Our nutritional needs change throughout our lifetime – what a newborn baby needs is vastly different from the requirements of a teenager and the same is true for women during the phases of pre-conception, pregnancy and post-childbirth. Nutritional needs depend on our age and stage of development – and missing out on these can have implications for children and adults. Amanda Tomlinson examines the needs of each stage.
Pre-conception
Good health starts before conception, with the mother-to-be ensuring she has enough of the right nutrients in her diet. In this phase, one of the most important micronutrients is folate – a deficiency of which can result in neural-tube defects, such as spina bifida, in the baby. Women trying to conceive should start taking folic acid supplements – 400 micrograms daily is recommended – for at least one month before conception. Food sources of folate are beans, spinach, broccoli, asparagus and fortified grains such as cereal and breads.
Women should also ensure their weight is within the healthy range as those who are over or under weight may have a harder time becoming pregnant. Eat a healthy diet, avoiding refined, processed foods and foods with added sugars, such as flavoured yogurts and sodas.
Clinical dietitian Stephanie Tait, who works with Bespoke Wellness, says women can get their daily nutrient needs by eating 170 grams of grains (a cup of quinoa), two cups of fruit, two-and-a-half cups of vegetables, 156g of protein (one palm-sized chicken breast and a handful of nuts) and three cups of dairy (milk, cheese or yogurt).
Pregnancy
While energy needs increase during pregnancy, there is no need to “eat for two”. What’s most important is the nutritional quality of the food consumed. Tait says women need at least 27 milligrams of iron a day, which can be obtained through meat, chicken and beans, and at least 1,000mg of calcium, through milk, yogurt, hard cheese and salmon. Pregnant women need to be especially careful of food-borne illnesses such as listeria, and are advised to avoid undercooked and raw foods such as sushi, unwashed fruit and vegetables, soft cheeses and soft-serve ice cream. Tait says women should also avoid swordfish, tilefish and king mackerel because of the high mercury levels.
The New Zealand Ministry of Health suggests at least six servings a day of vegetables and fruit (more vegetables than fruit), at least six servings of breads and cereals (wholegrain rather than processed), at least three servings of milk and milk products, at least two servings of protein (lean meats, chicken, eggs, beans, lentils, nuts and seeds) and at least nine cups of fluid.
Breastfeeding mothers
At this stage there is less need for iron and folate, but an increased need for energy, vitamins A, C and E, riboflavin, iodine, selenium and zinc. Tait recommends women take a multivitamin supplement to boost nutrient intake and, because of the increased energy requirements, that they eat five to six small meals and snacks a day. She suggests drinking two to three litres of water a day and consuming 200g of grains, two cups of fruit, three cups of vegetables, 170g of protein and three cups of dairy.
Birth to 12 months
Breast milk is a complete nutritional source for babies and it is recommended that they are fed on it exclusively for at least the first six months. Babies who are breastfed have fewer infections, allergies and intolerances. “Do not feed babies solid foods before five or six months. They are not developmentally ready for food before this time. In addition, introducing food early increases the chance for food allergies and choking,” says Tait.
Baby foods can be introduced at six months but “it’s very important to introduce baby foods one at a time, so that you can notice if the baby has a reaction to a certain food,” says Tait. “It’s important to introduce vegetables before fruits, so the baby doesn’t develop a sweet tooth. Also, avoid hard foods due to the baby not having many teeth and due to the choking risk. Everything should be soft, puréed or mashed.” She suggests foods be introduced in the following order: cereals, vegetables, fruits, then meat, while continuing breast milk or formula.
Preschool
During the preschool years, iron deficiency anaemia is common and can lead to decreases in stamina and learning ability. Parents should ensure their children get at least seven milligrams of iron each day through sources such as cereals, meat, chicken and greens. Tait says parents should not give their children juice, even 100 per cent juice, because of the sugar content. “It adds not only extra calories, but can lead to tooth decay and cavities. Choose water instead and if you do give children juice, dilute it with at least half water.” Preschoolers should get at least 110g of grains, one cup of fruit, one-and-a-half cups of vegetables, 85g of protein and two-and-a-half cups of dairy a day.
At this age, children are prone to constipation, so include plenty of fluids and fibre-rich foods such as wholegrain breads and cereals, beans and vegetables. Children between the ages of 1 and 3 years should have 14g of fibre a day, while children between the ages of 4 and 8 should consume 18g a day.
School age
Calcium, vitamin A and vitamin C are essential nutrients for this age group, says Tait. She recommends 1,000mg of calcium a day for strong bones and teeth, 400 to 600 micrograms of vitamin A for bone, teeth and eye health as well as proper immune function, and 25 to 45mg of vitamin C a day for development, healing wounds and immune strength. Good sources of calcium are milk, yogurt, cheese, salmon and greens. Vitamin A can be found in orange fruits and vegetables, such as carrots, mangoes and sweet potatoes, as well as in spinach, broccoli and milk, while citrus fruits, strawberries, bell peppers, tomatoes, broccoli and papaya are good sources of vitamin C.
Overweight and obesity are becoming increasingly common in this age group and can lead to health conditions such as type 2 diabetes and cardiovascular disease. A healthy diet and regular physical activity can help children stay within the recommended weight-for-height ratios. Tait says a healthy diet for school-age children includes 170g of grains, one-and-a-half cups of fruit, two-and-a-half cups of vegetables, 140g of protein and two-an-a-half cups of dairy.
Teenage
Girls tend to have a growth spurt between ages 10 and 13, gaining about 25 centimetres, while boys usually experience it between ages 12 and 15 and grow about 30cm. The growth spurt leads to increased hunger, however if the child is not eating nutritious food, it can result in excess weight. “Many teens are now obese, therefore they should limit excess carbohydrates from bread, rice, pasta, processed and refined foods, and also sugary beverages such as sodas and juices,” says Tait.
She says teens also tend to fall short on calcium, iron and zinc. “Calcium needs increase to 1,300mg a day due to increased growth and bone mineralisation. Sources include milk, yogurt, cheese and salmon. They also need 8 to 15mg of iron a day for growth and to prevent anaemia, which can be obtained through cereal, meat, chicken and greens.” And by eating seafood, meat, beans and seeds, teens can get the required 8 to 11mg of zinc each day for adequate growth.
Teenagers should consume 200g of grains, two cups of fruit, three cups of vegetables, 170g of protein and three cups of dairy.
