What is BMI?

BMI is a numerical value derived from your mass (weight) and height.3 It serves as an indirect proxy for body fatness.4 Because it only requires height and weight, it is a quick, inexpensive, and non-invasive way to categorize weight groups that may lead to health problems.5

How to Calculate BMI

Calculating BMI involves a straightforward mathematical formula.6 Depending on whether you use the Metric or Imperial system, the calculation varies slightly:

The Metric Formula:

BMI = weight (kg)/height (m)}^2

Standard BMI Classifications

According to the World Health Organization (WHO), adults (aged 20 and older) generally fall into the following categories:

BMI Range - Classification

18.5 - Underweight

18.5 – 24.9 - Normal (Healthy Weight)

25.0 – 29.99 - Overweight

30.0 and Above - Obese

Tips to Reduce BMI (Weight Loss)

If your BMI falls into the overweight or obese category, reducing it can significantly lower your risk of chronic conditions like heart disease and Type 2 diabetes.

Prioritize Protein and Fiber: These help you feel full longer. Focus on lean meats, beans, lentils, and plenty of vegetables.

Monitor Portion Sizes: Even healthy foods can lead to weight gain if eaten in excess.

Increase Physical Activity: Aim for at least 150 minutes of moderate aerobic activity (like brisk walking) or 75 minutes of vigorous activity per week.15

Limit Liquid Calories: Sodas, sugary coffees, and alcohol often contribute calories without providing satiety.16

Tips to Increase BMI (Healthy Weight Gain)

If you are in the underweight category, the goal is to gain weight through muscle mass and healthy fat rather than processed junk food.

Eat More Frequently: Instead of three large meals, try eating five to six smaller meals throughout the day.

Choose Nutrient-Dense Foods: Opt for whole grains, nuts, seeds, avocados, and full-fat dairy.

Strength Training: Focus on weightlifting. This ensures that the extra calories you consume are converted into muscle rather than just body fat.

Smoothies and Shakes: Liquid nutrition can be easier to consume when you aren't feeling hungry. Mix in protein powder, nut butters, or oats.