The common cold is a top reason for missed work and school days. Most of us have two or three colds per year, each lasting at least a week.
There's no real cure, but studies from the last several years show that some supplement containing zinc can help shorten the duration of cold symptoms by up to 40% — depending on the amount of the mineral in each dose and what it's combined with.
Zinc has an interesting back story. It wasn't even acknowledged as an essential mineral for human health until the 1970s. But that changed thanks to the work of Dr. Ananda Prasad — a 91-year-old doctor who, decades ago, had a hunch that led to a better understanding of zinc's role in immunity.
Back in the 1960s Prasad was studying a group of young men in Egypt who had not grown to normal heights and remained underdeveloped in other ways, too. Prasad wondered if the problem might be a lack of zinc.
When Prasad gave them zinc supplements, the men grew significantly taller.
"I couldn't believe it," he says. Prasad had never expected such significant growth.
Some scientists challenged his findings, at the time, questioning the idea that zinc deficiency could even occur in humans. "It was controversial," Prasad says.
But he pressed on with his research and began to document the ways zinc influences immunity.
Eventually, in the 1970's, the National Academy of Sciences declared zinc an essential mineral, fundamental to many aspects of cell metabolism. NAS established a recommended daily allowance, which is the daily amount that's sufficient for good nutrition. (Most of us today get plenty of zinc from foods such as beans, nuts, whole grains and fortified cereals.)
Prasad says he felt vindicated by this action. "Absolutely," Prasad told us from his home in Michigan, where he's a researcher and professor at Wayne State University School of Medicine in Detroit.
What came next in his career may be just as surprising. Prasad had demonstrated that zinc had an effect on immunity — so he figured that it might help against a ubiquitous scourge — the common cold.