For someone who stands 5’8″, the conventional “healthy” weight range based on standard guidelines falls between roughly 125 and 163 pounds, but that window shifts depending on your age, sex, and skeletal frame. A BMI of about 22, which research links to the lowest mortality risk in younger and middle-aged adults, works out to around 145 pounds at this height. That number, though, is a starting point rather than a verdict, because what counts as a healthy weight for a 25-year-old with a narrow frame and what counts as healthy for a 70-year-old with broad shoulders and thick wrists are genuinely different questions with different answers.
The Standard Range and Where It Comes From
Most weight recommendations for a given height are derived from body mass index, which divides weight by the square of height. At 5’8″, a BMI between 18.5 and 24.9 translates to about 122 to 164 pounds. The midpoint of that range, a BMI of 22, sits at roughly 145 pounds and has historically been associated with the lowest all-cause mortality in the general adult population. A comparison of the major ideal-body-weight formulas and published height-weight tables found that most of them predict weights that fall within the BMI 20 to 25 range, though formulas for taller people tend to land closer to BMI 25 and formulas for shorter people lean toward BMI 20.1PubMed. Comparison of ideal body weight equations and published height-weight tables with body mass index tables for healthy adults in the United States That same analysis noted that no single formula worked well for predicting the “ideal” weight for women, suggesting that BMI ranges are more practical than any single formula for either sex.
So if you are a generally healthy adult in your twenties or thirties at 5’8″, a weight somewhere in the neighborhood of 130 to 160 pounds puts you solidly within the conventionally healthy zone. But that 40-pound spread is wide for a reason: it exists to accommodate differences in muscle mass, bone density, fat distribution, and frame size. Two people can stand at the same height, weigh the same amount, and carry very different amounts of body fat.
How Age Changes the Picture
The “ideal” weight at 5’8″ is not the same at 30 as it is at 65. Bodies change with age in ways that shift both what you’re likely to weigh and what weight is actually healthy. During normal aging, muscle mass decreases while fat mass increases, a process that accelerates after midlife.2PubMed Central. Sarcopenic obesity and endocrinal adaptation with age This means an older adult at the same weight as their younger self may have less muscle and more fat, especially around the midsection.
Large studies tracking weight over decades show that most adults gain a meaningful amount of weight between early adulthood and middle age. In one analysis, women gained an average of about 28 pounds over 37 years of follow-up, while men gained roughly 21 pounds over 34 years.3PubMed Central. Associations of Weight Gain From Early to Middle Adulthood With Major Health Outcomes Later in Life That weight gain tends to accelerate in middle age: data tracking adults over successive six-year periods found that the rate of BMI increase sped up with each period, especially among people who started in the normal-weight or overweight categories.4PubMed Central. Patterns of Weight Gain in Middle-Aged and Older US Adults, 1992–2010
Here is where the evidence gets genuinely interesting and counterintuitive: for older adults, the healthiest BMI is higher than for younger people. A meta-analysis of studies in older adults found that the lowest mortality risk fell in the BMI range of about 24 to 31, with the very lowest point sitting around 27 to 28.5The American Journal of Clinical Nutrition. BMI and all-cause mortality in older adults: a meta-analysis That same analysis found that older adults with a BMI at or below 20 had at least a 28% greater mortality risk compared with those in the 23 to 24 range. At 5’8″, a BMI of 27 translates to about 177 pounds, and a BMI of 28 is roughly 184 pounds. That is well above the textbook midpoint of 145 pounds.
Another review, pooling 97 studies covering nearly three million people, confirmed that the “overweight” BMI category of 25 to 30 was associated with the lowest mortality across all age groups, and that the harmful effects of higher BMI were blunted in later life.6PubMed Central. Excessive Body Weight in Older Adults: Concerns and Recommendations The practical takeaway: if you are over 65 and standing 5’8″, a weight in the range of roughly 155 to 195 pounds may be associated with better survival than the 125 to 145 range that younger-adult charts would favor. This does not mean that gaining fat is protective per se. Researchers believe the benefit comes partly from having enough metabolic reserve to survive illness, surgery, or periods of reduced food intake that become more common with age.
What “Frame Size” Actually Means for Your Weight
The concept of body frame goes back to the Metropolitan Life Insurance height-weight tables from the mid-twentieth century, which sorted people into small, medium, and large frames and gave different weight ranges for each. The idea was that someone with a bigger skeleton would naturally and healthily weigh more. The original tables used elbow breadth as the frame indicator, but research later showed that wrist and ankle breadths were actually better measures of skeletal frame because they relate to lean mass without being inflated by body fat. Elbow, shoulder, hip, and knee breadths, by contrast, were associated with both fat-free mass and total body fat, meaning they didn’t purely capture frame size.7PubMed Central. Do the new Metropolitan Life Insurance weight-height tables correctly assess body frame and body fat relationships?
