The prakrati or constitution of a person is based on three important characteristics called doshas which are: vata, pitta and kapha. Each dosha is made up of one or two of the five basic elements: space, air, fire, water, and earth. Each dosha has a particular function and can alter the body for different reasons. Doshas are constantly being formed and balanced through diet, activity, and bodily processes. An imbalanced dosha will produce symptoms that are related to that dosha and are different from the symptoms of an imbalance of another dosha.

Imbalances can be due to an unhealthy lifestyle or diet; too much or too little physical and mental effort; or not being adequately protected from the weather, chemicals, or germs.

Vata dosha is a combination of the elements space and air. It is the most powerful dosha because it controls very basic bodily processes such as cell division, the heart, respiration, and the mind. It becomes unbalanced, for example, by staying up late at night, eating nuts, or eating before the previous meal is digested. People with vata as their main dosha are believed to be especially susceptible to skin, neurological, and mental illnesses.

Pitta dosha is a combination of fire and water. Pitta is said to control hormones and the digestive system. When pitta becomes unbalanced, a person can experience negative emotions (such as hostility and jealousy) and have physical symptoms such as heartburn. Eating spicy or sour foods; being angry, tired, or fearful; or spending too much time in the sun can upset Pitta. People with a predominantly Pitta constitution are believed to be susceptible to heart disease and arthritis.

The kapha dosha is a combination of water and earth. Kapha helps maintain strength and immunity and control growth. Kapha dosha imbalance can cause nausea immediately after eating. Sleeping during the day, eating too many sweet foods, eating after one is full, and eating and drinking foods and drinks with too much salt and water can disturb the Kapha Dosha. People with a predominant kapha dosha are believed to be vulnerable to diabetes, gallbladder problems, stomach ulcers, and respiratory diseases such as asthma.