You're standing on a cold bathroom scale. The number flashes. You’re 5'8", which puts you in that "tall-ish" category for women where clothes fit well but finding jeans with the right inseam is a nightmare. But that number on the floor? It feels like a grade.
Most people want a magic number. They want to hear "145 pounds" and call it a day. Honestly, though, figuring out how much should a female weigh at 5 8 is way messier than a single digit. It’s about bone density. It’s about whether you lift weights or run marathons. It’s about your heritage.
Body mass index (BMI) is usually the first thing people look at. For a woman who is 5'8", the "normal" BMI range—which is a metric created in the 1830s by a Belgian mathematician named Adolphe Quetelet, not a doctor—is roughly 122 to 164 pounds. That is a massive 42-pound gap.
Forty-two pounds.
Think about that. Two women, both 5'8", could have a nearly 50-pound weight difference and both be considered "healthy" by medical standards. It's wild.
The BMI Trap and Why 5'8" is Unique
BMI is a blunt instrument. It doesn’t know if you’re carrying 20 pounds of muscle or 20 pounds of visceral fat. If you’re 5'8" and athletic, you might weigh 170 pounds and look lean because muscle is significantly denser than fat.
If we look at the Hamwi formula—a classic method used by dietitians to calculate "Ideal Body Weight" (IBW)—it starts with a base of 100 pounds for the first 5 feet of height and adds 5 pounds for every inch after that. For a 5'8" woman, that calculation looks like this: $100 + (8 \times 5) = 140$ pounds.
But wait.
The formula allows for a 10% adjustment based on "frame size." So, if you have a large frame (broad shoulders, wide hips), your "ideal" might actually be 154 pounds. If you have a petite, narrow frame, it might be 126.
Dr. Nick Fuller from the University of Sydney often points out that our bodies have a "set point" weight. This is the range where your body naturally wants to stay. If you force yourself down to 130 pounds just because a chart said so, but your body naturally cruises at 155, you’ll likely feel exhausted, cold, and hungry 24/7. That's not health; that's a prison sentence.
Muscle vs. Fat: The Density Debate
Let’s talk about volume. A pound of fat is roughly the size of a grapefruit. A pound of muscle is more like a tangerine.
When people ask how much should a female weigh at 5 8, they are usually asking "how do I look fit?" or "am I at risk for disease?" These are two very different questions. A woman who weighs 165 pounds but spends four days a week powerlifting will have a much lower body fat percentage and better metabolic markers than a woman who weighs 135 pounds but has very little muscle mass (often called "skinny fat").
The waist-to-hip ratio is actually a better predictor of health than the scale. For a woman, a ratio of 0.85 or lower is generally considered healthy. It tells us where the weight is. If your weight is 160 pounds but it’s mostly in your legs and hips, your cardiovascular risk is much lower than if that weight is concentrated around your midsection, near your organs.
Real World Examples: The 5'8" Spectrum
Look at professional athletes.
WNBA players are a great example of this height. Many of them are 5'8" or taller. A point guard at 5'8" might weigh 155 to 165 pounds. She’s pure muscle, explosive, and metabolically elite. Compare that to a high-fashion model of the same height, who might be pressured to stay around 115 or 120 pounds.
One of these women is fueled for performance; the other is likely under-fueling to meet an aesthetic standard.
The CDC's National Center for Health Statistics actually tracks the average weight of American women. For a woman around this height, the average weight has trended upward over the last few decades, now sitting closer to 170 pounds. While "average" doesn't always mean "optimal," it shows that the 125-pound ideal many women carry in their heads is increasingly disconnected from reality.
Frame Size: The Missing Variable
You can actually check your frame size right now. Wrap your thumb and middle finger around your opposite wrist.
- If they overlap, you have a small frame.
- If they just touch, you’re medium-boned.
- If there’s a gap, you have a large frame.
A large-framed woman at 5'8" will almost never feel or look "right" at 130 pounds. Her skeleton alone weighs more. She might have wider pelvic bones and a broader ribcage. For her, 160 or 170 pounds might be the "leanest" she can get without losing her period or hair.
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We also have to consider age. As women enter perimenopause and menopause, body composition shifts. Estrogen drops, and the body naturally tries to hold onto a bit more fat because adipose tissue (fat) actually produces a small amount of estrogen. A woman at 50 shouldn’t necessarily be aiming for the same weight she maintained at 22.
What Science Says About Longevity
Interestingly, some studies, including research published in the Journal of the American Medical Association (JAMA), suggest that being in the "overweight" BMI category (25 to 29.9) might actually be protective as we age. It’s called the "obesity paradox."
For a 5'8" woman, that "overweight" category starts at 165 pounds. If she gets a serious illness or needs surgery, having those extra reserves can actually improve survival rates.
Basically, being "too thin" is often more dangerous for long-term mortality than being slightly "heavy" by traditional standards.
Stop Obsessing and Start Measuring This Instead
If you want to know if your weight is "right," stop looking at the scale for a second.
Ask yourself these four questions:
- Do I have enough energy to get through my day without three cups of coffee?
- Is my sleep consistent and restorative?
- Am I strong enough to carry my own groceries or a 40-pound bag of dog food?
- Are my blood markers (A1C, cholesterol, blood pressure) in a healthy range?
If the answer is yes, then the number on the scale is almost irrelevant.
I’ve seen women at 5'8" who are 140 pounds and have high blood sugar because they eat mostly processed sugar and never move. I’ve seen women at 180 pounds who have perfect blood pressure and run 5Ks.
The Actionable Truth
You've got to find your "functional weight." This is the weight your body settles at when you are eating mostly whole foods, moving your body in a way you enjoy, and managing your stress.
If you’re trying to hit a specific goal for how much should a female weigh at 5 8, use these steps to find your unique healthy baseline:
Calculate your waist-to-height ratio. Keep your waist circumference to less than half your height. For a 5'8" woman (68 inches), your waist should ideally be under 34 inches. This is a much better health marker than total weight.
Prioritize protein and resistance training. Instead of trying to "lose weight," try to "change composition." Aim for 0.8 grams of protein per pound of target body weight. This protects your muscle mass, which keeps your metabolism firing.
Get a DEXA scan if you’re curious. If you really want the data, skip the $20 scale. A DEXA scan or a BodPod test will tell you exactly how many pounds of bone, muscle, and fat you have. It’s a reality check. You might find out you have "heavy bones" or high muscle mass, making that 165-pound number a badge of honor rather than a point of shame.
Ignore "goal weights" from middle school. Many women are chasing a number they saw on the scale when they were 17. Your adult body is different. Your hips have widened, your density has changed, and your life is different.
Check your labs. At the end of the day, your fasting insulin and your HDL/LDL ratios matter way more than your relationship with gravity. If your labs are clean, stop fighting your biology.
Ultimately, 5'8" is a height that allows for a lot of power and presence. Don't shrink yourself to fit into a box that was designed by a mathematician nearly 200 years ago who never met you.
Focus on Metabolic Health Over Scale Weight
The most important thing you can do right now is shift your focus from "weight loss" to "metabolic health." Start by tracking your morning fasting glucose or simply monitoring how your clothes fit. If your energy is high and your waist-to-height ratio is within a healthy range (under 0.5), you are likely exactly where you need to be, regardless of whether the scale says 140 or 170.