Frame size is real, and it does affect how much you should weigh. Research confirms that broader skeletal dimensions are positively associated with both fat-free mass and bone mineral content.8The American Journal of Clinical Nutrition. Relations between frame size and body composition and bone mineral status A person with wide wrists, broad shoulders, and thick knee joints will carry more bone and muscle at the same height than someone with a narrow build. The traditional frame-based tables typically added about 10 to 15 pounds to the recommended range for a large frame compared with a small frame at the same height. At 5’8″, that means a small-framed person might aim for something like 130 to 145 pounds while a large-framed person might comfortably sit at 150 to 165 pounds, all within the broadly healthy BMI window.
The practical way to get a rough sense of your frame is to wrap your thumb and middle finger around your wrist. If they overlap easily, you likely have a small frame; if they just touch, medium; if there is a gap, large. It is a crude measure, but wrist circumference correlates reasonably well with skeletal breadth.
Sex Differences in Healthy Weight
Men and women at 5’8″ carry weight differently even when the scale reads the same number. Women have a higher percentage of body fat at any given BMI, while men carry more lean mass.9PubMed Central. Effects of fat distribution on lung function in young adults Women also tend to store fat in the hips and thighs, while men deposit it around the abdomen. That difference matters metabolically: the pear-shaped fat distribution typical of many women is associated with lower heart and metabolic disease risk compared with the central fat pattern more common in men.10PubMed Central. Sex differences in human adipose tissues – the biology of pear shape
Because of these compositional differences, a man and a woman who are both 5’8″ and 160 pounds are not in the same situation. The man may be carrying 20% body fat, which is well within healthy norms. The woman at 160 pounds might be at 28% body fat, which is also healthy for her age range. Reference values for body fat percentage in men aged 18 to 30 range from roughly 18 to 26%, while women in the same age group typically fall between 26 and 33%.11PubMed Central. Age- and sex-related differences in body composition in healthy subjects aged 18 to 82 years By age 60 and beyond, those ranges climb: roughly 22 to 31% for men and 32 to 40% for women. This steady increase with age partly explains why a slightly higher scale weight is normal and even protective in later decades.
When the Scale Misleads: Athletes and Muscular Builds
BMI is a population screening tool, and it fails visibly at the individual level when someone carries above-average muscle. A 5’8″ person who strength trains seriously might weigh 185 or even 200 pounds with a BMI of 28 to 30, technically overweight or borderline obese, while having a body fat percentage in the healthy teens. BMI can misclassify athletes with greater fat-free mass as obese, making it a poor tool for assessing their health or nutritional status.12PubMed Central. The Estimation of the Fat Free Mass Index in Athletes
Researchers have developed the fat-free mass index as a better metric for active populations. It adjusts lean mass for height, giving a number that reflects how much muscle someone carries relative to their frame. Among collegiate American football players, about a quarter had fat-free mass index values above 25, which represents an exceptional amount of lean tissue.13PubMed Central. Fat-Free Mass Index in NCAA Division I and II Collegiate American Football Players For non-athletes, values in the 18 to 20 range are more typical. The fat-free mass index provides context for whether someone’s weight is coming from muscle or fat, helping to qualify whether a “high” weight at a given height is a problem or a sign of fitness.14PubMed. Fat-Free Mass Index in Sport: Normative Profiles and Applications for Collegiate Athletes
If you are 5’8″ and 180 pounds because you’ve been lifting weights for years and have visible muscle definition with a moderate waist measurement, your situation is fundamentally different from someone at the same height and weight who is sedentary. The scale alone cannot distinguish between those two bodies.
Ethnicity and the Limits of One-Size-Fits-All Charts
Standard BMI cutoffs were developed primarily from data on White European populations, and they do not apply equally to everyone. A large population-based study in England found that the BMI at which South Asian adults reached the same risk of developing type 2 diabetes as White adults at a BMI of 30 was only about 24.15PubMed Central. Ethnicity-specific BMI cutoffs for obesity based on type 2 diabetes risk in England: a population-based cohort study For Black adults, the equivalent cutoff was about 28, for Chinese adults roughly 27, and for Arab adults about 27 as well.
A separate multicountry analysis echoed these disparities. In women, the BMI associated with the same diabetes risk as a BMI of 40 in White adults was about 27 in South Asian adults and about 32 in Black adults.16PubMed Central. Comparison of racial/ethnic-specific BMI cutoffs for categorizing obesity severity: a multicountry prospective cohort study The differences are substantial and have real clinical consequences. At 5’8″, a person of South Asian descent might face elevated metabolic risk at 160 pounds, while a person of West African descent might not reach the same risk level until closer to 185 pounds.
