Chrono-nutrition and healthy Aging
Human being’s longevity is only partially (15-30%) influenced by genetics. Every person’s personal life history and lifelong habits majorly influence their longevity. There are both positively correlated and negatively correlated genes in relation to longevity. Negatively correlated genes which are involved in inflammation and metabolism are chiefly regulated by circadian clock.
The circadian clock characteristics of a person changes during his lifetime from birth to death. This is because as a person ages, his/her interactions with the environment changes. During the process of evolution, most human beings are subjected to a day and night environmental circadian rhythm. Human beings’ internal biological clock keeps track of the environmental changes. The master clock otherwise known as central oscillator, in human beings rest in brain, specifically in the hypothalamus. There are also functional peripheral clocks in all parts of the body, which are otherwise called peripheral oscillators. Even though these clocks have autonomous behaviour, the outside atmospheric signal has the potential to realign its function in accordance with the external signals such as light, meal timing and exercise on an everyday basis. This process is called entrainment. These external signals are called Zeitgebers. Of all signals, light is the most potent signal, but various other factors such as exercise, food intake also affect the clock mechanism.
How does aging affect circadian rhythm?
Aging causes many physiological changes which increases the vulnerability to diseases. Recent research has shown that, the properties of the circadian clock changes over one’s lifetime, including changes to sleep, body temperature and melatonin secretions. As half of the elderly people suffer from sleep deprivation, which also includes longer time taken to fall asleep and less time in deep sleep, there is increased risk of poor cognitive performances due to poor sleep in.
Similarly, a person’s diet in synchrony with biological circadian rhythms is critical for maintaining healthy metabolism, if altered could lead to metabolic syndrome and other age-related disorders. In addition to it, aging results in decreased neurotransmitters, GABAergic synapse, resulting in disruption of SCN rhythms. Downstream of SCN, peripheral clocks also show attenuation as one ages.
Can timing of food intake affect health of elderly people?
Yes, proper timing of food intake in earlier part of life can impact health status of the people when they are in their latter part of life. chrono-nutrition which involves aligning nutritional intake with the body’s natural circadian rhythm is important because of its connection with age related diseases such as neurodegenerative diseases, hypertension, obesity, diabetes, heart diseases. Studies have shown that proper meal timing is quintessential for promoting muscle health in older adults.
Is there a connection between Gut health and chrono-nutrition?
There is a symbiotic relationship between the gut microbiome and chrono-nutrition. Gut microbiome is important for nutritional absorption and metabolism. Gut microbiomes exhibit circadian rhythm. The Microbial community in the gut changes throughout the day and the timing of food regulates the microbial fluctuations. A disruption to circadian rhythm is correlated with change in the microbial rhythmicity which subsequently results in deleterious effects on the human body.
Additionally, there is a gut-brain axis which is also influenced by the circadian rhythm through appetite hormones leptin and ghrelin which regulates the sensation of hunger and satiety by acting on hypothalamus. Moreover, serotonin production is also influenced nutrients intake and timing.
How can chrono nutrition affect brain function?
Research shows circadian rhythm is pivotal for proper brain function. Disruption of circadian rhythms due to aging can be linked with neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. Moreover, disruption of circadian clock can also serve as a biomarker for assessing the prognosis of such disorders.
what is the role of chrono-nutrition in the pathogenesis of neurodegenerative disorders?
Disruption of circadian rhythm plays a crucial role in the pathogenesis of neurodegenerative disorders by
- • disturbances in the production and release of neurotransmitters
- • oxidative stress
- • mitochondrial dysfunction
- • insulin resistance
- • disruption to antioxidants and omega-3- fatty acids which are neuroprotective.
Conclusion:
Aging is inevitable, and our personal lifestyle plays a major role in healthy aging. Since circadian disruption/ misalignment can manifest as numerous diseases in different stages of life, it is important for practising healthcare professionals to include chronotherapy which has shown promising outcomes in research studies. Further studies are needed to assess the effectiveness of such interventions and to develop novel treatments and better preventive care.
To know more about chrono-nutrition and how it affects female and male fertility, enrol in our Medline Academics Fellowship in Reproductive Medicine.