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Zinc lozenges are a popular cold remedy, but this unheralded mineral can do so much more, including the following:
- Zinc is essential for a healthy immune system, which helps ward off colds and other illnesses. Zinc plays a key role in healthy cell division, which helps protect against cancer.
- In combination with other antioxidants, zinc protects the eyes against blindness from age-related macular degeneration.
- Zinc is used to treat diarrhea in children and to treat Wilson’s disease, a genetic disorder that leads to very high, life-threatening levels of copper.
- Zinc is an antioxidant that reduces chronic inflammation and may protect against atherosclerosis.
Signs You Need More Zinc
Older people and anyone whose digestion is sub-optimal may not absorb adequate zinc. In addition, a shortfall is more likely among people who don’t eat animal foods. Here are 16 signs of zinc deficiency (and/or conditions related to low zinc):
- Frequent colds or other infections
- Hair loss
- Loss of taste and smell
- Stunted growth in children
- Attention disorders in kids
- Poor mental function
- Diarrhea and IBS
- Adrenal issues
- Skin lesions (e.g., acne, eczema)
- Loss of appetite
- Hair loss
- Slow healing of wounds
- Pica (eating dirt)
- Eating disorders (e.g., bulimia, anorexia)
Related: Eat Your Zinc
Studies have found that conventional medications for heartburn and high blood pressure deplete zinc. High doses of the mineral may be necessary to restore healthy levels and should be taken under the supervision of a health professional.
Heartburn drugs reduce levels of stomach acid and this, in turn, impairs the absorption of zinc and other nutrients. One study compared effects of 26.2 mg of zinc in supplements, twice daily, in healthy people and those taking proton pump inhibitors such as Prilosec and Prevacid. Compared to the drug-free, healthy group, those taking heartburn drugs absorbed less than one-third of the mineral.
Two types of blood pressure drugs—thiazide diuretics and ACE inhibitors—increase excretion of zinc. Loss of taste can be a side effect of ACE inhibitors, and a study found that people who experienced the most loss of taste had the lowest zinc levels. Among ACE inhibitors, the greatest zinc depletion was seen with captopril (also sold under the brand Capoten).
Top Zinc Foods
Oysters are the best food source of zinc. Beef, lobster, pumpkin seeds, pork, chicken, and yogurt are also good sources of the mineral.
Try our zinc-rich Hawaiian Spirulina Trail Mix Bars.
How to Benefit from Zinc
For overall health, the recommended daily allowance (RDA) of zinc is 8 mg for women (increased to 11 mg during pregnancy and 12 mg when breastfeeding) and 11 mg for men. Older adults with reduced ability to absorb nutrients may need more. The safe upper limit for healthy people is 40 mg daily, but anyone taking a medication that depletes zinc may need higher doses under the supervision of a health professional.
High doses of zinc can lead to a copper deficiency. However, most multis provide enough copper with zinc. In supplements, zinc comes in different forms—chelated zinc, zinc orotate, and zinc picolinate are thought to be among the best-absorbed forms.
Zinc can reduce the effectiveness of antibiotics or penicillamine (a rheumatoid arthritis drug) if it’s taken at the same time as the drugs. To avoid this, take zinc 4–6 hours before the antibiotic or 2 hours afterward. With penicillamine, take zinc 2 hours before or after the drug.
How to Treat a Cold Using Zinc
Zinc lozenges fight cold viruses by coating the inside surface of your mouth and throat. Let lozenges dissolve instead of chewing and swallowing them. Studies show that zinc acetate or zinc gluconate lozenges can shorten a cold by 2–3 days when taken every couple of hours, starting within 24 hours of the first symptoms. Aim for a daily total of 80–100 mg of zinc, which is a safe dose for treating a cold.
Testing for Zinc Levels
There are a few tests, including a home taste test, that can help you determine whether or not you are lacking in zinc. To learn more, we like this comprehensive list of zinc diagnostic tests.