The Melanin Factor - Part II - Daytime Circadian Rhythm, Melatonin, Dopamine, Melanin, and Food Precursors

So take a deep breath, the diagram below may look complicated, but I'll try to make it simple. A more detailed explanation is in the book.

On the left, you see a chain of chemical reactions that happen in your body to convert tyrosine from your food (eggs, fish, shrimp, nuts, lima beans, many others) into L-DOPA, then into dopamine, then into norepinephrine, and finally into epinephrine (aka adrenaline).  The cascade from tyrosine to dopamine physically takes place within your dopaminergic neurons (such as in the substantia nigra, or in the gut, or kidneys).  The last part, from dopamine to adrenaline takes place in your adrenal medulla (locus coeruleus) in your brain stem, and elsewhere in your body.

If we want to activate melanin production, we have to activate the pineal gland to produce melatonin, and the melatonin in turn activates the pituitary gland to produce melanin stimulating hormone (MSH).  The MSH then goes everywhere in the body that has cells, called melanocytes, to produce melanin.  Then cells turn on and start producing melanin, using up L-DOPA as a substrate to produce the melanin. Even critical neuromelanin in the brain is produced, which is greatly needed for PD sufferers (see The Melanin Factor - Part I). 

Things like excess dopamine, nicotine, and nutrients find affinity for the melanin and act as a reserve.  So the pigment is far more important than its color.

Starting at first daylight, light on your face, blue light in particular, activates the retina, sending a signal to your Super Chiasmic Nucleus (SCN) in your brain, which in turn activates receptors on your pineal gland to respond to dopamine, shutting off the production of melatonin.  This is good for the daytime because excess melatonin shuts off dopamine production, so now, in the daytime, our body is setup to flourish, ideally producing lots of excess L-DOPA and dopamine from our food.  Excess melatonin then fulfills antioxidant duties, thwarting poisons, UV light, and so on.  Excess MSH continues to activate pigmentation. 

Meanwhile nicotine, acetylcholine, and muscarine are busy triggering the use of dopamine in neurotransmission.  If all is well - with excercise, sunlight, powerful food, and without stress - very little dopamine is consumed to make adrenaline and we get a very nice excess supply of L-DOPA and dopamine.

And so we have the first dip of the seesaw between daytime dopamine and nighttime melatonin, a major swing in the circadian rhythm cycle.

All of this is setting the stage for melanin-production success at nighttime, which I will describe in The Melanin Factor - Part III.

Stay Tuned,

Glen Pettibone