The seasons have a natural effect on the three doshas. According to Charaka Samhita, the strength of a person is enhanced when suitable diets and routines are adopted according to each season. To attain this level of health, one must have knowledge of the qualities of the seasons and their influence on the three doshas. The doshas accumulate during seasons that share their elements or qualities. Once the dosha has accumulated beyond a certain limit, it becomes aggravated and symptoms of this may be manifested. Seasons opposite in nature to a dosha pacify it.
Spring
As the heat of the sun increases in spring, accumulated kapha starts to break up and disperse throughout the body. This weakens the digestive fire or jatharagni and causes many kapha related disorders. Coughs, sinus problems and hay fever are common during spring.
The heavy heating diet adopted in winter should be replaced with foods more suitable for warmer weather. Lighter foods that are cooler in nature should be substituted. Sleeping during the day should be avoided as it aggravates kapha. Regular physical exercise, gargling with warm water or herbal decoctions and drinking warm water are beneficial for preventing disease and alleviating symptoms of aggravated kapha.
Summer
During summer, the sun is at its strongest and heat increases pitta. Staying in a cool room or shady place during the day is recommended. Excessive exposure to the heat and sun may cause sunburn, heat or sunstroke. Aromas or essential oils that give a cooling effect like sandal or rose may be used. One should wear light colored clothes, and clothes should be loose and comfortable.
The diet should mainly consist of cooling, sweet foods and drinks. Cucumber, watermelon, fruits, fruit juices (not acidic or citrus varieties), grains, wheat, rice and milk are ideal. Lots of water, about six to eight glasses, should be consumed. Sour, pungent and salty foods should be avoided. Hot, spicy and acidic foods such as chilies, onions, garlic and spices should also be excluded from the diet or used in small quantities. Tea, coffee, alcohol and smoking should be avoided.
Autumn
In early autumn, pitta is aggravated, and as the conditions become cooler vata is increased. There is a lot of heat in the blood, causing skin irritations like rashes, inflammations, dryness and itching. Massage is good for the skin, and fluid intake should be maintained at six to eight glasses a day, to cleanse the internal system. Clothing that provides protection from the wind should be worn.
The digestive fire or jatharagni is not very strong, so heavy foods should be minimized in the early part of the season. Sweet, light foods are recommended. As it becomes colder and wetter, foods can become heavier and more heating in nature. Try to avoid sour, acidic foods, as they will increase pitta. Eat those vegetables and fruits that are in season, and rice, barley and wheat.
Winter
In winter there is natural accumulation of kapha due to the cold and wet environment, so efforts should be made to keep warm and dry. Vata may also become aggravated due to the cooler weather. Warm baths and sauna (svedana), sunbaths and living in an insulated or heated house are beneficial. Heavy, warm, dry cloths should be worn. In winter, body massage should consist of mainly dry rubbing. If there is aggravation of vata, warm oil may be used.
Avoiding cold or frozen foods and drinks, and light foods, is recommended. Warm drinks, and foods that have a heating effect are preferable. During winter the digestive power (jatharagni) is stronger. As the external atmosphere is so cold, the body retains heat inside and attempts to preserve it. Therefore, the internal digestive fire becomes stronger and is able to metabolize oils, fats and dairy products such as yogurt, milk and cheese. Heavier foods can form a larger part of the diet, because they are easier to digest with a strong digestive fire or jatharagni.