Zinc for Immunity

Zinc supplementation might protect against colds and boost immunity in zinc-deficient individuals.

• Support immune function. Zinc is critical for the proper functioning of white blood cells and other parts of the immune system.
  
• Ward off colds. The latest research suggests that there is some truth to the belief that zinc supplements can help you get over a cold quickly.

Overview

Zinc is an essential mineral that our bodies need in small amounts to function properly. Just some of the fundamental processes zinc is involved in are protein & DNA production, cell division, and wound healing. However, zinc is better known for playing a critical role in the function of the immune system.

Indeed, many people believe that supplementing zinc can help ward off colds and other infections and illnesses. The only caveat is that zinc supplements are unlikely to do much if you already get enough zinc from your diet.

Although zinc deficiency is relatively rare in the developed world, certain populations – such as the elderly and vegetarians – do have an increased likelihood of not getting enough zinc. As such, they might see improved immune system function from zinc supplementation.

How Zinc Might Help With Immunity

Supporting optimal immune function

Zinc plays a critical role in virtually all aspects of the immune system. Zinc is needed for optimal function of the many different types of white blood cells that protect the body from illness and infection, in addition to cytokine production, phagocytosis, and other immune system processes.¹ Even mild zinc deficiency can weaken the immune system, whereas severely zinc-deficient individuals suffer from constant infections that could even lead to death as early as 25 years of age.

Antioxidant activity

Activation of the immune system results in increased generation of reactive oxygen species (ROS), which can in turn in damage immune system cells and processes. As an antioxidant compound, zinc can help neutralize this damage, indirectly improving immune system function.²

Zinc Immunity Uses & Benefits

Given it’s essential roles in the human body, zinc is supplemented to help with everything from testosterone production to vision loss. Similar to vitamin C, zinc is also commonly used to ward off cold and flu infections.

There is some scientific evidence that zinc can help with colds. In terms of boosting overall immune function, however, it seems that zinc only helps individuals with low zinc levels, such as older adults.

Research

Human Research

Human trials confirm that zinc supplementation can improve immunity in the elderly, and help ward off the common cold.

Zinc (45 mg) supplementation appears to boost the immune function of older adults

This randomized, double-blind, placebo-controlled study tested the immunity benefits of zinc supplementation in elderly participants. Fifty healthy adults (aged 55-87) received either zinc gluconate (45 mg) or placebo daily for 12 months. The trial found that the subjects had naturally lower zinc levels than younger adults, and that supplementation raised zinc levels along with a significant reduction in occurrence of infections and production of tumor necrosis factor alpha, a cytokine that promotes inflammation.

• The researchers concluded that “After zinc supplementation, the incidence of infections was significantly lower, plasma zinc was significantly higher, and generation of tumor necrosis factor alpha…was significantly lower.“⁵

Zinc supplementation may improve immunity in older adults

This study examined the effect of zinc supplementation on the immune system of older adults. Fifteen people (aged older than 70) were given zinc sulfate (440 mg) daily for month and compared to 15 supplemented individuals. The study reported significant improvement of immune function, as shown by higher number of T cells, delayed hypersensitivity reactions, and antibody response to a vaccine.

• The researchers concluded that “the addition of zinc to the diet of old persons could be an effective and simple way to improve their immune function.“⁶

Zinc (75+ mg) appears to shorten the duration of colds

This systematic review sought to explain the mixed results of 13 studies looking at zinc use for the common cold. The researchers hypothesized that the reason some studies showed no benefit was because the zinc dosage was too low. They found that all 8 studies that used high doses (75+ mg) of zinc reported a significant reduction (20-42%) in the duration of colds.

• The researchers concluded that “Many trials with daily zinc doses of over 75 mg have found significant reduction in the duration of colds.“⁷

Dosage for Immunity

• Research suggests that around 45 mg zinc gluconate or 440 mg zinc sulfate can boost immunity
• Zinc doses of 75 mg or more appear to be effective for helping with colds
• Zinc acetate may be more effective for warding off colds than zinc gluconate
• Most single-ingredient zinc supplements supply doses of 30-50 mg zinc gluconate