Brief Answer:
Oral intake has limited modulatory ability but CANNOT STOP production

Detailed Answer:
Thank you for your question. This question has actually been looked at in detail and you and your doctor may be happy to learn that the actual overall impact of dietary intake of melatonin whether in the form of foodstuffs or as straight up pills taken at bedtime for sleep purposes does not have nearly as great an impact on levels that are circulating in your bloodstream at nighttime compared to some impact during the day. Also, the impact of LIGHT on the production or not of melatonin is far more important and intense than the ingestion of dietary sources or supplements.

In conclusion, DARKNESS is the strongest environmental influence on the production of melatonin in the body is orders of magnitude greater than what is produced based upon dietary ingestion. Studies have demonstrated some minor influences on total melatonin production by ingestion of either supplements or dietary sources, however, in no study has it ever been shown nor would it be expected based upon the physiological principles of its production that dietary ingestion by itself can initiate a feedback loop effect on signaling in the hypothalamus by the diurnal synchronization neuronal network or pineal production of melatonin in order to halt its synthesis and release into plasma.

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This query has utilized a total of 20 minutes of professional time in research, review, and synthesis for the purpose of formulating a return statement.

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