Ayurveda describes everything in nature as made of five elements (pancha mahabhuta) — space, air, fire, water and earth. In the living body these combine into three functional forces called doshas: Vata, Pitta and Kapha. They are not substances you can find under a microscope but a way of describing how the body moves, transforms and holds together.
Vata — movement
Vata, made of air and space, governs all movement: breath, circulation, nerve impulses, elimination and the movement of thought. Its qualities are dry, light, cold, rough, subtle and mobile. In balance it brings creativity and quickness; out of balance it shows as anxiety, insomnia, dry skin, constipation and aches. Its main seat is the colon.
Pitta — transformation
Pitta, fire with a little water, governs digestion, metabolism, body temperature, vision and understanding. Its qualities are hot, sharp, light, oily and spreading. In balance it gives clear intelligence, courage and good digestion; in excess it appears as acidity, inflammation, rashes, irritability and perfectionism. Its main seat is the small intestine.
Kapha — structure
Kapha, earth and water, provides structure, lubrication and stability — joints, mucous membranes, immunity and endurance. Its qualities are heavy, slow, cool, oily, smooth and stable. In balance it brings calm, loyalty and strength; in excess, heaviness, congestion, weight gain and lethargy. Its main seat is the chest.
Prakriti and vikriti
Everyone has all three doshas. The proportion fixed at conception is your prakriti, or constitution; your current state of imbalance is vikriti. Ayurvedic care aims to bring vikriti back towards prakriti — using the principle that like increases like and opposites balance. A Vata imbalance, for example, calls for warm, moist, grounding food and routine.
Online dosha quizzes can be a fun starting point, but a proper assessment by a practitioner includes pulse examination, observation and a detailed history.