Zinc is a trace mineral that plays many vital roles in your body. Because your body doesn’t naturally produce zinc, you must obtain it through food or supplements. Zinc is a component of every living cell in the body and is essential for the structure and function of over 100 enzymes.
This Chinese-style surf and turf is a fantastic source of Zinc because of the combination of both beef and oysters. You can get the recipe here.
Why is zinc important?
Zinc is a component of every living cell in the body and is essential for the structure and function of over 100 enzymes. Zinc is important for:
Growth and development in children
Normal fertility and reproduction
Maintenance of normal testosterone levels in the blood
Night vision
Appetite
Protein synthesis
Sense of taste and smell
Maintaining a strong immune system and wound healing
Maintenance of hair and nails.
Zinc is widely distributed in foods, but the amount your body absorbs varies.
How much zinc do we need?
Our zinc requirements vary, depending on age and gender. The rate of zinc absorption also varies from about 15 to 40%, depending on a person’s zinc status – if more is needed, more is absorbed.
According to the last National Adult Nutrition Survey (2008/9), one in four New Zealanders, aged 15 years and over, had an inadequate intake of zinc (males 39.1%; females 11.2%).
It is estimated that 7.3% of New Zealand children have an inadequate intake of zinc. However, older children, aged 11-14 years have a higher prevalence of inadequate zinc intake than younger children, aged 7-10 years.
Recommended Dietary Intake / day of Zinc at different life stages
Sources of zinc
New Zealand beef and lamb have a high zinc content and are the most commonly eaten sources of zinc in New Zealand.
The type of protein in foods such as red meat promotes zinc absorption. This means zinc has a higher uptake by the body from meals containing meat. Plant foods such as grains and legumes often contain phytates and dietary fibre, which can reduce zinc absorption.
The foods highlighted in green indicate they are a good source of zinc, having over 25% of the daily zinc requirements based on an average adult diet of 8700 kJ.
Who needs more and why?
Teenagers need more zinc to help with their growth and development.
Pregnant and breastfeeding mothers need more zinc to support both themselves and the growing infant
People with gastrointestinal issues and other diseases, such as inflammatory bowel disease, coeliac disease, renal disease, all types of diabetes and cancer, this is to support and immune system and/or counteracts any malabsorption issues. Medical and dietary advice should be sought from a registered health professional.
Vegetarians and vegans. The absorption of zinc, is lower in vegetarian diets because vegetarians eat more legumes and wholegrains (these contain phytates, which reduce zinc absorption) while avoiding meat (which is a source of zinc). The requirement for dietary zinc may be as much as 50% greater for vegetarians, particularly strict vegetarians whose major staples are grains and legumes.
References:
Ministry of Health. 2003. NZ Food NZ Children: Key results of the 2002 National Children’s Nutrition Survey. Wellington: Ministry of Health.
National Institute of Health. Office of Dietary Supplements. Zinc fact sheet for health professionals. July 2019.
National Health and Medical Research Council (NHMRC), Nutrient Reference Values for Australia and New Zealand including recommended dietary intakes: April, 2014.
University of Otago and Ministry of Health. 2011. A Focus on Nutrition: Key findings of the 2008/09 New Zealand Adult Nutrition Survey. Wellington: Ministry of Health.
Whitney, E., Rolfes, S.R., Crowe, T., Cameron-Smith, D., Walsh, A. (2011). Understanding Nutrition: Australian and New Zealand Edition. 1st edition. Melbourne, Australia