Melatonin influences the immune system and evidence is accumulating that it is a regulator of sex hormone production and useful in several male and female conditions. Melatonin deficiencies have been seen in patients with in cancer, heart disease, ulcers, Alzheimer’s, and SIDS, although some of these correlations don’t appear to be particularly strong. It seems as though melatonin encourages some level of restorative function during sleep. There is moderately good evidence from controlled experiments that melatonin will increase life expectancy in some cancer patients.
Signs, symptoms & indicators of Low Melatonin Level
Not being helped by melatonin
Night eating
Constant fatigue
Forgetting dreams
Conditions that suggest Low Melatonin Level
Night Eating Syndrome
Melatonin levels were found to be generally lower in patients with Night Eating Syndrome.
Low Progesterone or Estrogen Dominance
One of melatonin’s roles is the reduction of estrogen production in the body, and probably also reduction of the number of estrogen receptors. Studies have shown that the protective, estrogen-reducing effects of melatonin are significantly reduced by excessive exposure to light (including late night TV viewing) and probably electromagnetic fields, chemical pollutants such as pesticides and fungicides, and many commonly prescribed drugs, such as beta blockers for heart disease, high blood pressure and headaches.
Endometrial Cancer
A 1998 report found an extraordinarily strong correlation between melatonin level and endometrial cancer. Women were selected who appeared that they might have endometrial cancer. The women who in fact did not have endometrial cancer had an average melatonin level of 33. The women who had endometrial cancer had an average melatonin level of 6. There was little overlap between groups – by using melatonin levels alone, 94% of the patients could have been correctly categorized. A 1992 report proposed that decreased melatonin levels could contribute to endometrial cancer.
Premenstrual Syndrome / PMDD
Melatonin can exhibit strong effects on the reproductive system, and the activity of the female hormones estrogen and progesterone is closely tied with its regulation of the sleep-wake cycle. Abnormal biological rhythms and sleep-wake cycle disturbances are often a primary feature of periodic depression, another common characteristic of PMS. Melatonin imbalances have been specifically linked to PMS.
A study reported finding that women with PMS had an earlier decline in melatonin secretion, resulting in a shorter overall secretion time. “The data demonstrate that women with premenstrual syndrome have chronobiological abnormalities of melatonin secretion… The fact that these patients respond to treatments that affect circadian physiology, such as sleep deprivation and phototherapy, suggests that circadian abnormalities may contribute to the pathogenesis of premenstrual syndrome.” [Arch Gen Psychiatr 1990;47(12): pp.1139-46]
Risk factors for Low Melatonin Level
Having very/having low melatonin levels
Counter Indicators
Having normal/having elevated melatonin levels
Melatonin use
Low Melatonin Level can lead to
Cancer / Risk - General Measures
People with higher levels of melatonin might be less likely to develop cancer, and people with lower levels seem to be more likely to develop at least some forms of cancer. At pharmacological levels (5-50mg), melatonin seems to be useful in fighting active cancers. Neither of these effects are huge – a lack of melatonin does not always cause cancer, and a large dose of melatonin does not always cure cancer. However, both effects seem large enough to be important.
Increased Risk of Breast Cancer
Based on questionnaires from 78,562 women participating in the Nurses’ Health Study, reports that women who worked 30 or more years on the night shift, with at least three night shifts per month, had an almost 40% greater risk of developing breast cancer compared with those who worked the usual day shift.
A second study reports that nighttime bright light exposure is linked to increased breast cancer risk. It is possible that exposure to more light at night – a common phenomenon in industrialized nations – may account for increased cancer risk in women, independent of night-shift work. Another study found only a suggestion of greater risk with the brightest bedrooms, and no additional risk when turning on a light temporarily during the night. [J Natl Cancer Ins 2001;93: pp.1557-1562]
One theory is that decreased levels of the brain hormone melatonin are responsible, since this chemical is known to regulate daily sleep-wake cycles. Previous research suggests that unusually low levels of melatonin, which can be seen if humans are exposed to light during the night, may promote tumor growth. Normally, melatonin levels are highest during nighttime darkness and lowest during the daytime light.
The clinical experience of Dr. Pat Elliott, ND has been that a large proportion of young women with a close family history of breast cancer have low melatonin levels themselves. One researcher noted that for breast cancer, the decline of melatonin corresponds to growth of the cancer. This relationship is correlational, but it does suggest that there might be a causal relationship and that melatonin might fight this cancer.
To view more detail regarding breast cancer, melatonin and restrictive clothing, please go to the Breast Disease Time Line article.
Increased Risk of Endometrial Cancer
Decreased melatonin levels probably contribute to an increased risk of endometrial cancer. See link between Low Melatonin Levels and Endometrial Cancer.
Endometrial Cancer
A 1998 report found an extraordinarily strong correlation between melatonin level and endometrial cancer. Women were selected who appeared that they might have endometrial cancer. The women who in fact did not have endometrial cancer had an average melatonin level of 33. The women who had endometrial cancer had an average melatonin level of 6. There was little overlap between groups – by using melatonin levels alone, 94% of the patients could have been correctly categorized. A 1992 report proposed that decreased melatonin levels could contribute to endometrial cancer.
