Ask Dr. Locke

I’ve heard that melatonin can help with jet lag.  Is there any evidence to support this claim?

Melatonin is a hormone produced by the brain that is involved in the regulation of circadian rhythms.  Several studies in humans have concluded that in about 50% of subjects, melatonin can significantly improve jet lag by reducing the number of days to establish a normal sleep pattern, reducing sleep latency time (amount of time to fall asleep) and decreasing daytime fatigue.  The dose for jet lag is 5 mg taken orally at bedtime for 1 week beginning 3 days before the flight. Melatonin does not require a prescription and can be found at your local drugstore. 

Melatonin is generally well tolerated with side effects that may include headache, dizziness, drowsiness and GI complaints.  It should be avoided in people with liver impairment or who are immunosuppressed.

I am suffering from depression but I am reluctant to take prescription medications.  Is St. John’s wort effective?

There is evidence that St. John’s wort may be as effective as tricyclic antidepressant drugs for the short term treatment of mild to moderate depression, but it is not clear if St. John’s wort is as effective as Selective Serotonin Reuptake Inhibitors.  It is generally well-tolerated with common adverse effects including insomnia, restlessness, GI upset,and dizziness.  The usual dose is 900-1800 mg divided into 3 times daily.

There are two major drawbacks that may limit the use of St. John’s wort.  The first is that to be effective, it needs to be taken three times a day, so compliance may be an issue.  The second caution is that St. John’s wort interacts with several common medications either increasing or decreasing their levels.  Therefore, it is necessary to always consult with your physician before beginning any over the counter supplement.

Can Ginkgo biloba improve my memory?

At the present time, there is no definitive data that ginkgo enhances memory in healthy subjects although studies show some promising early evidence .

On the other hand, in persons with early Alzheimer’s dementia and multi-infarct dementia, studies report that ginkgo can stabilize or improve several measures of cognitive and social functioning. However,   gingko has not been directly compared with conventional treatments. 

The recommended dose for dementia is 120-240 mg/day in divided doses.   Gingko can interact with antiplatelet and anticoagulant medication and therefore increase the risk of bleeding, so it should not be used without consulting your physician. 

What’s the best way to lose and keep weight off without giving up carbohydrates?

The best way to lose weight is by reduction of daily caloric intake and increasing exercise.  However, to maintain weight loss, modification of eating habits is essential.  In addition to reducing saturated and trans fat in your diet, studies show that substituting “good “ for “bad” carbohydrates will help to maintain weight loss.  Good carbohydrates are whole grains, whole fruits, whole vegetables, beans, legumes and nuts. Bad carbohydrates are refined grains such as white flour, white rice and table sugar.

Will Vitamin C prevent the common cold?

A:  Taking Vitamin C for the prevention of colds or for decreasing the duration and severity for colds has been widely studied since the 1970’s.  Despite its widespread use, experts agree that the evidence does NOT support that taking high doses of Vitamin C (> 200 mg) prevents or significantly changes the course of a common cold.

 

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