI 18.5 to 24.9)
- Overweight: 160 to 190 pounds (BMI 25 to 29.9)
- Obese: above 191 pounds (BMI 30 or higher)
That healthy range spans over 40 pounds, which is intentional. Two women at the same height can weigh very differently and both be perfectly healthy, depending on their frame size, muscle mass, and body composition.
What Clinical Formulas Suggest
Doctors have historically used shorthand formulas to estimate an “ideal” body weight for medication dosing and clinical assessments. The most common one for women, the Hamwi formula, starts at 100 pounds for the first 5 feet of height and adds 5 pounds per additional inch. For a 5’7″ woman, that produces 135 pounds. Other clinical formulas land in a similar neighborhood, generally between 130 and 140 pounds.
These formulas were never designed to tell you what you should weigh for optimal health. They were created decades ago as rough clinical tools and don’t account for body composition, ethnicity, or fitness level. Think of them as a midpoint estimate, not a personal target.
Why BMI Misses the Full Picture
BMI treats all weight the same, whether it comes from muscle, bone, or fat. A 5’7″ woman who strength trains regularly might weigh 155 pounds with a low body fat percentage and excellent metabolic health, while another woman at the same weight could carry significantly more fat and face higher health risks.
Body fat percentage gives a more accurate read. For women, health organizations generally consider anything above 30 to 35 percent body fat to indicate excess fat, regardless of what the scale says. Fit or athletic women typically fall between 14 and 24 percent body fat. Research from the AMA Journal of Ethics found that women in the highest third of body fat (above 33 percent) were seven times more likely to have metabolic syndrome, a cluster of risk factors including high blood sugar, high blood pressure, and abnormal cholesterol, even when their BMI looked normal.
This condition, sometimes called “normal weight obesity,” is why stepping on a scale alone can be misleading. You can have a BMI of 22 and still carry enough visceral fat to raise your disease risk.
Waist Size as a Better Risk Indicator
One of the simplest ways to gauge whether your weight is in a healthy range is to measure your waist. The NHS recommends keeping your waist circumference below half your height. For a 5’7″ woman (67 inches tall), that means a waist measurement under 33.5 inches.
The American Heart Association flags a waist circumference above 35 inches (88 cm) in women as a marker for significantly elevated disease risk, particularly for type 2 diabetes and cardiovascular disease. At that threshold, even women in the “overweight” BMI category jump from increased risk to high risk. A tape measure around your midsection, taken at the level of your navel, can tell you more about metabolic health than a bathroom scale.
How Weight Risks Change at Different Points
Health risks don’t suddenly spike the moment you cross from 159 to 160 pounds. But the data does show a clear gradient. In a large study of women aged 30 to 55, those with a BMI of just 25 to 26 (around 160 to 166 pounds at 5’7″) had 2.5 times the risk of developing high blood pressure compared to women with a BMI under 20. At a BMI of 28 to 31, that risk jumped to over 4 times higher.
Heart disease risk follows a similar pattern. Women with a BMI in the 27.5 to 29 range (roughly 175 to 185 pounds at 5’7″) showed 1.4 to 2.8 times the risk of cardiovascular death over follow-up periods of 10 to 26 years. Type 2 diabetes risk is especially sensitive to weight, rising significantly even within the overweight category before reaching obesity.
How Age and Menopause Shift the Numbers
Body composition changes naturally with age, especially around menopause. As estrogen levels drop, women tend to gain fat in the midsection, even without gaining total weight. This shift matters because abdominal fat is more metabolically active and more closely linked to heart disease and diabetes than fat stored in the hips or thighs.
Research published in the Journal of Menopausal Medicine found that BMI becomes a less accurate proxy for body fat after menopause. In premenopausal women, a BMI of about 29.5 corresponded to a high body fat threshold. In postmenopausal women, that same level of body fat showed up at a BMI of roughly 26.5. In practical terms, a postmenopausal woman at 5’7″ and 170 pounds may carry a similar metabolic risk as a younger woman at a higher weight. This doesn’t mean the healthy range shrinks with age; it means the same BMI number can mean different things at different life stages.
For women over 50, paying closer attention to waist circumference and body fat percentage, rather than fixating on a scale number, gives a more honest assessment of health.
Finding Your Personal Target
Rather than chasing a single number, it helps to think of your ideal weight as a zone defined by several markers working together:
- Scale weight: 118 to 159 pounds puts you in the standard healthy BMI range at 5’7″
- Waist circumference: under 33.5 inches (half your height), and ideally well under 35 inches
- Body fat percentage: below 30 to 35 percent for general health, or 14 to 24 percent if you’re athletic
- Metabolic markers: normal blood pressure, blood sugar, and cholesterol levels
A woman at 145 pounds with a 30-inch waist and normal blood work is in a very different position than a woman at 145 pounds with a 36-inch waist and prediabetic blood sugar, even though they’d have the same BMI. The number on the scale is a starting point, not the whole answer. Where you carry your weight and what that weight is made of are what ultimately determine your health risk.