Canadian Guidelines for Body Weight Classification in Adults - Quick Reference Tool for Professionals (10 mins)

Read the entire guide.  This resource gives you access to a table (in metric units) to assess BMI risk levels, as well as BMI combined with waist circumference risk level. Of note, this resource explicitly states that a BMI below 18.5 is associated with a higher risk of undernutrition, malnutrition, osteoporosis, infertility and an impaired immune system.