Finally! Here I am, ready with the long-awaited part two of my post on dietary restrictions in pregnancy. As discussed last time, it can be frustrating to face so many “don’ts” when pregnant, especially when that list doesn’t give any actual indication of what the rationales behind those warnings are. In this series, I’m exploring different foods and beverages that are typically not recommended for pregnant women including the reasons they are considered unsafe or unwise to consume. Part one was concerned with contamination and the increased risks associated with food poisoning in pregnancy. Today, in part two, I’ll be talking about food and drink items that are associated with developmental problems in babies.
What do we mean by the term ‘developmental risk’?
When we talk about risks for babies in terms of development, we are often talking about brain development, but also development of organs, systems (such as the central nervous system or the respiratory system) and the skeleton. The jury is still out on what causes certain developmental problems in babies – such as autism – and others, such as Down’s Syndrome, have more to do with genetics and the age of the parents (typically, the focus has been on maternal age, but recent work has shown that paternal age may play a role too). There are some things found in certain foods, however, that can impact the healthy development of a foetus. This can go in both directions – that is, there are some things that babies need to get from their mothers (and that many people are deficient in) in order to develop properly and there are others that can interrupt or otherwise interfere with development and that should be avoided. Folic acid is a commonly referenced item in the first category, especially because it is so important in the first weeks after conception. If a pregnant woman is deficient in folic acid, her baby has a higher risk of spina bifida, a condition where the spine is improperly formed, leaving the spinal cord and meninges exposed in some areas. This is why all women of childbearing age are encouraged to take a multivitamin that contains folic acid and why all pregnant women should be taking a prenatal vitamin with folic acid as well. Iron, calcium, magnesium and other minerals, vitamins and nutrients are also important. In general, good nutrition supports the healthy development of a foetus, so making sure that you’re eating a balanced diet and taking your prenatal multivitamin is a great start.
What foods can negatively impact foetal development?
- Alcohol. Topping the list is probably the most often cited “don’t” for pregnant women. Drinking alcohol during pregnancy can lead to foetal alcohol problems (FAP) or fetal alcohol syndrome (FAS). Symptoms of exposure to too much alcohol in pregnancy can lead to neurological problems that lead to cognitive difficulties, facial formation problems, attachment problems, emotional disorders such as anxiety and depression in teens, developmental delays (e.g. learning to speak later than is considered ‘normal’), inappropriate sexual behaviour in teens or problems coping with one’s environment (e.g. extreme irritability, low tolerance for frustration, etc.). While small amounts of alcohol are probably ok for most people, no one really knows how much is too much and how that might vary from woman to woman and baby to baby. Because of those unknowns, it is generally recommended that women consume no alcohol during pregnancy.
- Mercury. Mercury is found in certain kinds of fish and shellfish, especially larger fish like marlin, king mackerel, swordfish and tilefish. Other fish that also contain more mercury than may be healthy include tuna and Chilean sea bass. Most fish contain either low or very low levels of mercury, but there are comprehensive lists online. The effects of mercury consumption on an unborn baby can include severe neurological problems and nervous system defects. While the instinct may be to just avoid fish altogether, this is not a good plan, because fish is one of the healthiest foods you can eat, both for you and your baby. Fish oils contain important Omega-3 fatty acids, as well as other nutrients, that are essential for your baby’s brain development. In addition to eating fish at least once a week, you may want to take a fish oil supplement daily for this reason. The trick is to completely avoid fish that have high levels of mercury, only eat those with moderate levels only a few times a month at most and stick to fish with the lowest levels of mercury for your regular intake (twice a week is ideal, but there is no need to restrict it to that if you like fish and want to eat more of the lowest-mercury varieties). The American Pregnancy Association has a great online resource that lists the fish within each of those categories. Mercury is not healthy for anyone, so it’s always wise to limit intake of those fish that contain high levels of mercury, but foetuses are definitely the most susceptible to mercury’s effects. Signs that a child has been exposed to too much mercury during gestation can include memory and attention problems; language difficulties; problems with cognitive thinking, fine motor skills or visual spatial skills; impairment of hearing, speech, walking or movement and other more subtle symptoms like pins and needles in hands and feet.
- Caffeine. This is a tricky one. Many women decide not to give up caffeine during pregnancy and most medical professionals say that small amounts of caffeine are ok. You should cut down on caffeine though if you normally drink a lot of coffee or tea as it can have potential impacts on development, as well as increasing the risk of miscarriage. Generally speaking, a moderate amount of caffeine is considered to be 150mg – 300mg per day. To be on the safe side, keeping your intake below 150mg (and talking to your healthcare provider about your intake, in case your specific situation is different) is the wisest course of action if you don’t want to cut it out altogether. A 6 oz cup of black tea (that’s pretty small, so make sure you know how much your mug holds!) contains about 45mg of caffeine and a 16oz cup of coffee (e.g.a Grande from Starbucks) contains about 400mg of caffeine. Pop, chocolate, green tea and some headache medications (e.g. Excedrin) also contain caffeine. Part of the problem with caffeine is that it affects the absorption of certain nutrients, like iron and calcium, which are essential to your baby’s development. So, if you’re taking an iron supplement or a calcium supplement, but drinking a pot of coffee every day, you are probably not doing your baby any favours. You can ask to have your iron and calcium levels tested if you’re worried about how much you’re absorbing (most pregnant women are tested for iron sufficiency routinely). Avoiding caffeine at the time of day when you take your supplements may help too, even if you’re only consuming small amounts of caffeine. In addition to the developmental problems that may stem from caffeine consumption, it can also increase your baby’s heart rate and affect his or her sleep patterns in utero and has been associated with low birth weights.
- Vitamin A. While we all need a certain amount of vitamin A, large quantities of vitamin A can lead to birth defects.Vitamin A is found in high quantities in beef and chicken liver, so you might be best to avoid those foods during pregnancy. You should also check to make sure that any supplements you may be taking do not contain vitamin A. Excess vitamin A consumption is associated with birth defects like heart defects and neural tube defects. These kinds of anomalies can cause lifelong disability or death. Vitamin A from beta-carotene (such as that found in mangoes, carrots, apricots, peppers, etc.) has not been associated with these same problems. However, if you are concerned about how much vitamin A you may be getting from orange fruits and veggies, talk to your healthcare provider about it.
- Unhealthy fats and sugars. While diabetes in itself is not a developmental disability, I felt that this last item fit best into this category, since diabetes in mothers can cause developmental problems in babies. Consuming a lot of junk food during pregnancy can contribute to your risk of developing gestational diabetes – that is, diabetes that occurs during pregnancy and goes away after the baby is born – which can have significant consequences for both your and your baby’s health. Eating a diet high in unhealthy fats and sugars also been strongly associated with diabetes in children, whether or not the mother develops gestational diabetes. While most people get the odd craving for potato chips, pop and other unhealthy foods, it is important to try to restrict these types of things during pregnancy. If you are at risk of developing gestational diabetes, you should take extra precautions to avoid sweets. Obviously, if you have diabetes pre-conception, you should be working with your healthcare providers to ensure that your blood sugar levels are being managed properly during pregnancy.
Just as it can be hard to change habits when it comes to food safety and contamination risks, it can be just as hard (maybe even harder) to change habits related to sugar and caffeine consumption. All you can do is your best! Be sure to eat lots of healthy foods and have compassion for yourself when you indulge the occasional craving.