Other healthy eating tips

Other healthy eating tips

Pregnancy is a time when nutritional requirements change to meet the needs of both mother and child. A full discussion on the nutritional needs of pregnant women is contained in the Ministry of Health’s Eating for Healthy Pregnant Women (code HE1805) and Your Pregnancy (code HE1420). See www.healthed.govt.nz (External)

The following are some of the key safety-related nutritional issues.

Folic acid

Folate is a B vitamin that is needed for the formation of blood cells and nerve tissue. It is found naturally in food, especially green vegetables and grains. Folic acid is the synthetic form of folate which may be added to manufactured foods or taken as a vitamin supplement.

Requirements for folate and folic acid increase during pregnancy and breastfeeding. Women who don’t get enough folate and folic acid before and during pregnancy have a higher risk of their baby developing abnormalities known as neural tube defects (NTDs). The neural tube is the nerve centre of the foetus and grows into the spinal cord. The most common NTDs are spina bifida and anencephaly.

Women capable of or planning a pregnancy should take at least 400 micrograms (mcg) of folic acid daily as well as consuming foods rich in folate and folic acid fortified foods. The Ministry of Health advises women to take a registered 800 mcg folic acid tablet daily for at least four weeks prior to conception and for the first 12 weeks of pregnancy. Currently a subsidised 800mcg folic acid tablet is available over the counter from pharmacies, or on prescription from your doctor or midwife. These are the only subsidised registered folic acid tablets available in New Zealand that are recommended by the ministry of Health.

Bread manufacturers have voluntarily started increasing the range of breads that have added folic acid. However, while the folic acid that is added to bread boosts the dietary intake of the nutrient, it is not enough to substitute the recommended folic acid tablet. This over-the-counter supplement should be taken four weeks prior to conception and for the first 12 weeks of pregnancy.


Folic acid fortified breads


Iodine occurs naturally in most foods, but usually in small amounts. Iodine is an essential nutrient for growth and development, including normal brain development. It is vital that unborn babies, infants and young children have enough iodine. Although iodine is essential, too much iodine can be harmful to health.

Requirements for iodine increase during pregnancy and breastfeeding. It is important at this time to take an iodine-only tablet on a daily basis and to choose foods that are not only rich in iodine, but are also safe for you and your baby.

Iodine-only tablet

You can get a subsidised iodine-only tablet (containing 150 micrograms of iodine) specifically made for pregnant and breastfeeding women from pharmacies or on prescription from your doctor or midwife. This tablet is manufactured in accordance with good manufacturing practice to ensure it contains the recommended amount of 150 micrograms of iodine.

Other iodine containing supplements, including seaweed and kelp supplements, are not recommended as the iodine content in some of these products is extremely variable and there are risks from having too much iodine.

If you have any concerns about your iodine intake, talk to your midwife or doctor about what is best for you and your baby.
The iodine-only tablet can provide about two-thirds of your recommended daily iodine needs during pregnancy and breastfeeding. The other third will need to come from food.

Foods containing iodine

From September 2009 most bread (except organic) must contain iodine. Iodine has been added to bread to increase the amount of iodine the general population, including pregnant and breastfeeding women, can obtain from food. However, this does not replace the need for pregnant and breastfeeding women to take an iodine-only tablet.

It is also recommended that you regularly choose foods that are good sources of iodine. These include:

  • most bread (except organic)
  • low-fat milk and milk products
  • eggs
  • cooked fish and some shellfish
  • home-made sushi (when prepared with freshly cooked rice, without raw, smoked or cold cooked meat or seafood and eaten immediately). 

For more information on the types and amounts of fish and shellfish you can safely consume during pregnancy, see MPI’s ‘Pullout guide to food safety in pregnancy’. Find the link in the panel to the right.

Products containing brown seaweed

Be careful when choosing foods containing brown seaweed. Brown seaweeds are typically sold dry and are used in soups and stewed dishes. Brown seaweeds, such as kelp, kombu, wakame, quandai-cai, hiziki/hijiki, arame or Sargassum fusiforme contain naturally high and varying levels of iodine. If brown seaweed is consumed regularly the high levels of iodine can be too high for pregnant and breast feeding women. It is recommended that you eat no more than one serving of brown seaweed a week.

Nori is a green seaweed which is also sold dried and used in many seaweed-containing products. Unlike brown seaweed, it contains safe levels of iodine, so is not restricted to one serving a week.

Use iodised salt

New Zealanders are generally recommended to reduce salt intakes, including salt from processed food and salt added at the table. However, if you do choose to use salt, choose iodised salt.

Iodine and fortification


Drinks containing caffeine, including coffee, teas and colas, should be limited during pregnancy. You may want to consider giving up caffeine altogether. Have no more than six cups of tea or instant coffee, or three espresso-style coffees daily. Energy drinks and ‘smart drinks’ are not recommended as they may contain high levels of caffeine and other ingredients not recommended for pregnant and breastfeeding women.

Herbal preparations and teas

Be cautious about drinking herbal preparations and teas during pregnancy. Discuss with your health professional what options are safe for you and your baby.


There is no known safe level of alcohol consumption for pregnant women. Alcohol crosses the placenta so whatever a mother consumes, the foetus will also receive. Excessive alcohol consumption is associated with Foetal Alcohol Syndrome (FAS) where the infant may have varying effects including intellectual impairment. Even at lower levels of alcohol consumption, infants may show behavioural and learning difficulties that have been linked to alcohol consumption.

It is therefore advisable to avoid alcohol during pregnancy or when contemplating pregnancy.

Mercury in fish

Eating fish during pregnancy is recommended as part of a well-balanced diet because it is a nutritious food for you and your growing baby. Fish is low in saturated fat and an excellent source of protein, essential omega-3 fatty acids, iodine and some vitamins. Omega-3 is important for the development of the central nervous system in babies, before and after they are born, and fish is a recommended food for all people.

For the many commonly eaten fish species in New Zealand there is little concern about mercury levels and these can be eaten freely. Mercury occurs naturally in the environment and accumulates in the aquatic food chain as methyl-mercury so all fish contain some methyl-mercury.

To ensure your exposure to mercury is within safe limits, it is recommended that women who are pregnant or considering pregnancy limit their consumption of fish containing higher levels of mercury and eat a variety of fish where possible. In the information below, a portion size when mentioned is about is 150g.

Fish that are likely to contain the lowest levels of mercury include: farmed salmon, skipjack tuna, tarakihi, blue cod, hoki, john dory, monkfish, warehou, whitebait, flat fish (eg flounder), as well as mussels and pacific oysters. Small, canned fish such as sardines and mixed fish (eg, battered fish and fish fingers) can also be eaten without restriction.

Species to be mindful of during pregnancy are some of the longer-lived and larger fish, and consumption of these should be limited to three to four portions per week. These include albacore tuna, blue mackerel, gemfish, orange roughy, ling, skate, kahawai, hapuka (groper), bluenose, ghost sharks, bass, oreo dories, red cod, ribaldo, rig (spotted dogfish or lemonfish) and rock lobster.

There are a small number of species where it would be wise to eat no more than one serving per week or fortnight during pregnancy, and not at all if consuming other species of fish. These include dogfish (apart from rig), school shark, swordfish, marlin, cardinal fish and fish such as trout caught in geothermal regions (mercury is in volcanic emissions).

Mercury in fish

Cadmium in shellfish

Bluff oysters and Queen scallops have high cadmium concentrations and it is recommended that you minimise your intake (regardless of how they are prepared) during pregnancy.