Many people believe that zinc, an essential mineral found in almost every cell, is like a magic pill that is able to keep the sneezes away and also help with weight loss. This is probably why so many people take zinc supplements, despite the fact that most people in the United States get enough of this mineral from food.
But does science support these claims of boosting immunity and burning calories? Experts say there is some truth to these claims.
Health Benefits of Zinc
Like other essential vitamins and minerals, zinc supports overall health. “Zinc is involved in the activity of many biochemical and metabolic reactions in the body,” explains registered dietitian nutritionist Kathleen Garcia-Benson. LuckIn fact, its concentration in the body is second only to iron.
Many people believe that taking zinc supplements can help prevent or stop colds. However, studies show that there is little or no evidence that zinc can relieve cold symptoms. However, some research suggests that zinc may help shorten the duration of colds if started early.
“Research suggests that zinc lozenges may decrease the duration and severity of the common cold when taken within 24 hours of symptom onset, possibly due to zinc's ability to inhibit viral replication and support the immune system's response,” says Garcia-Benson. “However, more studies are needed to determine optimal lozenge dosage and treatment strategies.”
In addition to boosting immunity, zinc is essential for many processes in your body, including:
- DNA SynthesisZinc serves as an important cofactor for various enzymes and proteins involved in the process of DNA replication, repair, and overall genetic stability.
- wound healingZinc's role in wound healing is multifaceted, and it is essential for collagen and protein synthesis, cell proliferation, and immune function, all of which are necessary for tissue regeneration and repair.
- taste and smell sensesZinc is important for the ability to taste and smell. Zinc deficiency can adversely affect these senses.
- Growth and developmentZinc is important for human development during pregnancy, childhood and adolescence.
Can zinc boost metabolism?
Zinc plays an integral role in metabolic function. Research shows that it is essential for the proper functioning of lipid and glucose metabolism, regulating insulin expression and production.
However, when it comes to zinc’s ability to boost metabolism, findings are unclear.
A 2019 study found that zinc supplementation along with a restricted calorie diet had positive effects on reducing body weight and body mass index (BMI), as well as reducing appetite in people with obesity.
Garcia-Benson takes a different view.
“Zinc is important for supporting a variety of metabolic processes; however, it does not boost metabolic rate in the sense of increasing metabolism or burning more calories,” she says.
“There is no strong evidence that zinc increases metabolism above its natural levels in individuals who are not deficient. So while zinc is important for a healthy metabolism, it is not going to directly increase metabolic rate except in a deficiency.”
Side effects of excess zinc
As the saying goes, “too much of a good thing” is not always good. Some of the side effects of excessive zinc intake include gastrointestinal symptoms (nausea, vomiting, diarrhea, stomach pain).
“We want a healthy immune system, but not an 'increased' over-reactive system,” says Garcia-Benson. “An excess of zinc will not cause it to become overactive; however, there are other side effects of too much zinc.”
She adds, “Excessive zinc intake may decrease magnesium absorption and lead to copper deficiency. Although zinc is needed for a healthy immune system, there comes a point when this requirement is met and taking more zinc will not enhance the immune system's response.”
Zinc toxicity will pass once excessive intake is reduced. But some people may still experience long-term side effects from taking too much zinc, such as a decrease in the immune system.
Although zinc plays a vital role in the overall function and performance of the body, it is important to consume it in limited amounts.
How much zinc do you need?
The daily recommended dietary allowance is 8 mg for women and 11 mg for men.
Supplements are most useful for some people, but people can also easily meet their recommended requirement by including zinc-rich foods in their diet.
“If you're taking a supplement on a regular basis, track your food intake for a week to see if it's really needed,” Garcia-Benson suggests.
How to Get Zinc Through Food
Although zinc is available as a supplement in the form of pills and lozenges, it is also found in many foods and beverages.
“Oysters, red meat, poultry, fish, legumes, nuts, seeds, dairy, whole grains, and fortified breakfast cereals are excellent sources of zinc,” says Garcia-Benson. “In general, zinc intake is well correlated with protein intake.”
She adds, “3 ounces of cooked lean meat provides about 9 milligrams of zinc; 1 cup of yogurt provides about 2.2 milligrams of zinc, and half a cup of chickpeas or 1 ounce of walnuts provide about 1 milligram of zinc.”
Research shows that the amount of zinc absorbed from food ranges from 5% to more than 50%, depending on the amount of plant-based foods in the diet.
Who needs more zinc?
“Certain people are at higher risk for zinc deficiency, including those who have had gastrointestinal surgery (including weight loss surgery), those with ulcerative colitis, Crohn's disease, vegetarians, women who are pregnant or breastfeeding, those with sickle cell disease, and infants 6 months or older,” Garcia-Benson says.
Some common symptoms of zinc deficiency are:
- Delayed wound healing
- loss of appetite
- Decreased taste
- Immune deficiencies
- Hair loss
- Increase in night blindness
- Diarrhea
The Bottom Line
Zinc helps you maintain a healthy immune system. It has been proven to reduce the severity and duration of colds, but cannot cure them. Zinc is also important for metabolic function, but don't count on it helping you lose weight instantly.
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