Zinc is a trace mineral the body needs for proper immune functioning, wound healing, and the production of cells and hormones. You can get it through food, but some people turn to zinc supplements to fill nutrient gaps or for potential benefits, such as helping with the common cold.
But how you take zinc matters: Supplementing with it on an empty stomach increases effectiveness, but may cause side effects for some people.
For optimal absorption, zinc is best taken without food, said Carla Kuon, MD, an associate professor of medicine at the University of California, San Francisco’s Osher Center for Integrative Health. Certain compounds, including calcium and other minerals, as well as phytates found in grains and legumes, can bind to zinc and reduce how much your body receives.
Specifically, taking zinc with food may lower absorption by 15% to 20%, according to Dana Ellis Hunnes, PhD, RD, a dietitian with Ronald Reagan–UCLA Medical Center and author of Recipe for Survival. That said, most people don’t need large amounts of zinc (men should aim for 11 milligrams (mg) daily and women 8 mg), so those who take supplements are likely to absorb enough even if they take them with food, she said.
For people with sensitive stomachs, intentionally taking zinc with a meal may help prevent side effects like stomach upset and nausea, Hunnes added.
Before adding zinc to your routine, experts recommend speaking with a doctor or registered dietitian to discuss what’s appropriate for your individual needs.
That said, if you take zinc without food, Kuon recommended keeping the dose at 30 mg or less, and depending on your zinc levels, limit supplementation to once or twice daily. She also suggested choosing zinc picolinate, a form that’s more easily absorbed.
Also keep in mind that high daily doses of zinc for an extended period can interfere with copper absorption, which may lead to copper deficiency and increase the risk of bone fractures or recurrent infection, Hunnes said.
Taking zinc supplements may be beneficial for people with a leaky gut or severe skin damage caused by pressure ulcers, such as bedsores, Hunnes said. You’ll also want to consider zinc supplements if you don’t get enough of the nutrient through food alone.
Certain groups are at higher risk for a zinc deficiency, including people with intestinal conditions like irritable bowel syndrome or inflammatory bowel disease, older adults, and vegans and vegetarians. Plant-based foods generally contain less zinc than animal sources like red meat, poultry, and seafood.
