Adult BMI guide
What Is the Healthy BMI Range? 18.5 to 24.9 for Adults (NHS, 2026)
For most adults, a BMI between 18.5 and 24.9 is commonly described as the healthy BMI range. It is a useful reference for screening, but it is not a complete assessment of health and should be interpreted with personal context.
Quick answer
A healthy BMI range for adults is 18.5 to 24.9, the same band used by the NHS and the CDC. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or above is obesity. The range applies to adults aged 20 and older and is a screening guide, not a diagnosis.
What 18.5 to 24.9 means
BMI compares weight with height. A result from 18.5 to 24.9 falls inside the standard adult healthy weight category. At a population level, this range is often associated with lower weight-related risk than very low or very high BMI ranges.
For an individual, the range is a reference rather than a target. Two people with the same BMI can have different waist measurements, muscle mass, medical histories, and metabolic health markers.
Adult BMI categories
| Category | BMI range |
|---|---|
| Underweight | Below 18.5 |
| Healthy BMI range | 18.5 to 24.9 |
| Overweight | 25 to 29.9 |
| Obesity | 30 or higher |
Example healthy weight ranges by height
These examples show the approximate weight range that corresponds to BMI 18.5 to 24.9 for several heights. Values are rounded, so use the calculator for your exact height.
| Height | Approximate weight for BMI 18.5 to 24.9 |
|---|---|
| 5 ft 2 in | 101 to 136 lb |
| 5 ft 6 in | 115 to 154 lb |
| 5 ft 10 in | 129 to 173 lb |
| 6 ft 0 in | 137 to 183 lb |
| 160 cm | 47.4 to 63.7 kg |
| 170 cm | 53.5 to 72.0 kg |
| 180 cm | 59.9 to 80.7 kg |
| 190 cm | 66.8 to 89.9 kg |
Why the healthy range is not universal
BMI does not account for muscle mass, bone structure, body fat distribution, pregnancy, ethnicity, age, or individual medical conditions. A muscular adult may have a BMI above 24.9 with relatively low body fat, while an older adult may have a BMI in range but lower muscle mass.
Some people also have metabolic risk factors such as high blood pressure, abnormal cholesterol, or high blood sugar even when BMI is within the healthy range. That is why BMI should be one starting point, not the only measure.
Why the NHS and CDC use the same 18.5 to 24.9 range
The 18.5 to 24.9 healthy band comes from World Health Organization (WHO) classifications adopted internationally. That is why the NHS in the UK and the CDC in the US publish identical adult thresholds: below 18.5 is underweight, 18.5 to 24.9 is healthy weight, 25 to 29.9 is overweight, and 30 or above is obesity. When people search for the NHS BMI healthy range of 18.5 to 24.9, they are looking for confirmation of this exact band, and the answer is the same on both sides of the Atlantic for the general adult population.
The one place they differ is emphasis. The NHS highlights that people of South Asian, Chinese, and some other backgrounds may face raised health risks from a lower BMI of around 23, a point the CDC also acknowledges. For those groups a healthy target may sit lower than 24.9, which is why BMI should always be read with personal context.
What to do if you are outside the range
If your BMI is below 18.5 or above 24.9, the next step is not panic or self-diagnosis. Review your broader health picture: recent weight change, waist size, activity level, appetite, sleep, medications, blood pressure, cholesterol, blood sugar, and symptoms.
Professional guidance is especially important if weight changed unexpectedly, if you are pregnant, if you have a medical condition, or if you are considering a major change to diet or exercise.
Healthy BMI range FAQ
What is the NHS BMI healthy range of 18.5 to 24.9?
It is the adult healthy weight band. A BMI from 18.5 to 24.9 is classed as healthy by the NHS; below 18.5 is underweight and 25 or above is overweight.
Is the NHS BMI healthy range 18.5 to 24.9 the same for adults of all ages?
It applies to adults aged 20 and over. For people under 20, BMI is read against age- and sex-specific percentiles instead of the fixed 18.5 to 24.9 band.
Is a healthy BMI weight range 18.5 to 24.9 the same for men and women?
Yes. The adult healthy BMI range of 18.5 to 24.9 is the same for men and women; only the underlying body composition tends to differ.
What weight is a BMI of 18.5 to 24.9?
It depends on height. At 1.70 m it is roughly 53 to 72 kg (117 to 159 lb); at 1.60 m it is roughly 47 to 64 kg (104 to 141 lb).
Is BMI 24.9 still healthy?
Yes. A BMI of 24.9 is the top of the healthy range. Risk at 24.9 is essentially the same as at 25.1; the boundary is a reporting line, not a health cliff.
Why do the NHS and CDC use the same 18.5 to 24.9 range?
Both adopt the World Health Organization adult classification, so the general-population thresholds are identical in the UK and the US.
What BMI range is considered healthy for adults?
For most adults, 18.5 to 24.9 is commonly described as the healthy weight BMI range.
Is the healthy BMI range universal?
No. BMI does not account for body composition, pregnancy, ethnicity, age, or individual medical history.
Can someone be healthy outside the range?
Possibly. BMI is only one screening measure. A clinician may consider waist circumference, blood tests, activity level, symptoms, and history.
Can someone have health risks inside the range?
Yes. BMI does not show blood pressure, cholesterol, blood sugar, smoking, fitness, or diet quality.
What should I do if my BMI is below 18.5?
Avoid self-diagnosis. If low BMI is unexpected or accompanied by symptoms, speak with a qualified healthcare professional.
What should I do if my BMI is above 24.9?
Use the result as a starting point. Consider waist circumference, habits, and medical history, and seek professional advice if you are concerned.
References
Medical disclaimer
This page is for general informational purposes only and does not replace professional medical advice. Always consult a qualified healthcare provider for personal health concerns.