Overdoing it when trying to prevent a cold or the flu can actually make things worse.  

Zinc is an essential nutrient for protecting our immune systems from viruses and bacteria, helping wounds to heal, and making protein and DNA in the body. It’s even important for providing us with a proper sense of smell and taste.

Zinc can be obtained from oysters, meat, poultry, and some plant-based foods. It’s also a popular supplement, especially during flu season. While it’s crucial to make sure we get enough of this nutrient—11mg per day for men and 8mg for women—consuming too much has serious consequences.

Flu-Like Symptoms

Too much zinc can actually make you feel like you have the flu, with symptoms like nausea, fever, vomiting, and coughing. If you regularly consume foods with high levels of zinc, such as meat and fortified cereals, there is no need to up your zinc intake during flu season, as it can produce this reverse effect.

Diarrhea and Abdominal Pain

This is a common symptom for those who have consumed too much zinc, and one study showed it was linked to 40 percent of participants who took a zinc supplement to fight a cold. Diarrhea is not only uncomfortable, but it can be dangerous when you’re sick, as it dehydrates you even more.

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Copper Deficiency

The presence of too much zinc in the body prevents it from properly absorbing copper, an essential mineral for creating red blood cells. Copper deficiencies can lead to anemia, which inhibits energy levels, concentration, and breathing ability. Too little copper in the body can also cause numbness or pain in your limbs.

Zinc and Antibiotics

Taking an oral zinc supplement can inhibit certain antibiotics from fighting off illness. Tetracycline and quinolone, popular antibiotic options, need to be taken several hours after a zinc supplement to minimize the effect. However, you might be better off ditching the supplement for a few weeks to make sure the antibiotic can do its job.

The bottom line: Consuming a variety of whole, healthful foods is always the best way to get enough of the nutrients you need. Supplements should be just that—a supplement to a nutritious diet, and should never be considered as a replacement for healthy food.

If you do want to take a zinc supplement, it’s important to note they are often sold in large doses, and don’t need to be taken every day. More importantly, make sure you’re eating lean meats, whole grains, nuts, and beans to help your body produce the zinc it needs to keep you strong and healthy this flu season.