BMI 18: What It Means

A BMI of 18 is classified as underweight according to the World Health Organisation (WHO) BMI scale.

• Underweight: BMI below 18.5
• Normal weight: BMI 18.5–24.9
• Overweight: BMI 25–29.9
• Obese: BMI 30 and above

Consider consulting a doctor about healthy weight gain strategies.

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