Zinc

What is zinc?

Zinc is a mineral that is essential for human health and is involved in numerous biological processes, including cell division, wound healing, and DNA synthesis and protein synthesis. It acts as a cofactor for many enzymes, helping to activate or deactivate certain chemical reactions. Zinc is also involved in the immune system, acting as an antioxidant and helping to fight off infections.

How does it work?

Zinc has multiple mechanisms of action in the body that support its medicinal properties. It functions as an antioxidant, helping to prevent oxidative damage to cells and tissues. It also helps support the immune system, as well as proper growth and development during pregnancy, childhood, and adolescence.

What are the active ingredients that are important for its medicinal properties?

The active ingredient in zinc supplements is zinc ions.

What forms does it come in?

• Oral tablets
• Capsules
• Lozenges
• Liquid solutions.

Different types of zinc:

• Zinc gluconate
• Zinc acetate
• Zinc sulfate
• Zinc metal
• Zinc oxide
• Zinc carbonate
• Zinc chloride
• Zinc picolinate
• Zinc citrate
• Zinc orotate
• Zinc chelate
• Zinc sulfide
• Zinc stearate
• Zinc hydroxide
• Zinc phenolsulfonate

What if there’s an imbalance or deficiency?

Zinc deficiency can cause a range of symptoms such as impaired immune function, slow wound healing, and decreased taste and smell sensitivity. In severe cases, zinc deficiency can cause growth retardation, loss of appetite, and impaired cognitive development.

When was it first used for medicinal purposes?

The medicinal properties of zinc have been recognized for centuries, with ancient civilizations using zinc-rich foods and minerals to treat a variety of ailments. Modern medicinal use of zinc began in the 20th century, with its role in supporting immune function and wound healing being the main focus of research. In recent years, zinc has been the subject of numerous clinical trials and studies, which have shown its effectiveness in treating a variety of conditions and symptoms.

Summary:

Zinc is an essential mineral that is important for numerous functions in the body, including immune function, wound healing, and DNA synthesis. Zinc deficiency can lead to a range of symptoms and is commonly found in oysters, beef, pork, chicken, beans, nuts, and dairy products. The recommended daily dose of zinc for adult men and women is 11 mg and 8 mg, respectively, and zinc supplements can be taken with or without food.

What does Zinc help with?

Zinc is a mineral your body needs in small amounts. You get it from meat, shellfish, beans, nuts and whole grains. It is sold as lozenges, tablets, capsules and skin creams.

The evidence for zinc is strong overall, but not for every use. Most of it comes from people who were low in zinc to start with. Each use below carries its own grade.

