You're standing on the scale. It's 7:00 AM. You look at the number, then you look at your height—5 feet 9 inches—and you wonder if those two figures actually get along. Most people just Google a chart, see a range, and either sigh in relief or start panicking about their dinner plans. But honestly, the question of how much should a 5'9 person weigh is way more complicated than a single number on a digital screen.
Bodies are weird.
Two people can both stand 5'9" and look entirely different despite weighing the exact same amount. One might be a marathon runner with a lean frame, while the other is a powerlifter with thighs like tree trunks. If you go strictly by the book, the medical community usually points toward the Body Mass Index (BMI). For a 5'9" adult, the "normal" weight range is typically cited as being between 125 and 168 pounds.
That’s a huge gap. Over forty pounds.
The BMI Problem and Why It’s Only Half the Story
We have to talk about the BMI. It was created in the 1830s by a Belgian polymath named Lambert Adolphe Jacques Quetelet. He wasn't even a doctor; he was a mathematician. He wanted to find the "average man," not necessarily the "healthiest man." Fast forward nearly 200 years, and we're still using his math to decide if we're "overweight."
If you’re 5'9" and weigh 175 pounds, the BMI says you’re overweight. But what if you’ve been hitting the gym five days a week? Muscle is dense. It takes up less space than fat but weighs a ton more. If you have a high muscle mass, that 175 pounds might look incredibly lean, while someone at 150 pounds with very little muscle might actually carry more internal health risks.
This is what doctors call "normal weight obesity" or, more colloquially, "skinny fat." You fall into the "ideal" range for your height, but your body fat percentage is high enough to put you at risk for Type 2 diabetes or heart issues. So, the number is just a data point. It’s not the whole story.
💡 You might also like: Can DayQuil Be Taken At Night: What Happens If You Skip NyQuil
Frame Size Matters Way More Than You Think
Have you ever looked at your wrists? It sounds silly, but frame size is a real physiological factor. Anthropologists and health experts often categorize people into small, medium, or large frames.
If you have a "large frame" at 5'9", your bones are literally heavier and your torso is likely wider. For a man with a large frame at this height, the Metropolitan Life Insurance Company’s legacy weight tables—which many experts still prefer over raw BMI—suggest a healthy range could actually top out around 176 or 180 pounds. Conversely, a small-framed woman who is 5'9" might feel and look her best at the lower end of the spectrum, perhaps 135 to 145 pounds.
To find your frame size, you can wrap your thumb and middle finger around your wrist. If they overlap, you're likely small-framed. If they just touch, you're medium. If there's a gap? You've got a large frame. It’s a lo-fi test, sure, but it’s a better indicator of where your "set point" might be than a generic internet calculator.
Let's Look at the Data: Men vs. Women
Biology plays a role here, too. Generally speaking, men at 5'9" carry more bone density and muscle mass than women of the same height.
For men, a "healthy" weight is often pinned between 144 and 176 pounds. Most 5'9" men find that they feel strongest and most energetic when they hover around 160. Once you dip below 140, you might start losing significant muscle tone. If you're pushing 190, even if it's muscle, you're putting a lot of strain on your joints.
For women, the 5'9" height is actually quite tall—well above the national average of 5'4". Because women naturally have a higher body fat percentage for reproductive health, the "ideal" weight is often seen as 128 to 162 pounds. Many female athletes at this height will sit comfortably at 155 pounds, while a fashion model of the same height might be pressured to stay under 125—a weight that many doctors would consider borderline underweight and potentially disruptive to hormonal balance.
📖 Related: Nuts Are Keto Friendly (Usually), But These 3 Mistakes Will Kick You Out Of Ketosis
What About Age?
We can't ignore the "middle-age spread." It’s a real thing, and maybe it’s not as bad as we thought.
Research, including studies published in the Journal of the American Geriatrics Society, suggests that as we age, carrying a few extra pounds might actually be protective. For someone who is 65 years old and 5'9", being at the higher end of the BMI—say, 170 or 175 pounds—can provide a "buffer" against frailty and bone loss if they happen to get sick. The obsession with being as thin as possible is mostly a young person's game. As you get older, the focus should shift from the scale to "functional mass." Can you still carry your groceries? Can you get up off the floor without help?
Beyond the Scale: The Metrics That Actually Count
If the scale is a liar, or at least a storyteller who leaves out the best parts, what should you actually track?
Waist-to-Hip Ratio: This is a huge one. Take a measuring tape. Measure the smallest part of your waist and the widest part of your hips. Divide the waist by the hips. If you're a man and the number is over 0.90, or a woman and it’s over 0.85, you’re carrying "visceral fat." That’s the dangerous stuff around your organs. You could be 150 pounds and 5'9", but if all that weight is in your belly, you’re at higher risk than a 180-pound person with a flat stomach.
Blood Pressure and Lab Work: Honestly, if your blood pressure is 120/80, your resting heart rate is in the 60s, and your A1C is stable, who cares if you weigh 172 instead of 162? Metabolic health is the king of all metrics.
Energy Levels: Do you crash at 2 PM? Can you walk up three flights of stairs without feeling like your lungs are on fire? Physical capability is a much better "health" metric than how you look in a pair of Levi's.
👉 See also: That Time a Doctor With Measles Treating Kids Sparked a Massive Health Crisis
The Professional Perspective
Dr. Nick Fuller from the University of Sydney has spent years researching "interval weight loss" and the body’s "set point." His work suggests that our bodies have a weight they want to be at. If you’re 5'9" and your body naturally hovers at 165 pounds, fighting to get down to 145 will be a constant, miserable war against your own biology. Your metabolism will slow down, your hunger hormones (like ghrelin) will spike, and you'll eventually gain it all back.
The "should" in "how much should I weigh" should be defined by your body's equilibrium, not a chart in a doctor's office that hasn't been updated since the VHS era.
Real-World Examples
Think about professional athletes. A 5'9" CrossFit athlete like Mat Fraser (who is actually a bit shorter, but the principle applies) weighs around 190 pounds of pure muscle. By BMI standards, he’s "obese." That’s obviously ridiculous.
On the flip side, look at a distance runner. They might be 5'9" and 130 pounds. They aren't "too thin"; they are optimized for their sport.
Most of us aren't pro athletes. We're just people trying to live. If you’re 5'9", and you’re eating whole foods, moving your body, and sleeping well, your weight will likely settle into a 10-pound "happy range." For most, that’s somewhere between 150 and 170 pounds.
Actionable Steps to Finding Your Target Weight
Stop chasing a "perfect" number. It doesn't exist. Instead, follow these steps to figure out where your body actually functions best:
- Ditch the daily weigh-in. Weight fluctuates by 3-5 pounds a day based on salt, water, and stress. Weigh yourself once a week, or better yet, once a month.
- Get a DEXA scan or use bioelectrical impedance scales. These aren't perfect, but they give you a rough idea of your body fat percentage vs. muscle mass. For a 5'9" man, 15-20% body fat is a great target. For a woman, 22-28% is generally very healthy.
- Focus on protein intake. Aim for about 0.7 to 1 gram of protein per pound of target body weight. This helps preserve muscle, which keeps your metabolism firing regardless of your total weight.
- Measure your waist. Keep that waist circumference under 35 inches for women and 40 inches for men to minimize metabolic disease risk.
- Assess your "Set Point." Note the weight you return to when you aren't dieting but aren't overeating. That is likely your biological "should" weight. Work with it, not against it.
The reality of how much a 5'9" person should weigh is that health is a feeling, not a digit. If you can move well, your blood work is clean, and you feel comfortable in your skin, you've already found the right answer.