Melatonin Shown to Prevent Transition to Alzheimer’s disease

James Meschino DC, MS, ROHP
Experimental investigation has shown that melatonin blocks the build-up of beta-amyloid plaque (a protein-like substance that is a hallmark feature of Alzheimer’s disease). Other studies show that Alzheimer’s patients tend to have lower melatonin levels than non-Alzheimer’s patients. Based on this evidence clinical studies have been performed in recent years to test the value of administering melatonin to patients with mild cognitive impairment (MCI). MCI is the stage of memory loss and functional brain capacity decline that is the forerunner to the development of full-blown Alzheimer’s disease.

To date three separate studies have shown that melatonin supplementation significantly reduced the transition from MCI to Alzheimer’s disease. One study used a dosage range of 3-9 mg, one hour before bedtime, whereas the two other studies reported good results using an evening dosage as low as 1 mg, and no higher than 6 mg.

This research is more compelling when you consider the fact that melatonin levels begin to decline during our teenage years, but by age 40 they have reached a low enough level to often trigger sleep disturbance problems. The pineal gland in the brain normally secretes melatonin in the late evening hours (darkness is a trigger), which helps to induce sleep. As such, lower age-related melatonin levels in the brain are a major cause of insomnia and interrupted sleep problems. Many people take melatonin supplementation because it helps them fall asleep, as a natural sleep-aid. However, melatonin is also a powerful brain antioxidant, and its ability to quench free radicals in this role, and suppress the build-up of beta-amyloid plaque are the ways it is purported to reduce transition from MCI to Alzheimer’s disease

The Aging Brain and Mild Cognitive Impairment
We have known for many years that the brain of elderly people shows atrophy (shrinkage). More recently we have realized that atrophy occurs even in cognitively healthy subjects, but is much more accelerated in patients with Alzheimer’s disease. Studies show the following:

• An intermediate rate of atrophy is found in people with mildMCI
• People over 60 yrs without MCI normally have brain shrinkage of approximately 0.5 % per year.
• Individuals showing MCI normally show a brain atrophy rate that is twice as fast, at approximately 1% per year
• Alzheimer’s patients can lose 5 % of brain volume per year

The Oxford project showed us that the only proven way, thus far, to slow brain shrinkage after age 60 is with B-vitamin supplementation. In addition to a B-50 complex, it may also be useful to include melatonin supplementation based on recent clinical trials, especially if mild cognitive impairment is already present.

Melatonin Dosage
To improve sleep quality begin with no more than 500 mcg of melatonin, one hour before bedtime. If that is not sufficient then increase the dosage to 1 mg (1000 mcg) or two capsules. Slowly increase the dosage until you find the dosage that gives you a good night’s sleep and allows you be refreshed the next morning. For individualswith MCI higher dosages may be more appropriate (3-9 mg) to prevent the transition to Alzheimer’s disease, as noted above. You should be monitored by a physician if taking any dosage above 3 mg.

Signs and Symptoms of MCI:

You, your family or friends notice a greater tendency than normal for you to:

• forget things
• forget important events such as appointments or social engagements.
• lose your train of thought or the thread of conversations, books or movies you are reading or viewing
• feel increasingly overwhelmed by making decisions, planning steps to accomplish a task or interpreting instructions.
• have trouble finding your way around familiar environments.
• bemore impulsive or show increasingly poor judgment.
• Your family and friends notice any of these changes