Zinc Acetate Lozenges
A recent analysis of randomized, placebo controlled trials of zinc lozenges, recently published in the British Journal of Clinical Pharmacology, showed that zinc acetate lozenges may reduce the duration of the common cold by nearly 3 days. The common cold is an infection caused by many different viruses.
The effect of zinc lozenges was not changed by allergy status, smoking, symptom severity, age, sex or ethnic group. High dose zinc acetate lozenges shortened the duration of common cold symptoms of nasal discharge by 34% nasal congestion by 37%, scratchy throat by 33% and cough by 46%. Zinc lozenges also shortened the duration of muscle aching by 54%. However, there was no evidence of zinc effect on headache or fever. Because high doses of zinc can cause side effects such as nausea, dosage of lozenges should not exceed 100 mg per day. Most zinc acetate lozenges have 18.75 mg of zinc; taking two daily is helpful for most people. Simply taking supplemental zinc in pill form may not have the same effects, because it is the zinc dissolved in saliva that is believed to be effective.
According to an updated review of vitamin C and the common cold, vitamin C halved the incidence of contracting the common cold among people undergoing physical stress, such as marathon runners, or people working in the cold. Vitamin C may also reduce bronchoconstriction (asthma-like symptoms) caused by exercise. Some, but not all studies, indicate that taking vitamin C shortens the duration of a cold.
A recent report from the University of Colorado School of Medicine looked at the use of vitamin D among older, long-term care residents of nursing homes. There was a 40 percent reduction in acute respiratory illness among those who were given 100,000 IU of vitamin D per month (averaging 3,300-4,300IU daily) compared to those receiving 12,000 IU per month (averaging 400-1000 units daily). However, there were more falls, although not more fractures, in patients receiving the higher doses. Further study will look at giving patients a daily dose of vitamin D rather than very high dosages monthly. Numerous other studies of vitamin D have shown that supplements of D have lowered the incidence of respiratory infections in children and adults. Most studies have shown that a blood level of at least 30 ng/ml of vitamin D is desirable. Check with your primary care provider for a test of your vitamin D blood level. In the meantime, taking a vitamin D supplement of 1000 IU is probably safe and desirable for most people, especially in the winter months when sun exposure is minimal at our latitude. Have some zinc acetate lozenges on hand. Keep up your vitamin C intake with citrus fruits and other raw fruits and vegetables, or take a supplement.
Consider taking a probiotic supplement as well – a study from the University of Medicine and Dentistry in New Jersey showed that students taking a probiotic supplement had a shorter duration of colds and symptoms that were 34% less severe. Include fermented foods such as yogurt in your daily diet as well.
Finally – if you haven’t had a flu shot this year – it’s still not too late. Go for it!
Sadja Greenwood, MD, MPH back issues on this blog