Ask the health expert: Which foods are safe (and unsafe) to consume during pregnancy?

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Q: Which foods are safe (and unsafe) to consume during pregnancy?

A: Good nutrition is important during pregnancy because it safeguards the expectant mum's health and promotes good fetal development.

Protein is essential in the repair of the body's tissues and in the formation of the foetus' organs.

Good sources of protein include lean meat, poultry, fish, seafood, egg, dairy, and soya bean products. 

When consuming these foods, it is important to ensure they are thoroughly cooked. Raw foods (sashimi), undercooked meat and eggs, or soft cheese (brie, camembert and feta) may be contaminated with a bacteria called Listeria. It can cause food poisoning and also lead to miscarriages and stillbirths.

Studies have shown that pregnant women who eat oily fish such as salmon and sardine, have babies with higher IQ and better vision. The omega-3 fatty acids found in these fish have been found to aid in the development of the baby's brain and eyes.

However, expectant mums should avoid consuming fish such as shark, swordfish, king mackerel, tilefish, and albacore tuna, as they contain high levels of methyl mercury which is toxic to the foetus's brain and nervous system.

Hawker food to absolutely avoid when you are pregnant

  • Kopitiam breakfast set

    Coffee and soft-boiled eggs are a quintessential Singaporean way to start the day. But if you are pregnant, skip them.

  • "Too much caffeine during pregnancy can cause your baby to have a low birth weight and birth defects," says Nehal Kamdar, senior dietitian at KK Women's and Children's Hospital (KKH). In the worst-case scenario, you may even suffer a miscarriage.
  • Tip: Stick to two cups of weak tea or coffee and go for protein-rich hard-boiled eggs instead, advises Nehal.
  • Food poisoning can be fatal. In one of the worst cases in Singapore, two people died and a woman suffered a miscarriage after eating contaminated rojak from a popular Geylang Serai stall in 2009.
  • KH dietitian Jenette Yee says the dish is prepared using mainly uncooked food - a perfect breeding ground for bacteria such as listeria.

    In pregnant women, listeria infection can result in miscarriages, premature or still birth. Raw food may also carry E coli and intestinal worms.

  • Tip: Don't chance it! When dining at the hawker centre, avoid all uncooked food. If you love raw salad, eat it at home - after you've washed the veggies and fruit well.
  • Seafood like oysters, crabs and lobsters are particularly susceptible to heavy metal residue (lead and mercury).
  • These are toxic to your unborn baby, says nutritionist Mayura Mohta, founder of Healthfriend, which conducts nutrition workshops.

    "Too much mercury can damage a baby's developing nervous system," shares Agnes Wong, dietitian at the National Healthcare Group (NHG) Polyclinics.

  • Raw shellfish may also contain bacteria that can cause food-borne illnesses.

    "These could lead to minor symptoms like a mild bout of the flu, but it could also be severe enough to cause miscarriages," she adds.

  • Tip: A safer alternative is shrimp omelette, says Agnes. Shrimp is a good source of lean protein, zinc, iron, selenium and vitamun B12 - nutrients you need for a healthy pregnancy.

    Plus, this dish usually also contains mushrooms, onions and carrots, which provide fibre and other nutrients. Just make sure it's fully cooked.

  • Go easy on this oil-laden dish made of flour, ghee (fat) and cooked with even more oil.
  • "Most women need only 300 extra calories during pregnancy," says Lim Siew Choo, senior dietician at KKH.

    She explains that two pieces of plain roti prata with curry gravy can easily total 500 calories.

  • "Other than fat and carbohydrate, this dish does not contain significant amounts of nutrients like protein, iron, calcium and folate, which are important in pregnancy," she said.

    A nutritious breakfast should consist of slowly digested carbs (fresh food, wholegrain cereal) paired with protein (egg, reduced fat cheese, soya bean milk), advises Siew Choo

  • Tip: A healthier choice would be thosai or idli with dal curry, which contains just 305 and 269 calories respectively.

    "Dal curry also provides protein and fibre, with very little added fat," she added.

  • Japanese-style teriyaki fish set

    This much-loved meal - served with either rice or noodles - consists of deep-sea fatty fish like salmon or sardines.

  • These are rich sources of omega-3 fatty acids, which help in baby's brain and eye development, says Jenette.

