Zinc is one of the most important trace elements in the body. — it is involved in over 300 enzymatic reactions, supports the immune system, skin and hair health, and plays an important role in hormone production. Yet zinc deficiency is surprisingly common, especially among athletes, vegetarians, and the elderly. In this guide, we explain why zinc is essential, how to recognize a deficiency, which zinc supplements to choose, and how to dose them correctly.
Last updated: April 2026
Why is zinc essential for the body?
Zinc is an essential mineral that the body does not produce or store on its own — meaning we need to get it from food or supplements every day. Here are the main functions of zinc:
- Immune system support — Zinc is necessary for the normal development and function of immune cells (T-lymphocytes). A deficiency significantly weakens the body’s defenses
- Skin, hair and nails — zinc is involved in collagen synthesis, cell renewal and wound healing. This is why zinc deficiency often manifests itself as skin and hair problems
- Testosterone production — Zinc is directly required for testosterone synthesis. Men who are zinc deficient often also have lower testosterone levels.
- Wound healing — zinc accelerates tissue repair and regeneration. After surgeries and injuries, the need for zinc increases significantly
- Sense of taste and smell — Zinc deficiency can cause a loss of taste and smell. This is one of the earliest signs of deficiency.
- Protein synthesis and DNA repair — zinc is important for creating proteins and protecting the genetic material of cells
- Fertility — zinc affects both male sperm quality and female ovarian function
Zinc is involved in over 300 enzymatic reactions—more than any other trace element except magnesium. Without zinc, the body cannot properly produce proteins, repair DNA, or even taste.
Signs of zinc deficiency
Zinc deficiency is more common than most people realize. According to the World Health Organization (WHO), up to 30% of the world’s population is zinc deficient. The risk group for deficiency includes athletes (zinc is lost through sweat), vegetarians and vegans (vegetable zinc is less well absorbed), the elderly and pregnant women. Symptoms to look out for:
- Common diseases — if you are constantly sick with colds or runny noses, the cause may be a weakened immune system due to a zinc deficiency
- Hair loss — zinc is necessary for the normal functioning of hair follicles. A deficiency causes hair thinning and slower growth
- Skin problems — acne, eczema-like rashes, dry and flaky skin, slow-healing wounds
- Nail changes — white spots on the nails, brittle and easily broken nails
- Loss of taste and smell — food seems tasteless, smells are weaker
- Mood swings — irritability, decreased concentration, in some cases depressive symptoms
- Slow wound healing — scratches and cuts take longer than usual to heal
If you recognize several of the above symptoms, it is worth checking your zinc levels with a blood test (serum zinc). A normal serum zinc level is 70-120 μg/dL.
Zinc forms — which supplement to choose?
Zinc is available in several different chemical forms in supplements. The form directly affects how well zinc is absorbed and what its effects are. Here is an overview of the most common ones:
Zinc citrate
Zinc bound to citric acid. Good bioavailability (about 60-70% absorbed), affordable price and wide availability. The most popular general-purpose zinc supplement in Estonia. Well suited for daily consumption and immune support.
Zinc picolinate
Zinc bound to picolinic acid. One of the most bioavailable forms of zinc — studies show it is up to 20% better absorbed than citrate or glycinate. The best choice for those who want maximum absorption, especially for quick correction of a deficiency.
Zinc glycinate
Zinc is bound to the amino acid glycine. Very well tolerated in the gastrointestinal tract — does not cause nausea or stomach upset, which some other forms of zinc can cause. A good choice for people with sensitive stomachs and for long-term use.
Zinc monomethionine (OptiZinc®)
Zinc is bound to the amino acid L-methionine. Often used in ZMA complexes (zinc + magnesium + B6). Antioxidant effect, supports liver function. Common among athletes to support testosterone and sleep.
Zinc oxide
The cheapest form of zinc supplement, but also with the lowest bioavailability (only ~50% absorbed). Contains the highest percentage of elemental zinc, but its poor absorption makes it ineffective. Not recommended for purchase — citrate or picolinate are clearly better choices.
Form comparison table
| Form | Bioavailability | Best use | Gastrointestinal tolerance |
|---|---|---|---|
| Zinc citrate | Good (60-70%) | General, immunity | Good |
| Zinc picolinate | High (70%+) | Deficiency correction, maximum absorption | Good |
| Zinc glycinate | Good (60%+) | Sensitive stomach, long-term use | Very good |
| Zinc monomethionine | Good | ZMA, sports, testosterone | Good |
| Zinc oxide | Low (~50%) | Not recommended | May be disturbing |
Dosage — how much zinc do you need?
Recommended Daily Allowance (RDA)
- Men (19+ years) — 11 mg per day
- Women (19+ years) — 8 mg per day
- Pregnant women — 11 mg per day
- Nursing mothers — 12 mg per day
For athletes
Athletes have a higher zinc requirement because zinc is lost through sweat (up to 1 mg of zinc can be lost during one intense workout). Actively training athletes may need 15-30 mg of zinc per day, especially strength trainers and endurance athletes.
Overdose — what to avoid
The upper limit of zinc intake is 40 mg per day (European Food Safety Authority, EFSA). In long-term overdose, zinc may interfere with copper absorption, which in turn leads to copper deficiency. Symptoms of excess zinc:
- Nausea and vomiting (especially on an empty stomach)
- Abdominal pain and diarrhea
- Metallic taste in the mouth
- Long-term overdose: copper deficiency, anemia, weakened immune system (paradoxically!)
