My personal affair with melatoninBy Rafael Castillo M.D.
Philippine Daily Inquirer
Many have been asking why I have been taking a melatonin supplement nightly for around 20 years now. I started taking it in the early ’90s, not because of its sleep-enhancing benefit, but for its immune-system boosting effect.
I used to have severe bouts of allergic rhinitis when I was young. It has reached a point when I thought I would have to live with it the rest of my life. It was not the seasonal type; I had it all-year round. Mornings and evenings had to be endured with teary and itchy eyes, a runny and equally itchy nose. My handkerchiefs would be soaked wet with clear mucus by mid-morning.
Several times a year, bacterial infection would superimpose on my allergic rhinitis and this would progress into upper or lower respiratory tract infection. I must have taken all sorts of antihistamines and some steroids then, but the antihistamines made me drowsy all day and so I stopped taking them. I decided I could be more functional with my runny nose and teary eyes, than my drooping eyelids.
I came upon a published study showing the immune-system-boosting effect of melatonin. Of course, its sleep-enhancing effect was already well known since then. I tried to research if there were specific studies on the effect of melatonin in allergic rhinitis but I could not find any then. I’m not sure if there are already available studies now. I have been encouraging my ENT (Ear, Nose and Throat) specialist-friends to conduct a local study.
Although there were no specific data on allergic rhinitis, it seemed to me then that if melatonin could help those with markedly suppressed immune systems, allergic rhinitis should be a walk in the park for it. So I started taking 3-mg capsules of Melatonin-T nightly. It was already available then as an over-the-counter dietary supplement in Mercury and other drugstores. Lately, I’m taking Sleepwell Melatonin, but it’s just the same preparation as Melatonin-T.
There was not much change in the first four weeks in my allergic rhinitis symptoms, except that I had better sleep. I was already tempted to discontinue it. By the second month, the severity of my allergic rhinitis gradually lessened. After four months or so, my allergic rhinitis was practically reduced to an occasional transient stuffiness of the nose on waking up. After about a year of being symptom-free, which I have never experienced in decades, I decided to see if I could already stop taking melatonin. I would be okay for a week or so, but after that, the previous symptoms would slowly recur. So since then, I decided to take it religiously every night.
I still browse the scientific literatures from time to time to check on any long-term adverse effects of melatonin since I’ve been taking it for quite a while already and planning to do so for life. I’m glad to note that there was none reported. In fact recently, many cancer centers abroad are prescribing melatonin in mega-doses (20 to 50 mg) as a beneficial anticancer supplemental therapy in patients receiving chemo- or radio-therapy for various forms of cancer.
Melatonin also been demonstrated to have anticancer properties, not only by directly helping prevent the growth and spread of cancer cells but also by reducing the side effects, particularly bone marrow suppression, of common anticancer drugs (chemotherapy) and radiation treatments.
In highly symptomatic cancer patients, in whom the disease has already spread, melatonin has been shown to alleviate numerous cancer symptoms, and inhibit the development of new tumor blood vessels (tumor angiogenesis). This last benefit can help prevent the cancer from spreading further.
Retard tumor metabolism
One interesting finding is that melatonin can retard tumor metabolism and development by lowering the body temperature—as a natural inducer of hypothermia. Its antioxidant properties also hinder tumor cells from causing damage to normal cells. It also limits oxidative damage to cellular components caused by various anticancer treatments.
Melatonin supplementation, given at a dose of 20 mg/day, has been shown to be beneficial in the supportive care of even advanced and end-stage cancer patients by enhancing immune function; reducing tissue wasting or cachexia, weight loss, fatigue, weakness and depression; and improving quality of life and survival rate. In cancer patients requiring surgery, melatonin has also been shown to improve wound healing.
Chemotherapy-induced side effects such as anemia, lymphocytopenia and thrombocytopenia, anorexia and vomiting have been reduced. It also helps in reducing cancer pain (including bone pains).
Women with estrogen-receptor-positive breast cancer have also been shown to have low plasma melatonin levels. These women can benefit a lot from melatonin supplementation. Melatonin has been demonstrated to inhibit human breast cancer cell growth and reduce the invasiveness of breast cancer cells. Women who work night shifts like nurses and factory workers are at increased risk of developing breast cancer because of lowered melatonin levels, since the secretion of this natural hormone usually occurs at night time, stimulated by darkness.
It’s amazing what a simple substance like melatonin can produce. Aside from its sleep-enhancing and anticancer effects, it also has a lot of other health benefits which are also backed up already by scientific data.
I usually advise younger physicians not to believe any drug or product which claims to have multiple benefits. Too good to be true, I would tell the doctors. Well, I guess melatonin may be an exception.