    Tip: Worried about toxic metals in seafood? According to Agnes, pregnany women can safely eat up to about 360g of cooked seafood such as shrimp, canned light tuna, salmon, crab and catfish per week.

  • She recommends rationing albacore ("white") tuna to 170g or less per week, as this variety contains more mercury that canned light tuna.

    "Alternatively, you can also get your omega-3 fatty acids from soya beans and eggs fortified with omega-3 fatty acids," she said.

  • According to the experts, this is one of the healthier hawker choices.
  • "Fish is an excellent sources of high-quality protein, as well as other nutrients like vitamin D and iodine," says Jenette.

    However, the US FDA recommends that pregnant women avoid large fish like shark, swordfish and ikan batang.

  • But don't most hawkers use ikan batang for sliced fish soup? "According to the Agri-food and Veterinary Authority of Singapore, the mercury level of fish imported into Singapore is monitored, so the ikan batang used shouldn't contain high levels," shared Jenette.
  • However, she recommends limiting this food choice to twice a week.

    Tip: Don't just drink the soup, says Jenette. "Be sure to eat the fish too!" The nutrients are in both the soup and ingredients.

  • Served with meat, egg, veggies and ikan bilis, this soupy noodle dish is one of the more balanced street food options for expectant mums.
  • "Compared to other hawker food, ban mian is lower in fat, high in protein and comes with fibre from vegetables," says Agnes.
  • To be safe, make sure the egg is thoroughly cooked, she adds.

    In general, dishes that are cooked only after you place your order are a safer option when dining at hawker centres, adds Nehal.

  • Tip: Ask for extra helping of veggies. The additional fibre will ease constipation, a common and annoying pregnancy problem.
  • To achieve a balances meal with this dish that's usually eaten with rice or porridge, Nehal advises including a serving each of protein (lean meat, fish, chicken or beans) and vegetables.
  • Make sure to vary your choice of veggies every day, as different coloured ones give you different types of vitamins, minerals and antioxidants, says Nehal.
  • If the stall offers brown rice, opt for that. The wholegrain version gives you added fibre, which keeps you full longer and benefits your heart.

    To enhance iron absorption, end your meal with a slice of fruit, advises Nehal.

  • Satay

    This meaty dish may be high in protein, iron, niacin and vitamin B6, but be careful where you eat it.

  • Avoid roadside hawker stalls or warungs (when overseas). These places may have poor hygiene levels and the food is often cooked out in the open or exposed to dust and flies, says Agnes.

    Avoid eating the raw vegetables such as onions and cucumber that are typically served with satay.

  • To decide which stalls to purchase from, Agnes advises checking the standard of hygiene before ordering. And if you love your grilled meat, consider preparing your own grilled chicken (skinless) or other lean cuts at home.

    This way, you get to enjoy it and its higher nutritional values, and lower your risk of infection, says Agnes.

  • While this one-dish hawker fare is relatively low in calories (one bowl contains about 370), Siew Choo says it's generally low in fibre, protein (sorry the fish balls don't really count) , vitamins and minerals.
  • But you can certainly make it healthier by choosing the soupy version and getting the stall uncle to top up some ingredients.

    By choosing the soupy version, you would cut down on added salt and other preservatives from the chilli and tomato sauces.

  • Get the uncle to add extra lettuce and bean sprouts )and lean meat, if available).
  • Some stalls also include liver in the dish. Nehal advises going easy on this ingredient.

    "Limit intake to two tablespoons per week in the first trimester, as it's rich in vitamin A. Too much of this vitamin can cause birth defects in babies," she explained.

It is also best to avoid caffeine totally as it is a stimulant. Consuming excessive caffeine during pregnancy may add stress to the developing foetus by increasing its heart rate and metabolism, which in turn increases the risk of miscarriage.

Pregnant women can consider drinking decaffeinated coffee and tea which contain trace amounts of caffeine, or natural caffeine-free teas such as peppermint, chamomile, and certain types of floral tea.

In addition, alcohol should be avoided during pregnancy as it can pass from the blood through the placenta to the baby. This may lead to fetal alcohol syndrome which may result in poor growth, learning difficulties, and behavioural problems later in life.

However, a small amount of alcohol added during cooking is considered safe if the food is simmered for at least 30 minutes to allow the alcohol to vapourise.

Ms Ho Pey Ying, Dietitian, KK Women's and Children's Hospital

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