Ayurveda is not merely medical science, but it is the science of life. The aim of Ayurveda is to prevent disease and to maintain health. Acharya Charaka has explained that the strength and lustre of human beings who knows the suitable diet and regimen for every season and practices accordingly are enhanced. But habituated things if to be given up then it is to be done slowly and gradually otherwise it may lead to Asatmyaja roga (allergic disease).
Acharya Vagbhata in his treatise Ashtang Hridaya Sutrasthana has stated the term ritu sandhi which means the last 7 days of the present season and first 7 days of the upcoming season. It is a period of 14 days. In ritu sandhi, one should gradually start rejecting the practices of the present season including the practices related to dietetic practise, lifestyle, and behaviour. At the same time, he or she should gradually start practising and adapting to the practices of the upcoming season including diet, lifestyle, and behavioural practices. The practices should be adapted in a step ladder pattern, so should let going process.
It is the period in which the body adapts itself to stressors of the incoming season. The regimen or diet prescribed for this period is calculated to help in a smooth change over. Therefore, in ritu sandhi, the regimen of the preceding season should be discontinued gradually and that of the succeeding season should be adopted gradually.
Ritu sandhi (transit season) lowers down the immune system of the body and makes the conditions favourable for the spread of the disease. One who fully knows the reasonable dependent activities done by him or her and the food taken by him or her and taking this into consideration prescribes his diet, and lifestyle then, he or she only increases his or her body strength and complexion and develop better resistance of sandhi kalgat disease (seasonal disorder).
Practising anything or letting go anything suddenly is not easy. Both are processes which need to be done gradually. The body does not tolerate when anything is implemented out of regular practice or withdrawn from regular practice suddenly. The body will take time to get adapted to any changes, be it letting go of the things or practising the new things.
Seasons and their ritu sandhis
Shishira (late winter) and vasanta (spring)
It ranges between 9th March and 22nd March. During sishira ritu, agni (digestive fire) is stronger, Kapha dosha accumulates in the body due to extreme cold environment and food which are heavy to digest are usually consumed. But as vasanta ritu commences Kapha liquifies due to heat of the sun and reduces agni (digestive fire) therefore, foods that are light and easy indigestion should begin. As per Ayurveda, during sishira ritu, foods dominant in sweetness, sourness and saltiness should be gradually reduced and use of spices and vegetable with pungent, bitter, and astringent tastes should be increased. Preventive therapies like Nasya (nasal medication), dry massage, and physical exercise should be gradually started in 14 days.
Vasant (spring) and greeshma (summer)
It ranges between 9th May and 22nd May. The heat of the sun increases in summer therefore, foods with pungent taste should be decreased slowly and diet which are sweet, cold, and liquid in nature should be consumed. The gradual change in the diet corresponding to the upcoming summer season helps in maintaining the health of your body. As spring and summer are included in the northern solstice (uttarayana kala), change to a considerable extent in diet, and lifestyle is not obligatory.
Greeshma (summer) and Varsha (monsoon)
It ranges between 9th July and 22nd July. Agni starts weakening and doshas start increasing during varsha ritu therefore, all measures to increase the digestive capacity should be adopted gradually. In Ayurvedic scriptures, sleeping during daytime is suggested in summer because of long days and shorter nights, but as Varsha ritu starts progressing, it should be avoided to prevent it from increasing doshas. One must start drinking boiled water during Varsha ritu.
Varsha (monsoon) and Sharad (autumn)
It ranges between 9th September and 22nd September. The person is accustomed to the cold due to monsoon which results in a sudden increase in pitta when a person is exposed to warm rays of the sun. Therefore, he or she should slowly start consuming a diet which includes amla, potato, green gram, and rice, and dominating in bitter, sweet, and pungent tastes.
Sharad (autumn) and Hemanta (winter)
It ranges between 9th November and 22nd November. As per Ayurveda, nights are longer during the winter season and one feels hungry early in the morning therefore, he or she should adopt to oil massage (abhyanga) which balances Vata. As the digestion power starts increasing, the diet should include soup with fatty substances, black gram, and freshly harvested corn.
Hemanta (winter) and sishira (late winter)
It ranges between 9th January and 22nd January. Sishsira ritu is stronger than Hemanta, therefore, all practices adopted in Hemanta should be adopted with more intensity. Practices of Hemanta ritu should be gradually stopped and diet, the lifestyle of shishira ritu should be started.
Although today seasons do not follow the perfect schedule the knowledge of ritu sandhi (interseason period) help in the prevention of many seasonal disorders. The secret to living a healthy life is adapting to seasons throughout the year.