Recommendations for Low Melatonin Level
Change In Clothing Habits
The results of a study by Japanese researchers suggest that skin pressure by clothing (girdle and bra) could markedly suppress the nocturnal elevation of salivary melatonin, which resulted in an increase of core temperature. [Chronobiol Int 2000 Nov;17(6): pp.783-93 ] This confirms another study indicating that wearing a bra for extended periods increases the risk of breast cancer – and suggests that the connection may be through a depression in melatonin.
To view more detail regarding breast cancer, melatonin and restrictive clothing, please go to the Breast Disease Time Line article.
Fluoride Reduction/Avoidance
Work from Dr. Jennifer Luke (50-51) indicates that fluoride reaches one very important gland in the body, the pineal gland, at very much higher concentrations than 1 ppm. This small gland is almost at the geometrical center of the brain, between the two hemispheres. However, it is outside the blood brain barrier. It also has a very high supply of blood (a perfusion rate second only to the kidney) and it is a calcifying tissue, laying down crystals of calcium hydroxyapatite like the teeth and the bone. Because of these observations Luke argued that one would expect the pineal gland to concentrate fluoride. When she had the pineal gland from 11 human corpses analyzed she indeed found this to be the case. The levels of fluoride in the apatite crystals averaged about 9,000 ppm (and went as high as 21,000 ppm). The average level is as high as you would expect in the bones of someone afflicted with skeletal fluorosis. The average projected by Luke for the whole tissue was 300 ppm, well over the 1 ppm found to inhibit many enzymes.
Luke next examined the effect of dosing Mongolian gerbils (the animal of choice for studying the pineal gland) with fluoride. She found that animals fed higher doses of fluoride had a significant decrease in their excretion of melatonin metabolite in their urine. She also found that the high dose fluoride animals took a shorter time to reach puberty. This is exactly what you would expect if melatonin production was lowered. If this result is confirmed by others it would make fluoride an environmental hormone or endocrine disrupter, a topic of intense discussion (52) and review by regulatory agencies in the US and around the world.
50. Luke, J. (1994). Effects of Fluoride on the Physiology of the Pineal Gland. Caries Research, 28, 204.
51. GGVideo [Grassroots and Global Video] (1999). Fluoride, the Pineal Gland and Melatonin: An Interview with and Presentation by Dr. Jennifer Luke. Videotape, length 40 minutes. Available from GGVideo, 82 Judson Street, Canton, NY 13617. Tel: 315-379-9544. Fax: 315-379-0448. E-mail: ggvideo@northnet.org
52. Colborn, T. et al (1996). Our Stolen Future: Are We Threatening Our Fertility, Intelligence, and Survival? Dutton, NY, NY.
Key
| Weak or unproven link |
| Strong or generally accepted link |
| Proven definite or direct link |
| Strongly counter-indicative |
| Very strongly or absolutely counter-indicative |
| Likely to help |
| Highly recommended |
Glossary
Melatonin
The only hormone secreted into the bloodstream by the pineal gland. The hormone appears to inhibit numerous endocrine functions, including the gonadotropic hormones. Research exists on the efficacy of melatonin in treating jet lag and certain sleep disorders. Dosages greater than l milligram have been associated with drowsiness, headaches, disturbances in sleep/wake cycles and is contraindicated in those who are on antidepressive medication. It also negatively influences insulin utilization.
Hormones
Chemical substances secreted by a variety of body organs that are carried by the bloodstream and usually influence cells some distance from the source of production. Hormones signal certain enzymes to perform their functions and, in this way, regulate such body functions as blood sugar levels, insulin levels, the menstrual cycle, and growth. These can be prescription, over-the-counter, synthetic or natural agents. Examples include adrenal hormones such as corticosteroids and aldosterone; glucagon, growth hormone, insulin, testosterone, estrogens, progestins, progesterone, DHEA, melatonin, and thyroid hormones such as thyroxine and calcitonin.
Estrogen
One of the female sex hormones produced by the ovaries.
Testosterone
The principal male sex hormone that induces and maintains the changes that take place in males at puberty. In men, the testicles continue to produce testosterone throughout life, though there is some decline with age. A naturally occurring androgenic hormone.
Tryptophan
Essential amino acid. Natural relaxant and sleep aid due to its precursor role in serotonin (a neurotransmitter) synthesis. Along with tyrosine, it is used in the treatment of addictions.
Anti-inflammatory
Reducing inflammation by acting on body mechanisms, without directly acting on the cause of inflammation, e.g., glucocorticoids, aspirin.
Immune System
A complex that protects the body from disease organisms and other foreign bodies. The system includes the humoral immune response and the cell-mediated response. The immune system also protects the body from invasion by making local barriers and inflammation.
Cancer
Refers to the various types of malignant neoplasms that contain cells growing out of control and invading adjacent tissues, which may metastasize to distant tissues.
Ulcer
Lesion on the skin or mucous membrane.
Alzheimer's Disease
A progressive disease of the middle-aged and elderly, characterized by loss of function and death of nerve cells in several areas of the brain, leading to loss of mental functions such as memory and learning. Alzheimer's disease is the most common cause of dementia.
Premenstrual Syndrome
PMS consists of various physical and/or emotional symptoms that occur in the second half of the menstrual cycle, after ovulation. The symptoms begin about midcycle, are generally the most intense during the last seven days before menstruation and include: acne; backache; bloating; fatigue; headache; sore breasts; changes in sexual desire; depression; difficulty concentrating; difficulty handling stress; irritability; tearfulness.
Pharmacological
Involving the use of drugs.
Milligram
(mg): 1/1,000 of a gram by weight.