Dear Readers,
Hope you had a great time reading and understanding the Endocrine System (3.1/n). (Give it a read if you haven’t). You would have now realised the dominance of Endocrine system on almost every aspect of our bodily functions. To keep it simple, from now on, each article will be dedicated to dissect the role of Yoga on individual endocrine glands.
In this article we will examine the effects of Yoga on the Pineal Gland.
The TL;DR
Pineal Gland secretes melatonin, which regulates our internal clock. Our internal clock regulates the sleep-wake cycle
Yoga and Mindful Meditation have proven to improve sleep quality and overall wellbeing of participants enrolled in several clinical trials
Improvement in sleep quality was due to increase in melatonin secretion, decrease in inflammatory markers, increase in immune function, decrease in stress hormone and catecholamine levels.
Good sleep can help to reduce weight, boost immune function, cognitive function and prevent chronic diseases. In children, sleep helps in brain maturation.
Let’s dig deeper….
1. Pineal Gland or a vestigial eye (Yogi’s refer to this as the ‘Third Eye’)
Deep beneath the cerebral cortices, a vestigial eye measures and keeps time. Poor sleep hygiene, chronic stress, some drugs, age related calcification (deposition of calcium), diabetics with clinical autonomic neuropathy (nerves that control involuntary bodily functions are damaged) or enlargement by tumour often results in its dysfunction.
The most prominent symptom of pineal gland dysfunction is a change in your internal clock (circadian rhythm), that regulates the sleep–wake cycle. Simply it will mean either sleeping too much or too little, feeling active and restless in the middle of the night, or feeling sleepy at unusual times. This happens because pineal gland secretes melatonin hormone which regulates the natural sleep-wake cycle.
Darkness causes the pineal gland to produce more melatonin, which signals the body to prepare for sleep. On the other hand, light (especially the blue spectrum light coming from screens of smartphones, television, tablets), decreases melatonin production and signals the body to prepare for being awake. It’s important to note that brief pulses of light of sufficient intensity and duration also abruptly suppress its production.
Do you Know? Studies have shown that women exposed to light at night (eg night and shift workers) have a higher incidence of breast cancer.
In small amounts, melatonin is also produced in retina, lens, iris, ciliary body, lacrimal (tear) gland, skin, and gut. Melatonin is also present in fruit, vegetables, and wheat, however melatonin ingested with a normal diet does not significantly contribute to circulating levels.
You must have experienced the short-term effect of low melatonin levels after a jet lag or change in shift work. This short-term insomnia can be alleviated by oral dietary supplement of melatonin.
Other symptoms related to pineal gland dysfunction includes: osteoporosis, mental health issues, changes in menstrual cycle, difficulty with sense of direction, headache, tremors etc. Furthermore, Alzheimer’s patients also have low levels of melatonin which decreases their cognitive function, immune health and in turn disturbs their sleep cycle.
The schematic diagram of pineal gland dysfunction in Alzheimer Disease
Quite simply, our happiness and well-being is directly affected by harmony in the pineal.
Question: Would blind people without light-induced suppression of melatonin have sleep disorders ?
Several scientific studies have been conducted to understand the effects of yoga on sleep quality and insomnia on variety of different populations like, menopausal, peri- or post-menopausal women, breast cancer patients, old people, depressed and anxious people, opioid addicts, children with autism spectrum disorder, etc. These studies focused on quality of sleep rather than the quantity, as increased amounts of sleep do not necessarily correlate with quality sleep and overall wellbeing. Here, I’ll concisely discuss the overview of the study, results and limitations of some of these studies.
Let’s first understand about Sleep:
Sleep is a complex cyclic process. A cycle of sleep comprise of light sleep (stages 1 and 2) to deep sleep (stage 3) and then rapid eye movement (REM) sleep. It takes 70-110 minutes to complete one sleep cycle (Hypnogram, see Fig below).
Sleep cycle. N1 (Stage 1): drowsy or awake to falling asleep; N2 (Stage 2): Light Sleep phase; N3 and N4 (Stage 3): deep sleep; REM: dreaming phase
What are the indicators of Good Sleep Quality ?
Panel of experts at National Sleep Foundation (NSF) established the following key indicators of good sleep quality.
Sleeping time while in bed (at least 85% of the total time),
Falling asleep in 30 min or less,
Waking up no more than once per night and
If you wake up, it should take less than 20 minutes to fall asleep again.
Professionally, sleep quality can be measured by Pittsburgh Quality Sleep Index (PSQI), Insomnia Severity Index (ISI), or objective instruments such as polysomnography, actigraphy.
Actigraphy is a non-invasive technique used to assess cycles of activity and rest. It’s data is used to determine circadian rhythm disorders. An actigraph is worn like a watch on the wrist of your non-dominant hand.
Scientific Evidences:
In a systematic review, results from 19 different randomised controlled trials, including a total of 1832 women participants were statistically analysed. Meta-analysis demonstrated that yoga had a significant improvement in sleep quality when compared to control group. The analyses suggest that participants in the non-breast cancer subgroup and participants in the non-peri/postmenopausal subgroup were associated with greater benefits. One study reported improved sleep quality and decreased depression score in menopausal women (n=52) practicing yoga for 1hr each time, three times a week for 24 weeks when compared to control group (n=54).
