Every season has two aspects in terms of Dosha, which can be understood as the vacillation of a ball from its rope. The ball goes from one end to the other. Two things happen at the same time. The ball goes to one end and, in the process, generates the momentum to go to the opposite end. Similarly here we can consider 3 Dosha to be at play. One Dosha is active during one season with its effects and another Dosha is getting filled up, at the same to time, to be released in the next season, the third Dosha being balanced. This also can be considered as an effect of inertia of the body while adjusting to the changes in the outer environment.
Also, not all Dosha get imbalanced at the same time. This is so because the qualities of one Dosha conflicts with the other and therefore they balance each other. For example Vata is exaggerated by cold, whereas Pitta is diminished by the same factor.
Health in any season is dependent on 2 factors – Food and Lifestyle. Food affects the body internally and lifestyle affects from outside. If appropriate food and lifestyle is followed, the person will never suffer from any disease and will constantly go adding healthy years to his lifeline.
Internal homeostasis of people living in cold climates fluctuates very little from the ideal healthy state (provided they have enough heat and food) and therefore they have more chances of living healthy and longer.
Ayurvedic Ritucharya (seasonal cycle) according to Charak Samhita starts with the ideal state, the healthiest season Hemant (fall).
Winter is the healthiest season. According to Charak, because of the cold temperatures, the blood vessels nearer to the skin, contract. The heat of the body thus preserved, fires up the hunger and helps in digestion. Two ways benefit is that the body can intake more food and nutrients and on the other hand, as digestion power is strong, no toxins (Aam ras) due to improper digestion are formed.
But there is a flip side too. If you do not take proper nutrition during winters then this fire of hunger (Pachakagni) will start burning the body fat (Kaphaj parts) and vitiate the Vata (space and motion element).Therefore it is very important to take healthy and ample amount of food. If the body fat decreases, insulation benefits of the fatty layer go as well and it becomes difficult to preserve the heat. In turns, one will feel more hungry, in order to generate some heat through food. This negative spiral might result in even death. This is the reason why the healthiest season also has a lot of poor dying because of low availability of food, proper clothing and shelter.
People living in cold climate are mostly non-vegetarian, which suits them well for multiple reasons. Vegetables or plant food might not be easily available in very cold areas and meat provides adequate nutrition and heat (during digestion) to the body in the cold. Body is also able to digest and absorb the food properly, because of good digestive power. Meat can be conveniently preserved in cold climate and is safer to use for longer duration, as compared to the hotter climates.
People in the hotter areas have a huge assortment of vegetables, fruits, herbs and spices to live on. Vegetarian diet is easier to digest, produces lesser heat and creates lesser toxins while getting digested. It has lots of roughage to prevent constipation, since the body in hot temperatures also lose water through perspiration and might not be adequate to drain the food conveniently through intestines.
Nature has devised its own mechanism to keep the inhabitants of all places completely healthy and to have a long life, if they stick to the circle of health!
Let us take the example of brief description of Swasthvritta in the seasons
Aahar in winter – This is the time when you should eat heavy food. (It is very important to note that everything is relative. If you are living on salad, you can start by little oily food. But you should not jump to deep fried food at once.) Also the food should be taken according to one’s Prakruti.
Aahar in summer – This is the time to have light and easily digestible food, also have natural heat busters like water melon etc…
Note – In summer basically all things, living and non-living lose water because of heat and become dry. The effect of heat and dryness on the body depends on the kind of place you live in. If you live on a mountain, the summer will be more like the spring of the plains. Therefore you have to decide the duration for which you want to follow the summer treatment.
Changes in Ritu
State of mind – Seasons affect brains of lower level animals through hormonal changes, as they do not have higher level of intelligence and mental control. Humans by and large, can control their minds. Still there is a little effect of seasons on the mind which will be discussed in detail with SAD (Seasonal Affective Disorders)
State of body – Dosha and Bal (body strength) changes according to seasons