Zinc, a naturally occurring mineral found in food, is vital to a person's health. True, consuming too much of it can lead to adverse outcomes, like intestinal distress, vomiting, and a rash; but deficiencies are equally problematic. New research published in the British Journal of Nutrition suggests even a minimal or short-term zinc deficiency can lead to virtually undetectable damage.

According to the World Health Organization, zinc deficiency affects about a third of the world's population, and it is responsible for about 16 percent of lower respiratory tract infections, 18 percent of malaria cases, and 10 percent of diarrheal disease. Prior research has indicated it can also increase risk for systemic inflammation, breastfeeding problems, organ damage, and even death. While acne and rashes, poor neurological function, and thinning hair are signs of trouble, the start of zinc depletion is asymptomatic and often goes unnoticed.

An animal study led by Daniel Brugger of the Technical University of Munich investigated the effects of short-term deficiency and any resulting changes in digestive capacity. Brugger and his team fed 48 piglets a corn and soybean meal with adequate zinc supply for two weeks before randomly assigning them to eight different dietary transition groups. Once in their groups, pigs were fed a diet containing different amounts of zinc in order to develop early-stage zinc deficiency.

Researchers noticed that zinc depletion onset occurred without any visible symptoms, but small changes could be seen in the liver and in the blood. During the early stages, the piglet’s body tried to absorb zinc more efficiently at the same time reduced pancreatic zinc excretion. Researchers defined the pancreas as the “control center for food digestion and energy homeostasis in the body," an essential organ that pumps zinc into the gastrointestinal tract in order to maintain a consistent zinc level. Pancreatic zinc excretion is reduced when an organism is depleted of zinc, which is to say it's an important part of the digestive system.

"We proved that there is a direct correlation between the amount of digestive enzymes inside the pancreas and zinc levels in the organism as a whole," Brugger said in a statement. "Even short intervals of zinc deficiency in the diet should therefore be avoided. Given the similarities between a pig's organism and the human organism, we may draw the following conclusion when applying our results to the human body: an egg or two more once in a while can do no harm."

Clinical zinc deficiency also reduced the test animals' appetite. Zinc attaches to other enzymes in the body, including ones in your stomach that help break down food; a reduction of zinc will interrupt the digestion system. Brugger suspects the loss of appetite may be due to the “accumulation of undigested food inside the gastrointestinal tract due to zinc deficiency results in feeling less hungry.”

The National Institutes of Health recommends people get 8 to 11 milligrams of zinc each day. It's rich in seafood, meat, seeds, and cooked dried beans, peas and lentils.

Source: Brugger D, Windisch W. Subclinical Zinc Deficiency Impairs Pancreatic Digestive Enzyme Activity and Digestive Capacity of Weaned Piglets. British Journal of Nutrition. 2016.