Some interesting studies are cited that indicate meditation, yoga, fruit, and darkness all increase our melatonin (a pineal gland metabolite; often referred to as a miracle hormone). We know that artificial lighting and bad diet have left us chronically deficient in this hormone – a fact with vast implications for neurodegenerative diseases -but just how far back does the deficiency go if, at one time, we were eating a high percentage of fruit biochemistry for millions of years in the African tropics?
Darkness is good for us; it is an ally that heals us. It is something to be embraced, not feared. From Palaeolithic times, up until very recently, the only major sources of light we would have experienced once the sun went down would have been starlight, moonlight and firelight. Life on this planet has evolved for three and a half billion years with a regular and dependable day-night schedule. Now many of us are subject to electrical lighting long into the night, or over the entire duration, the most likely suspect being street lighting. This is far out of balance from how the sleep/wake cycle of our brain’s evolved. This artificial light pollution has a highly detrimental effect on our circadian rhythms, by repressing our nightly melatonin production, the release of which is triggered by darkness. Many people may not consider light to be a pollutant, or to even have the potential to be damaging as it is much less tangible than other environmental pollutants. But excess light, in the wrong place, at the wrong time should be considered a major pollutant that threatens health and well-being. This is especially important given that is well known that melatonin production declines with age as it is, and it is implicated with an ever increasing number of health impacts beyond simply making us feel sleepy when darkness falls.
The health ramifications of disturbed sleep and the direct effects of melatonin suppression should be considered separately, while at the same time being intimately linked. Melatonin is an endogenous neurohormone made in the pineal gland in the brain. It is a very potent antioxidant and free radical scavenger, protecting cells, and has neuroprotective properties. It also affects DNA repair, interacting with DNA helicase enzymes and via its actions on several key genes involved in DNA responsive pathways. It acts as a buffer against DNA damage, cellular mutation and cancer, and lowered levels of the hormone have been linked to several kinds of cancer in a number of different studies. Melatonin suppression has also been linked to impaired immune system function and to a number of different diseases. It plays a role in glucose metabolism, and its suppression has been linked with type-2 diabetes. The negative effects of disturbed sleep and sleep deprivation are serious; having been linked to depression, car and workplace accidents, learning and memory deficits and an increased risk of cardiovascular disease and diabetes, and an overall increase in mortality.