Introduction

Zinc is an essential mineral that plays a crucial role in various physiological processes within the body. It plays a fundamental role in supporting our immune system, wound healing, and skin health (1). Zinc also aids in maintaining our sense of taste and smell, and zinc deficiencies have been shown to reduce these senses (2).

The human body cannot naturally produce or store zinc, therefore an adequate amount must be obtained from the diet or zinc should be supplemented with on a regular basis. Some data suggest that at least one in five people are at risk of zinc deficiency, largely due poor dietary intake and due to phytates in the diet that inhibit zinc absorption (3). Here, we provide a detailed review of zinc’s health benefits, its main food sources, common groups who may be at risk of deficiency, and the benefits of supplementation.

Benefits of Zinc

Immune Support

Zinc is well known for supporting the immune system. It contributes to the development and function of immune cells, including T cells and B cells, which play a vital role in fighting off infection (4). Zinc is also involved in the production and activation of white blood cells, which are essential for recognizing and destroying pathogens. Research suggests that zinc supplementation can help reduce the severity and duration of the common cold and other respiratory infections, making it a popular remedy during cold season (5).

Wound Healing

Zinc plays an important role in various stages of the wound healing process such as collagen synthesis, which is necessary for the formation of new connective tissue repair (6). Zinc also promotes cell proliferation and migration to help facilitate the formation of new tissue in the wound area.

Skin Health and Inflammation

Zinc helps maintain healthy skin, ranging from regulating oil production to protecting against oxidative damage. It contributes to the regulation of sebum production, which helps keep skin moisturized and helps prevent acne formation (7). Zinc also has antioxidant properties, protecting the skin from oxidative damage caused by free radicals and environmental stressors (8). Lastly, zinc’s anti-inflammatory properties help soothe irritated skin and can reduce redness associated with conditions like eczema, psoriasis, and acne (9). By reducing inflammation, zinc may also alleviate symptoms associated with inflammatory conditions such as arthritis, inflammatory bowel disease, and asthma.

Food Sources of Zinc

Animal-based products such as shellfish, meat, poultry, and fish contain the highest amounts of zinc, though oysters stand out as one of the highest natural sources of zinc compared to other foods. In general, animal-based zinc sources contain zinc in a form that is more readily absorbed by the body (10).

Zinc is present in various plant sources as well such as legumes, nuts, seeds, and whole grains. Zinc found in plant-based foods is not absorbed as well as from animal foods due to phytates present in plant foods that bind to zinc and inhibit its absorption in the intestines (11). Additionally, some plant foods contain other substances that can further reduce zinc absorption such as oxalates and tannins (12).

Incorporating a variety of the foods mentioned above in the diet is essential for maintaining zinc levels and supporting the immune system. If you adhere to a specific diet such as vegetarianism or veganism, include a variety of plant sources of zinc in your diet to ensure you’re getting enough of the nutrient.

Risks of Deficiency

Certain groups of people are at a higher risk of zinc deficiency due to factors such as poor dietary intake and lack of absorption. Vegetarians and vegans, pregnant women, and individuals with gastrointestinal disease are examples of people with a higher risk of deficiency for the following reasons (13):

Vegans and vegetarians: Vegans and vegetarians may have difficulty obtaining zinc from diet alone since zinc is predominantly found in animal-based foods. Although zinc is also found in plant-based sources, the presence of compounds such as phytates bind to zinc and can inhibit its absorption by the body.

Pregnant women: Pregnancy imposes higher zinc requirements to support fetal growth and development. This increased demand for zinc during pregnancy may compete with maternal zinc stores and dietary intake, leading to a deficiency that is associated with low fetal birth weight (14).

Individuals with gastrointestinal disease: Conditions such as Crohn’s disease, ulcerative colitis, and celiac disease can impair the absorption of nutrients, including zinc, due to inflammation, damage to the intestinal lining, or deficiencies in digestive enzymes (15).

Zinc Supplementation

Benefits of Supplementation

Zinc is well known for its role in supporting immune function and is commonly used as a popular supplement during cold seasons. A systematic review that analyzed the effectiveness of zinc supplementation in reducing the duration and severity of the common cold found that supplementation may shorten the duration of symptoms when taken within 24 hours of symptom onset (16).

It may be difficult to obtain sufficient zinc from diet alone, especially in some individuals such as vegetarians and vegans who eat primarily a plant-based diet. Not only is low dietary intake associated with limited consumption of zinc-rich foods like meat and seafood, but also due to the presence of absorption inhibitors in plants such as phytates. Zinc supplementation can be helpful to meet daily zinc requirements and support overall health. The plant-based essentials contains a bioavailable form of zinc and is third-party tested. It is designed for vegans and vegetarians who are looking to supplement their diets with the nutrients they need most and can be purchased here.

Risks of Too Much Zinc

Some risks exist from supplementing with too much zinc. Too much zinc can lead to adverse effects such as headaches, dizziness, or nausea (17). In addition, since zinc competes with copper for absorption in the body, prolonged zinc supplementation can lead to a copper deficiency (18). Some therefore recommend supplementing with copper in addition to supplementing with zinc. The optimal zinc to copper ratio in a supplement can be found in the plant-based essentials.

Factors to Consider When Choosing Zinc Supplements

Zinc supplements can vary in quality and effectiveness. When selecting a supplement, keep these factors in mind:

1. Look for the most bioavailable form: Look for supplements that are easily absorbed by the body, such as zinc picolinate, as each form of zinc has a different absorption rate (19). Zinc oxide, for example, is poorly absorbed (20).
2. Read the ingredients: Some supplements may contain unnecessary additives or fillers that you may wish to avoid. In addition, if following a vegan diet, avoid ingredients such as gelatin and lactose to ensure it is vegan-friendly.
3. Ensure the supplement is third-party tested: Look for zinc supplements from reputable brands that undergo third-party testing for quality and purity.
4. Consult a healthcare professional: If in doubt, seek advice from a healthcare provider or a nutritionist to make an informed decision.

Most zinc supplements are suitable for vegans, but to ensure the supplement is vegan-friendly, look for zinc supplements in the form of zinc picolinate, zinc citrate, or zinc gluconate. These forms of zinc are typically derived from plant-based sources, making them suitable for vegans.

Conclusion

Zinc stands as a vital mineral essential for various physiological functions within the body such as immune support and wound healing. While abundantly found in animal-based foods like meat and seafood, plant-based sources of zinc can also contribute to dietary intake. Despite its widespread presence in food, certain groups of people such as vegans, pregnant women, and those with gastrointestinal disease may be at a increased risk of deficiency. In these cases, zinc supplementation can help bridge nutritional gaps and support overall health.

References

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