Nutrition, Food Safety, and Water, Sanitation, and Hygiene
Nutrition, Food Safety, and Water, Sanitation, and Hygiene
This domain tests nutrition assessment, foodborne risk, and safe water and sanitation. Expect questions on malnutrition classification, micronutrients, HACCP, pathogens, and WASH interventions.
Core rules and concepts
- Stunting is low height-for-age from chronic undernutrition; wasting is low weight-for-height from acute undernutrition; underweight is low weight-for-age. BMI is interpreted with age- and sex-specific charts in children and adolescents.
- Severe acute malnutrition includes severe wasting, bilateral pitting edema, or very low weight-for-height. It requires urgent assessment and therapeutic feeding; complications need facility care.
- Micronutrient deficiencies include iron-deficiency anemia, vitamin A deficiency, iodine deficiency disorders, and zinc deficiency. Food fortification, supplementation, and dietary diversity are complementary.
- HACCP identifies hazards and critical control points at each food-production step. Key food safety practices include temperature control, separation of raw and cooked food, safe water, and hand hygiene.
- WASH includes safe drinking water, sanitation, and hygiene. Handwashing with soap at critical times reduces diarrheal and respiratory disease.
Worked example
A 24-month-old has a weight-for-height z-score of -3.2 and no edema or medical complications. The reasoning is severe acute malnutrition by wasting. The child needs community-based management with ready-to-use therapeutic food, counseling, and follow-up, not just "eat more." If edema, poor appetite, or infection were present, referral for inpatient care would be needed.
Traps that cost marks
Do not use adult BMI cutoffs for children. Do not confuse stunting with wasting. Do not assume boiling water is enough if recontamination occurs. Do not treat food safety as only a restaurant issue; household practices matter.