Zinc is a simple mineral with critical roles in maintaining health. It supports proper function of your immune system, plus helps form key building blocks of testosterone for men.
Want to know more about how zinc benefits health? Read on for our most important takeaways from the nutritional research.
Research
Zinc benefits
1. Zinc is a critical trace mineral for hormone production
It is a vital mineral that your body uses for everything from boosting its immune system to producing hormones. Its two main uses as a supplement are attacking infections, like the common cold, and keeping your testosterone at a healthy level.
2. Zinc may help you recover quicker from the cold
On the illness front, zinc is a popular way to boost your immunity against getting sick, and a way to decrease your recovery time if you do come down with a mild illness.
One study among infant and preschool children found that supplementing a child’s diet with 10 mg of zinc could decrease the incidence of getting sick by 45% (1).
3. Zinc might not always work for illness
When it comes to speeding recovery from illness, zinc might have an effect, but it’s not very big.
A 1989 study by researchers at the University of Pennsylvania School of Medicine found a 13% improvement in cold symptoms after 7 days, but noted that this difference was pretty small, and not everyone benefited (2).
4. Zinc can support high testosterone levels
Having healthy testosterone levels is important for men, who suffer from fatigue, loss of muscle mass, and loss of virility when they have low levels of testosterone in their blood.
This is a natural consequence of aging, and can be counteracted at least partially by taking a zinc supplement. One study found that zinc supplementation doubled testosterone levels (3)!
5. Restricting zinc levels in young men decreases testosterone
The same team of scientists also tested the converse of this experiment—they fed a group of young men a zinc-restricted diet over the course of 20 weeks, and observed exactly what we’d expect: concentrations of testosterone in the blood plummeted by a factor of four.
What this tells us is that zinc is critical for keeping your testosterone levels high. Fortunately, taking a zinc supplement is both inexpensive and easy to do.
Zinc side effects
Zinc, as a natural mineral that’s a part of any standard diet, is pretty slim when it comes to short-term side effects.
Chronic zinc overload could increase prostate cancer risk. However, there is some concern that chronic zinc overload can increase your risk for prostate cancer.
According to a scientific brief published in 2003 in the Journal of the National Cancer Institute, men who took over 100 mg of zinc per day had about twice the normal rate of prostate cancer compared with men who took less than 100 mg per day (3).
An important point is that this is supplemental zinc intake, not total zinc intake.
It would take some very intense zinc supplement dosing to reach 100 mg per day. Remember, the recommended daily intake is only 15 mg per day, so even several times higher than that should still be safe.
Too much zinc can interfere with copper absorption. Additional research also suggests that taking too much zinc can interfere with your ability to absorb copper, another essential trace element (4).
Zinc dosage
Ultra-high doses are not needed. Happily, there’s no real reason to take ultra-high zinc dosages, because the scientific research shows that much more moderate does are plenty effective.
Aim for 10-30 mg per day. The research study on elderly men, for example, showed that a dose of only 30 mg of supplemental zinc per day (200% of your recommended daily intake) can double your testosterone levels if you are marginally zinc deficient.
Other research uses similarly small values (5). Based on this information, a supplemental dose of at least 10 mg but no more than 30 mg per day seems appropriate.
Zinc benefits FAQ
Q: How much zinc should you take per day to increase testosterone?
A: Research in older men suggests that a single 30 mg dose of zinc is sufficient to boost testosterone. If you are younger (say, under 40 years old), zinc intake might not be as much of an issue for you, and so starting with a dose closer to 15 mg might be easier.
Based on the research done so far, and based on what we know about the potential side effects of zinc at higher dosages, there is no reason to take more than 30 mg of supplemental zinc per day.
Q: Is 50 mg of zinc too much?
A: For most people, the maximum necessary dosage of zinc is 30 mg. Research has found that even among elderly men who are zinc deficient, a dosage of 30 mg is enough to restore androgen function to a satisfactory level in fairly short order.
Studies on using zinc to prevent or speed recovery from upper respiratory infections like the common cold use an even lower dosage, typically no more than 10 mg.
While some supplements offer 50 mg and higher doses, you should not take these unless you’re under a doctor’s orders, since at high doses, zinc can crowd out copper for absorption in your intestines, and increase levels of LDL (“bad”) cholesterol in your blood, while decreasing levels of HDL (“good”) cholesterol. These effects do not appear at lower dosages.
Q: What is zinc?
A: Zinc is an element, and in its natural form, is a pale gray metal. When taken as a supplement, zinc is always in a salt form, when it’s paired with another molecule that facilitates easy absorption by your body.
In our rankings of the top zinc supplements on the market, we only include those that had a water-soluble form of zinc. This makes zinc much more easily absorbed. Inside your body, zinc contributes to a huge number of biochemical reactions.
Its health effects are particularly important for men, who rely on adequate levels of zinc to keep their testosterone levels high.
Q: What’s the right dosage of zinc for children?
A: In research on using zinc to treat the symptoms of the common cold, scientists typically use no more than 10 mg of zinc.
Often, this is delivered using a lozenge or cough drop for maximum efficacy. Since children are smaller, they do not need nearly as high of a dosage as an adult.
Moreover, the dosage that appears necessary to reduce the duration of a cold is not as high as the dosage needed to reverse zinc deficiency in adults.
Q: Can you overdose on zinc?
A: The medical literature has described cases of serious and sometimes fatal zinc overdoses, but these have all happened in the context of intravenous administration of zinc.
One case study reports on an otherwise healthy male who consumed over 500 mg of elemental zinc at once who had severe nausea and vomiting for about half an hour, but who suffered no long-term health effects (6).
While it’s theoretically possible to overdose on zinc, it’s not going to happen accidentally. The more important risks are those of zinc toxicity, which can happen when you take a lot of zinc on a regular basis.
Regular consumption of too much zinc in the form of a zinc supplement can cause a copper deficiency, or alter your HDL and LDL cholesterol levels.
Related: Our best zinc picks
Summary
Zinc is a mineral supplement that’s critical for immune and hormone function. Older men are particularly vulnerable to zinc deficiency, so they ought to consider taking a zinc supplement if their levels are low.
Taking zinc, especially in lozenge form, soon after contracting a cold could speed recovery, so it’s helpful to have zinc lozenges handy for when you feel an upper respiratory infection coming on.