This means that any weight chart you find online, unless it specifies the population it was derived from, is probably calibrated for White adults. If your ancestry is South Asian, East Asian, or Middle Eastern, standard “healthy” ranges may overestimate how much you can safely weigh before metabolic risk climbs. Conversely, for Black adults, standard cutoffs may be somewhat conservative. These differences stem from variations in body composition, fat distribution patterns, and metabolic physiology across populations.
Why Waist Measurement Tells You More Than Weight
If you’ve read this far and feel that scale weight is a blunt instrument, you’re right. Researchers have increasingly focused on where fat sits rather than how much total weight you carry. Your waist-to-height ratio, calculated by dividing your waist circumference by your height, has emerged as a consistently better predictor of heart disease, diabetes, and early death than BMI.17PubMed. Waist-to-height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta-analysis A systematic review involving over 300,000 adults from multiple ethnic groups found that waist-to-height ratio was significantly better than both waist circumference alone and BMI at identifying risk for diabetes, high blood pressure, and cardiovascular disease in both men and women.
A meta-analysis confirmed that waist-to-height ratio had stronger associations than BMI with diabetes and metabolic syndrome, and was also superior for predicting cardiovascular disease mortality and all-cause mortality.18PubMed Central. Predicting cardiometabolic risk: waist-to-height ratio or BMI. A meta-analysis The rule of thumb is simple: keep your waist circumference below half your height. At 5’8″ (68 inches), that means your waist should ideally stay under 34 inches. This single measurement, requiring only a tape measure, captures abdominal fat distribution in a way that the bathroom scale never can.19PubMed Central. Waist-to-height ratio as a screening tool for obesity and cardiometabolic risk
Recent reviews of BMI’s usefulness agree that while it remains a valuable screening tool for large populations, it is inadequate for reliable individual risk prediction. People classified as overweight by BMI who are physically fit by other measures need fuller evaluation with combined body measurements and performance metrics rather than being told to lose weight based on a number alone.20MDPI. Advantages and Limitations of the Body Mass Index (BMI) to Assess Adult Obesity
The Joint Argument for Staying Within Range
Even setting aside metabolic disease, weight at 5’8″ matters for your skeleton. Research on knee osteoarthritis found that each pound of weight lost resulted in roughly a four-fold reduction in the load exerted on the knee during each step of daily walking.21PubMed. Weight loss reduces knee-joint loads in overweight and obese older adults with knee osteoarthritis That multiplier effect means that even modest weight changes have an outsized impact on joint health. If you are 5’8″ and carrying 20 extra pounds, your knees experience something like 80 additional pounds of compressive force with every step. Over thousands of steps per day and millions per decade, that load adds up.
This is particularly relevant for the “my weight is fine but my knees hurt” crowd. You don’t have to be dramatically overweight for the excess force to matter. Losing even 10 pounds at any starting weight translates to roughly 40 pounds less stress on each knee per step. For someone at 5’8″ who weighs 185 and is wondering whether getting down to 170 would make a real difference, the biomechanics say yes, emphatically.
Putting It Together by Age and Frame
No single number answers “how much should I weigh at 5’8″” because the honest answer depends on at least four variables: your age, sex, frame size, and ethnic background. But here’s a reasonable set of ranges based on the evidence, using round numbers:
- Ages 20 to 39, small frame: roughly 125 to 150 pounds for women, 135 to 155 pounds for men.
- Ages 20 to 39, medium frame: roughly 135 to 160 pounds for women, 145 to 165 pounds for men.
- Ages 20 to 39, large frame: roughly 145 to 170 pounds for women, 155 to 180 pounds for men.
- Ages 40 to 59: add roughly 5 to 10 pounds to each range above, reflecting normal age-related shifts in body composition.
- Ages 60 and older: a BMI of about 24 to 30 (roughly 158 to 197 pounds) is associated with the lowest mortality risk, regardless of frame. Being underweight in this age group carries a clearly higher risk than carrying some extra weight.
These ranges assume you are not a trained athlete carrying significant extra muscle. If you are, your healthy weight could easily exceed these numbers by 15 to 30 pounds. They also assume you are of European descent; if your background is South Asian or East Asian, the lower end of each range may be more appropriate, while Black adults may find the upper ranges more fitting for their metabolic profile.
The most useful thing you can do beyond checking your weight is to measure your waist. If you’re 5’8″ and your waist is under 34 inches, your risk profile is likely favorable regardless of whether the scale reads 150 or 175. If your waist exceeds that threshold, the fat you are carrying is disproportionately abdominal, and addressing that distribution matters more than chasing a specific number on the scale.