Words: Dr Punyakishore MAIBAM
All life forms on earth have evolved to coping with the rotating nature of our planet. The result: the alteration between day and night. The specifics of this cycle differ in micro-organisms, fungi, bacteria, plants and animals; however, the consistent feature is a ‘biological clock’ — it allows the organism to anticipate and prepare for the change. The biological clock keeps track of night and day; it synchronises with the light received from the retina. This is further interpreted in the brain.
It is also important to note that all animal cells have their own clocks; however, the clocks do not differ much as it is hugely linked to day and night. These biological clocks have a cycle which is close to the 24-hour pattern of light and darkness. This is also called the circadian cycle. This concept, which is now a topic of intense research throughout the globe, has been well explained in Ayurveda, a long, long time ago.
There exists, according to Ayurveda, an internal clock, in our body, which is in sync with our day and night cycles. This regulates our levels of energy and elucidates that certain functions are most beneficial, or optimal, at a particular time of the day. Hence, the terms, Ayurveda clock, biological clock, and circadian clock, share almost similar perspectives.
Ayurveda also advocates the concept of immunity as not only protection from disease, but also the promotion of physical as well as mental health with the term, vyadhikshamatva — which is closely intertwined with the Ayurveda clock.
The Ayurveda, or circadian, clock co-ordinates an organism’s daily rhythms in molecular, physiological, and behavioural processes. It also plays a specific role in synchronising functions of the immune system when the organism is in a healthy state and specifically when there are threats of infection.
The disruption of our circadian cycle results in a number of health issues, including obesity and diabetes, defective immune response and cancer.
Circadian Clock & Immune System
This article focuses on the role of the internal circadian clock system on our immune system. The immune system, a complex network of cells comprising special organs, cells and chemicals, guards our body against infection [microbes]. The white blood cells [WBC], which include B and T-lymphocytes, antibodies, the lymphatic system, spleen, thymus, bone marrow and the complementary systems, constitute the foremost parts of the immune system, which actively fight infections. Several immune responses, such as leucocyte mobilisation, trafficking, chemotaxis to cytokine release, and T-cell differentiation are mediated in a daily manner, or are dependent on the time of day. Cytokines are signalling molecules which play a key role in immune function; their timing and amount of production are regulated by the circadian clock.
One of the keys to good health, according to Ayurveda, is living in tune with nature’s cycles. Ayurveda has emphasised, ages ago, the importance of a connection with nature for millennia; many people around the globe are only now beginning to understand exactly how important it is for the body to stay connected to the rhythms of nature.
Everything in nature works in a rhythm and we, human beings, are also part of this nature resulting in optimal functioning when the rhythm is maintained. Our 24-hour Ayurveda biological cycle influences our sleeping and waking cycles, the release of hormones, eating patterns, digestion, temperature of our body and other important bodily functions. The earth’s rotation around the sun creates a 24-hour cycle of light and dark — this impacts human health in many ways. It is imperative that the Ayurveda, or circadian, cycle affects the gene expression metabolism and functions that have a colossal role to play in our well-being, including liver and cardiovascular functions and blood glucose regulation.
The Ayurveda clock may be categorised into six cycles, out of which three cycles occur during the day, while three cycles occur during the night. It is well-known that Ayurveda is built on the five great elements, viz., earth, water, fire, air and space. Ayurveda relates to the famed three doshas, viz., vata, pitta and kapha, formed by combining the five elements cited.
Dosha is a Sanskrit word for disease, fault, or defect. According to Ayurveda, the three doshas describe the fundamental qualities of the elements; the three doshas are considered to govern our mental and physical responses. Ayurveda suggests that vata is the lightest dosha [air and space], pitta the hottest dosha [fire and little water] and kapha, the densest dosha [earth and water].
Day Cycle [Kapha, Pitta & Vata]
6:00am-10:00am [Kapha Time]. Time periods always begin with kapha dosha. According to Ayurveda, getting up [ideally before 6:00am] and engaging in certain early morning exercises, or activity, to get our heart pumping with an energetic start is considered the best practice. Also, having a light well-spiced breakfast is advised.
10:00am-2:00pm [Pitta Time]. Kapha time flows into pitta time. It is the time when the sun is at its peak in the sky — this is the time of productivity, because there is sufficient heat in the natural world. During this time, heat naturally predominates our body and mind; this makes it ideal for physical activities. This is the best time to have the largest meal of the day — lunch.
2:00pm-6:00pm [Vata Time]. As the day progresses, the pitta period time fades and the vata time begins. Thus, vata represents the time of transition; it is characterised by calm and peaceful environment. It allows the best of creative and expansive thinking, making it the ideal time for problem-solving and creative pursuits.
Night Cycle [Kapha, Pitta, and Vata Repeat]
6:00pm-10:00pm [Kapha Time]. As we move towards night, the cycle continues and times ruled by the doshas again repeats. Kapha becomes once again dominant; its heavy qualities indicate that it’s time to wind up, have a light dinner, and settle in for the night.
10:00pm-2:00am [Pitta Time]. When the kapha time starts, it is considered best to snug in bed and have a sound sleep. It is vital to sleep during this time as the activities inside the body predominantly related to internal cleansing take place.
2:00am-6:00am [Vata Time]. The vata time of the night cycle marks another time of transition. This time, which represents the early morning, is not an ideal time of creativity; instead, you’d consider it best for receptivity. It is, therefore, the best time for prayer, meditation, and other spiritual practices.
When human beings sleep, it heralds the time for resetting our bio-clock with nature’s clock. Today’s highly competitive society has compelled us to listen to the demands of our work, while ignoring the needs of the body and nature’s rhythms. The alteration in sleep and eating patterns usually disturb the primary circadian system which, thereafter, influences the gut microbiome; this results in metabolic health issues. Thus, frequent disruption in the pattern of eating and sleeping immensely impacts our mind-body system. This can lead to a weakening immune system and different kinds of diseases. People with certain disorders and weakened immune systems are more likely to get severely affected by any disease, including COVID-19, as compared to individuals who strictly follow the Ayurveda clock. Maintaining the circadian clock helps in a better immune response. It would, therefore, be beneficial to switch our routine in accordance to our Ayurveda cycle and make small changes to adjust our habits over time — more so to combating a tempestuous pandemic like COVID-19.
Conclusion
The circadian cycle is closely intertwined with our immune system, as it regulates cytokine production and the activity of immune cells, such as T-cells and B-cells, while lowering our susceptibility to infections and immune-related disorders. The bottom line is simple, also profound — maintaining a healthy circadian cycle is important for optimal immune function. This can be achieved through good sleep hygiene, balanced diet, regular exercise, and exposure to natural light during the day.
