Michelle Coursey outlines some nutrients you need every day.
We may live in the land of plenty, but there are still some essential nutrients missing from many Kiwi diets. Here we take a closer look at three important elements your body needs for feeling and working better, the reasons you probably don't get enough nutrients; and how to get your levels at their best.
Iodine
What is it? Our bodies don't naturally make iodine, so we need to make sure we get enough from the foods we eat in order to support our thyroid, which helps growth and development. It is an essential element that New Zealand soils are low in, and in the New Zealand Food Safety Authority's 2003/04 survey, it was found that Kiwis may be eating up to 60 per cent less than the recommended daily dose of 150mcg per day.
Why do I need it? Without sufficient iodine, our cognitive function may be affected, and there is more chance of thyroid disease, and goitre (a swelling of the thyroid gland in the neck). It is particularly important for children to get enough (about 90mcg a day from the age of 1) for growth and good cognitive skills to be developed.
How do I get more of it? New Zealand's table salt has been fortified with iodine to keep levels up, but because of an increase in packaged foods without iodised salt - and much of the population reducing their salt intake for healthier living - iodine is not as common as it once was in a standard diet. Since 2009, it has been mandatory for all bread to be fortified with iodine, so sandwiches are a good option to top up your levels. Nutritionist Karen Dickinson, of Body Acoustics Health and Sports Nutrition, says including iodised salt in moderation at the table or in cooking will help.
"Food sources that include iodine are seaweed, seafood and fish, dairy products and eggs. Sushi is a great source of iodine," says Dickinson. "If you're choosing iodine or kelp supplements, do so under the supervision of your doctor."
Selenium
What is it? New Zealand is one of a group of countries that has very variable and low levels of selenium in its soils, which means many Kiwis don't get much of this essential trace element. The National Nutrition Survey in 1997 (the most recent record of the country's nutritional health) found men and women had low, but sufficient, levels of the element in their diet, but those levels are much less than many other Western countries' averages.
Why do I need it? "Selenium helps protect our bodies against damage by acting as an anti-oxidant, helping to regulate blood pressure and keeping our immune system healthy," Dickinson explains. The recommended dietary intake of selenium is 60mcga day for men, and 70mcg a day for women.
How do I get more of it? Foods that are high in selenium include almonds, which make a great snack. Dickinson recommends having a poached egg or natural muesli for breakfast, and a Hoki fillet, tuna, chicken breast or fillet steak with pasta for dinner to maximise the amount of selenium in your diet. Another easy way to increase levels is to simply eat one Brazil nut a day. Researchers at the University of Otago have shown they are very high in the nutrient, although Dickinson warns not to eat more than two or three per day as it is possible to get sick from too much selenium.
Iron
What is it? Iron is a mineral that has three main purposes - to carry oxygen around your body, to help your immune system stay at full strength as the cells that fight infections need enough iron to function, and to help chemical reactions that provide your body with energy. It's thought that one in four New Zealand women don't get enough iron in their diet.
Why do I need it? Without enough iron, all of the bodily functions mentioned above will suffer - you'll feel less energetic, your immune system will be weakened, and you may develop iron-deficiency anaemia. The recommended amount of iron for men and women aged 19-50 years old is 18mg a day. Pregnant women need much more - 27mg a day.
How do I get more of it? The best way to load up on iron is to eat red meat - although there are many other sources available. Mussels and oysters are high in iron, as are liver and kidney, as well as whole grains, beans, peas, cashew nuts, sunflower seeds, dried fruit, and green leafy vegetables including broccoli, silver beet, and Chinese cabbage.
Dickinson suggests including foods high in vitamin C - such as oranges, grapefruit, tomatoes, broccoli and strawberries - with your meal to help boost iron absorption.
"Try having fresh orange juice alongside a red meat meal, or broccoli, peppers and cabbage in a chicken stir-fry."