What you need to know about zinc

Dr. Jennifer Luis, B.Sc., B.Ed., N.D.

Dr. Jennifer Luis, B.Sc., B.Ed., N.D.

The mineral zinc is an important part of human nutrition and chances are you know someone who is currently supplementing with it. Zinc is required for vision, cell growth, reproductive health such as synthesis of testosterone, insulin balance, immune and skin health to name a few. Severe zinc deficiencies can cause delayed growth in children, a loss or decrease of smell or taste, swollen tongue, eczema and even hair loss.
Clinical signs of zinc deficiency is observed with of nail imperfections – white spots, hang nails, inflammation around the nail bed and vertical ridges or lines that can create a bumpy surface.

In practice, zinc supplementation is used to treat many different conditions. A short list includes:

  • auto-immune diseases (rheumatoid arthritis, Hashimoto’s etc)
  • acne, eczema, skin damage and post-surgery scar tissue
  • poor immune health
  • reproductive health – prostate conditions, infertility
  • eye health (cataracts, macular degeneration)
  • lack of taste or smell

The recommended daily allowance is 15mg per day, but typical supplementation is between 30 – 50mg per day. Long term (3 months or more) consumption of 30mg or more requires a small amount of copper to also be consumed. Minerals often compete for absorption, thus copper can become too low. A typical ratio of Zinc:Copper is 15mg:2mg or 30mg:2mg. Good quality supplements will often have a combination product to ensure balance. Of note, zinc doses above 20mg can sometimes cause nausea so taking with a big meal or just before bed can help.

There are many excellent food sources of zinc that can be enjoyed. The highest source is Eastern Oysters with around 100mg per 1/2 cup serving! If you aren’t an oyster lover, other foods include turkey (dark meat), Swiss chard, oats, pumpkin seeds, Swiss cheese and beef. It is important to note that supplemental doses of iron and calcium will lower the amount of zinc absorbed, so try to ensure taking these supplements at different times. If supplementing with high amounts of iron to correct anemia, it may also be recommended to take zinc to prevent deficiency. Some iron supplements will contain small amounts of zinc for balance.

Zinc is stored in muscles, the spleen, bone marrow and the liver. Since high concentrations of zinc are found in red blood cells (RBC) and white blood cells, testing for zinc is best done by looking at the RBC zinc levels and not just serum or urine testing. Companies such as Doctor’s Data provide accurate mineral levels with the RBC mineral analysis panel which is offered at Vitalia.