• Sudden diarrhea in young children
  Strong evidence — many randomised trials in children, behind a World Health Organization recommendation. The World Health Organization advises zinc for children with sudden diarrhea. The case is strongest in lower-income countries. In those trials, zinc shortened how long the diarrhea lasted and made it less severe. Low zinc is thought to weaken the gut lining, and zinc helped restore that barrier quickly.
  Evidence grade A · Traditional tier T0
• A cold you can feel coming on
  Good evidence — repeated randomised trials of lozenges started within 24 hours of the first symptoms. In trials, people who took zinc lozenges within 24 hours of the first symptoms had shorter, milder colds. Lab studies suggest zinc stops cold viruses from latching onto cells in the nose and throat. Lozenges started later have not been tested in the same way.
  Evidence grade B · Traditional tier T0
• Vision loss from age-related macular degeneration (AMD)
  Good evidence — the large AREDS randomised trial, in people who already had AMD. The landmark AREDS trial tested one set formula: high-dose zinc plus antioxidant vitamins. In people who already had AMD, that formula lowered the risk of moving on to advanced AMD. Zinc is found in high amounts in the retina.
  Evidence grade B · Traditional tier T0
• Mild to moderate acne and oily skin
  Good evidence — human trials in mild to moderate acne, smaller and fewer than drug trials. In trials, zinc reduced the red, swollen spots of mild to moderate acne. It appears to calm the inflammation that turns a clogged pore into a breakout, and to curb skin oil. Lab work shows mild action against the bacteria linked to acne.
  Evidence grade B · Traditional tier T0
• Wounds, ulcers and burns that are slow to heal
  Early evidence — studies in people who were already low in zinc. In people who were low in zinc, extra zinc sped up healing of surgical wounds, ulcers and burns. Zinc is well established in nutrition science as a building block for new skin cells and collagen. Wounds tend to heal slower when zinc is low.
  Evidence grade C · Traditional tier T0
• Low sperm count or poor sperm movement
  Early evidence — supplement studies, mostly in men with low zinc levels. Studies found that zinc raised sperm count and movement. The gain showed up mainly in men who were low in zinc. Zinc sits in high amounts in the testes and takes part in sperm development and DNA repair.
  Evidence grade C · Traditional tier T0
• Low testosterone in men
  Early evidence — studies in men who were low in zinc, not in men with normal levels. Men who are low in zinc often have clearly lower testosterone. In studies, fixing that shortfall moved testosterone back toward normal. The effect showed up most in men who sweat heavily or eat little red meat.
  Evidence grade C · Traditional tier T0
• Low mood and depression
  Early evidence — several small trials of zinc added to standard treatment. Several trials added zinc on top of usual depression treatment. Those trials found better depression scores than usual treatment alone. Low zinc levels also turn up more often in people with depression. Researchers think zinc acts on brain signals such as serotonin, but that idea rests on lab work.
  Evidence grade C · Traditional tier T0
• A dull sense of taste or smell
  Early evidence — small studies in people whose loss was linked to low zinc. Low zinc is a recognised cause of a faded sense of taste or smell. In small studies, zinc helped bring both senses back in people who were low. Nutrition and lab work show zinc helps keep taste and smell cells working.
  Evidence grade C · Traditional tier T0

What Zinc has not been shown to do

• Zinc has not been shown to raise testosterone in men whose zinc levels are already normal.
• Zinc has not been shown to strengthen immune defence in people who already get enough of it; the gains seen were from correcting a shortfall.
• Zinc has not been shown to stop a cold from starting; the lozenge trials began after symptoms had already appeared.
• Zinc has not been shown to speed wound healing in people with normal zinc levels.
• The AREDS trial studied people who already had AMD, so it does not show that zinc prevents AMD in healthy eyes.

How to read this:

A grade tells you how strong the human evidence is, not how strong the effect is. A means steady results across randomised trials in people. B means at least one good trial. C means small or mixed human studies. D means weak or conflicting human evidence. Insufficient means no human study on file. This page reports what studies found. It is not medical advice, and it is not a promise that zinc will work for you. Talk to a doctor or pharmacist before you start, especially if you take other medicines.

What can Zinc help prevent?

• Progression of age-related macular degeneration to advanced stages
• Duration and severity of the common cold when taken early
• Complications from zinc deficiency in pregnancy (preterm birth, low birth weight)
• Recurrent diarrhea episodes in malnourished children

Which foods are rich in it?

• Oysters
• Beef
• Pork
• Chicken
• Beans
• Nuts
• Dairy products
• Legumes
• Eggs
• Whole grains
• Seafood

What are possible side effects?

• Gastrointestinal symptoms
• Nausea
• Vomiting
• Stomach cramps

Overdose:

In some cases, high doses of zinc can interfere with the absorption of copper and iron, leading to anemia.

What’s the recommended daily dose?

Adult women: 8 mg

Adult men: 11 mg

How long does it take to work?

The time it takes for zinc to start working depends on the condition being treated and the individual's response. For some conditions, such as the common cold, improvement may be seen within a few days of starting zinc supplementation.

What time of day is best to take it?

It can be taken any time of day.

Should I take it with food?

It can be taken at any time with or without food, but best to take with food to improve absorbtion.