Furthermore, yoga intervention potentially improved sleep stability in Menopausal women with hot flashes when compared with aerobic exercise.
In another study, it was observed that around 85% of healthy yoga practitioners reported reduced stress and over 55% reported improvement in sleep quality.
Meta-analysis of 6 randomised controlled trials with a total of 330 participants were evaluated to understand the effect of Mindfulness Meditation (MM) for Insomnia. Overall findings revealed that although there were no significant differences between MM and control groups in terms of total sleep time, significant effects were found in total wake time, sleep onset latency, sleep quality, sleep efficiency, and PSQI global score.
Elderly population often experience sleep related disturbances which range from snoring, night time awakenings to insomnia to restless leg syndrome. Studies have shown that regular practice of yoga (minimum 6-month yoga-based intervention) improves quality of sleep and also overall quality of life.
Cancer patients and long-term cancer survivors (2-5 years following the completion of their cancer treatment) regardless of disease stage or type of treatment received, suffer from insomnia and/or difficulty falling asleep and daytime fatigue. Several studies have examined appreciatively positive effects of Mindfulness Meditation, Yoga and Cognitive behavioural therapy for insomnia on Breast cancer patients. One such study suggests that a 6-week mindfulness-based program supports short-term improvements in stress, reduced fear of cancer recurrence, and pro-inflammatory signaling, decreased hot flashes/night sweating in premenopausal patients with breast cancer.
Another randomised controlled trial conduced on Breast Cancer subjects, used both subjective (ie, sleep diaries, the Pittsburgh Sleep Quality Index [PSQI]) and objective (ie, actigraphy) sleep measures to assess the effect of 6-week Mindfulness-based stress reduction (MBSR). Interestingly, findings suggested that patients who received MBSR (vs control group) demonstrated significant improvement in sleep efficiency, decreased number of awakenings and also actigraphy-associated sleep parameters at 12 weeks post-treatment.
Another study determined the effects of Hatha Yoga (practiced twice a week for12 weeks) on cancer patients. Remarkably, this study also observed improved sleep quality (using the PSQI) and decreased fatigue and markers of inflammation in patients practicing yoga as compared to control group. It’s interesting to notice here that a strong correlation was observed with the frequency of home practice between sessions with good quality sleep.
Remarkably, many scientific studies have also evidently demonstrated improvement in sleep quality, mood and cognitive functions in Alzheimer Disease patients and their caregivers after practicing yoga or meditation for 12-weeks
Physiologically, mindfulness based therapy modulates one or more of the following factors to improve sleep quality in different populations:
Increasing melatonin levels,
By reducing patients’ cortisol (stress hormone) and catecholamine levels (increases with sleep disturbance)
Reducing hyperarousal through metacognition shifting, and
Reducing inflammatory markers, like Nuclear Factor Kappa B (potent transcription factor responsible for activating inflammatory cytokines).
Increased activity of Interferon Response Factors (IRFs: transcription factor responsible for production of innate antiviral response genes); i.e., reversal of patterns previously linked to stress.
Improving immune function (as previously reported in patients with an improvement in depression).
Graph shows statistical significant (p < 0.002) improvement in sleep quality in patients after mindfulness awareness program (MAP) when compared to sleep hygiene education (SHE). Sleep quality was assessed based on PSQI score. Adapted from scientific article.
Limitation of these studies
These studies are promising but still need to be replicated in larger cohorts. Most of the studies relied on qualitative (sleep journals, questionnaires) data, it would be crucial to also measure the effects quantitatively using specialised equipment. Also, long-term follow up should be done to clearly understand the effects of Yoga and Meditation intervention on Pineal Gland.
Sleep Hygiene: 5 tips for better sleep
In addition, if you want to sleep like a baby then practice
Yoga restorative moves, Meditation and Breath Work to try for better sleep (list is not exhaustive):
Pashimotanasana (Sitting Forward Bend)
Viparita Karani (Legs up the Wall)
Supta Baddha Konasana (Reclined Butterfly)
Balasana (Wide knee Child’s Pose)
Savasana (Corpse Pose)
Yoga Nidra (Guided meditation)
Left Nostril Breathing (Surya Bhedana)
Ujjayi Breath (Ocean Breath or Victorious Breath)
Benefits of Healthy Sleep
Weight Loss: In one extensive study, children and adults with shorter sleep durations were 89% and 55% more likely to become obese, respectively.
Better concentration and productivity: A study of medical interns provided a good example. In that study, the medical interns, in addition to their original work schedule, were given extra work that extended their work time to more than 24 hours, and were about 36% more likely to make serious medical errors.
Improves Immunity
Prevents from chronic health problems, including heart disease, kidney disease, high blood pressure, diabetes, stroke and depression.
Increases energy
In the next article (3.3/n), I will cover the science behind the effects of Yoga on the Thyroid Gland.
If you found the article of interest and know someone who would love reading this, please do share!
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