Fast vanishing zinc a superstar mineral we all need
Ahundred years ago, zinc was abundant in many soils. Nowadays, most soils in the world are zinc deficient, except for soils predominantly from biodynamic farms. This means that, where once fruit and vegetables, and even grain-based foods such as breads and cereals, provided us with a small, steady top-up of zinc, the zinc levels in many of the foods we eat today are inadequate to avoid deficiency.
Zinc is a superstar of a nutrient. It contributes to hundreds of processes inside your body, plenty of which are reflected on the outside. Zinc is critical for wound healing. Whether a cut on your finger, the place where a surgical incision was made, or the aftermath of a pimple, zinc is necessary for the skin involved in these traumas to heal and it helps to prevent scar formation.
Zinc is also required for proper immune system function, as well as for the maintenance of vision, taste and smell. It is essential to the creation of over 300 enzymes necessary for you to have great digestion: the foundation of all health. Zinc even nourishes the scalp, helping to maintain the integrity and strength of hair, and low zinc levels have been linked with hair loss and a dry, flaky scalp.
If you have a teenager at home with smelly feet that don’t seem to get any better no matter how many times they wash them, it’s likely to because of a zinc deficiency. Zinc is used in the production of sex hormones, and so when sex hormone production soars in teenage years, their requirements for this mineral skyrockets.
A zinc deficiency may be the underlying cause of sex hormone imbalances in adults, contributing to lowered testosterone, PMS, fertility challenges or monthly breakouts.
The recommended dietary intake (RDI) for a nutrient is the amount required to prevent a deficiency, not the amount needed for optimal health and great energy and vitality.
The RDIs for zinc across each age group are:
❚ 1-3 years: 3mg
❚ 4-8 years: 4mg
❚ 9-13 years: 6mg
❚ Boys: 14-18 years: 13mg
❚ Girls: 14-18 years: 7mg
❚ Men 19+ years: 14mg
❚ Women 19+ years: 8mg
❚ Pregnant women: 10-11mg
❚ Lactating women: 11-12mg
These days, our only real food sources of zinc include:
Food sources (per 100g)
❚ Oysters: 48mg
❚ Beef: 7mg (when cooked)
❚ Lamb: 3mg (when cooked)
❚ Eggs: 1.2mg (1 egg = 0.5mg)
❚ Seeds: 7mg (2mg per 30g serve) From looking at those food sources you can see that, realistically, we would probably need to be eating oysters every day to obtain enough zinc to avoid deficiency. But who eats oysters that often? So, if we look at beef, the next on the list: for a woman to meet her minimum requirements, she would need to eat at least 800g of cooked beef a week. Men would need almost 1.5kg of cooked beef per week to meet their minimum needs.
Yet, not only is this not practical but it isn’t even advisable. Why? Well, the World Cancer Research Fund (WCRF), one of the most evidence-based cancer research groups in the world, says to decrease the risk of colorectal cancer, we need to eat less than 500g of red meat per week.
So how on earth are we supposed to get our zinc these days? The answer is that most of us aren’t. Many people today are not getting enough of this vital mineral that is responsible for the taste and texture of food. It may be contributing to why young children today tend to be fussier with food than in the past.
Some signs of zinc deficiency may include:
❚ Poor blood glucose management; sugar cravings; loss of appetite; poor resistance to infection; skin infections; easy skin scarring; lowered fertility; and white spots on finger nails.
Zinc can be supplemented and, if it is, it is best taken before bed to maximise absorption.
❚ Dr Libby is a nutritional biochemist, best-selling author and speaker. The advice contained in this column is not intended to be a substitute for direct, personalised advice from a health professional. Join Dr Libby in Christchurch for one weekend to change your life: November 25 & 26. More info at drlibby.com.