Advice: if you consume more than 25 mg of zinc per day for a long time, also add a supplement 1-2 mg of copperto maintain balance.
Zinc and the immune system
Zinc’s effect on the immune system is one of the most studied functions of zinc. Zinc is necessary for both innate and adaptive immunity:
- T-cell development — Zinc is essential for the maturation of T-lymphocytes (virus-fighting cells) in the thymus gland. Without zinc, the number and function of T-cells are significantly reduced
- Anti-inflammatory effect — zinc helps regulate inflammatory responses, reducing the risk of chronic inflammation
- Antioxidant protection — zinc is a component of the superoxide dismutase (SOD) enzyme, which protects cells from oxidative stress
- Reducing the duration of a cold — several meta-analyses have shown that zinc intake at the onset of a cold can shorten the duration of the illness by 1-3 days
Studies show that even a mild zinc deficiency significantly reduces the responsiveness of the immune system. Adequate zinc intake is especially important during the autumn-winter period, when viral diseases spread more actively.
Zinc and testosterone — for men
Zinc plays an important role in regulating male hormones. Studies confirm that zinc deficiency has a direct negative impact on testosterone levels:
- A 1996 Wayne State University study found that healthy men who followed a zinc-deficient diet for 20 weeks had an average drop in testosterone levels 75%
- The same study showed that elderly men who received zinc supplementation for 6 months had testosterone levels doubled
- Zinc inhibits the aromatase enzyme, which converts testosterone to estrogen — so zinc helps keep testosterone levels higher.
This doesn’t mean that zinc is a miracle drug that will raise testosterone levels to the ceiling. The effects of zinc are most noticeable in cases of deficiency — if your zinc levels are already normal, supplementing with zinc will not significantly increase testosterone. However, it is important to ensure that you do not develop a deficiency, especially in men who are actively training.
ZMA (zinc + magnesium + vitamin B6) is a popular supplement for athletes, taken before bed. This combination supports testosterone levels, sleep quality, and muscle recovery. It is especially beneficial for men who exercise intensely and lose both zinc and magnesium through sweat.
Best Zinc Products
In omegafit.ee selection you will find various zinc supplements for every need — from simple zinc citrate to picolinate and combined preparations. Here are our recommendations:
The most affordable zinc products
Premium and specialty products
Frequently asked questions
When is the best time to consume zinc?
With food — Zinc on an empty stomach can cause nausea. It is best to take it with breakfast or lunch. Do not take zinc at the same time as calcium, iron or magnesium — these minerals compete for absorption. Leave at least 2 hours between doses.
Can you overdose on zinc?
Yes. Long-term use of more than 40 mg per day can lead to copper deficiency, which can lead to anemia and a weakened immune system. Up to 25 mg per day is safe for most people in the long term. If you are taking higher doses (30-50 mg), also supplement with 1-2 mg of copper.
Which form of zinc should I choose as a beginner?
Start with zinc citrate — it is the most versatile, well-absorbed, and affordable. If you want maximum absorption, choose zinc picolinate. For people with sensitive stomachs, zinc glycinate is best.
Does zinc help with acne?
Yes, several studies have shown that consuming zinc (especially in the form of zinc citrate and zinc glycinate) can reduce the severity of acne. Zinc regulates sebum production, reduces inflammation, and supports skin healing. To see results, you need at least 8-12 weeks consistent consumption.
Does zinc help with colds?
Yes. Meta-analyses show that zinc intake within the first 24 hours after symptoms appear, the duration of a cold can be shortened by 1-3 days. Zinc lozenges are usually used for this (15-25 mg every 2-3 hours while awake). For prevention, the usual daily dose (15 mg) is sufficient.
Where to buy zinc supplements in Estonia?
You can find a wide selection of zinc supplements in omegafit.ee e-shop. — from zinc citrate and picolinate to combined preparations (zinc + selenium, zinc + vitamin C, ZMA). Delivery throughout Estonia with Omniva and Itella parcel machines, usually within 1-2 working days.
You can also try the products on site and buy them from our store. OG Gym in Pärnu (Green 74).
If you have any questions, call +372 5562 2534 or write info@omegafit.ee — we’ll help you find the right zinc supplement for you!
Summary — which zinc to choose?
- Best price: ICONFIT Zinc & Selenium (4.90€) — zinc + selenium, 90-day supply
- Best absorption: Osavi Zinc Picolinate 50mg (12.90€) — zinc picolinate, highest bioavailability
- Best overall choice: OstroVit Pharma Organic Zinc (7.90€) — organic citrate, Pharma series
- Large package: Zinc 15mg 180 tablets (7.90€) — half a year’s supply
- With vitamin C: Vitamin C + Zinc Gummy Bear (12.90€) — tasty, suitable for children
Read other guides as well
- Magnesium Guide — Magnesium and zinc are the two most important minerals
- Vitamin C Guide — Zinc and vitamin C together strengthen immune defenses
- Vitamin D Guide — Vitamin D, zinc, and vitamin C are the immune trinity
- Collagen Guide — Zinc supports skin health and collagen synthesis