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Prenatal Vitamins: Is Diet Enough? When and What to Supplement
June 16, 2017
I’ve talked about the best vitamins for women to take in general, but  what about the prenatal vitamins a woman needs when she’s pregnant? When you compare a woman’s multivitamin to a woman’s prenatal vitamin, the prenatal vitamin typically contains more folate and iron. A woman’s increased nutritional needs during pregnancy are the result of two things: the physiologic changes of the mother and the metabolic demands of the fetus.
A nutrition-rich pregnancy diet is not just vital to the mother’s health — it’s also essential to the healthy development of her offspring now and into adulthood. Specific nutrient deficiencies have been shown to lead to congenital abnormalities and birth defects in babies.
Additionally, gestational undernutrition has been shown to raise the offspring’s susceptibility to chronic disease in adulthood, including diabetes, hypertension, coronary artery disease and stroke. (1)
Prenatal supplementation might reduce maternal morbidity and mortality directly by treating a pregnancy-related illness or indirectly by lowering the risk of complications at delivery. Folate and iron are the two nutrients that have been shown to be the most crucial supplements during pregnancy. (2)
Is it possible to fulfill all of your nutritional needs during pregnancy with a healthy diet alone? Read on to find out more about the most important nutrient needs during pregnancy, and I’ll also tell you what to look for when choosing the best over-the-counter prenatal vitamins.
Common Deficiencies
Iron-deficiency anemia is extremely common in pregnancy. When you’re pregnant, the amount of blood in your body increases until you have almost twice as much as normal. This causes your body to require more iron to make more hemoglobin for all that extra blood. You also need more iron for your growing baby and placenta.
Although an iron deficiency is the most common reason for nutritional anemia in the world, folate deficiency is considered as the second most common cause and often co-exists with iron deficiency, which is one of the reasons folate is so crucial to a healthy pregnancy.
Pregnant women can be low in omega-3 fatty acids, especially when omega-3 foods aren’t consumed on a regular basis. If you don’t eat fish or other foods high in omega-3 fatty acids, then your health care provider will likely recommend omega-3 fatty acid supplements in addition to prenatal vitamins.
If you have previously given birth to a baby with a neural tube defect, then your health care provider might likely suggest taking a higher dose than normal of a folate supplement before and during any subsequent pregnancies. (3)
If you’re a pregnant vegetarian and don’t consume animal products, then the nutrients that you’ll likely need to supplement include vitamin B12, zinc, iron and omega-3 fatty acids like DHA. (4) You can look for supplements that contain these vitamins plus DHA from a vegetarian source like algae.
Best Prenatal Vitamins
A pregnant woman’s energy requirements increase by an estimated 300 calories per day during pregnancy, while protein requirements go up to 75 grams per day.
Additionally, her need for certain nutrients increases as well. Prenatal vitamins typically contain the full spectrum of vitamins and minerals, but these are the ones you definitely want to make sure you get enough of during your pregnancy: (5)
- Folate (aka B9 or Folic Acid): 600 micrograms–800 micrograms per day before conception and throughout pregnancy. Folate is a B vitamin that helps prevent neural tube defects as well as serious abnormalities of the brain and spinal cord. Folate is preferable over folic acid, which is the synthetic form of folate commonly found in many fortified foods and supplements. It’s commonly recommended to start supplementing with folate three months before conception. Folate can also help prevent anemia.
- Iron:Â 27 milligrams per day. Iron is essential for the delivery of oxygen to the baby and prevents anemia in the expecting mom. Iron can also help prevent premature delivery.
- Calcium: 1,000 milligrams per day. Calcium helps build your baby’s bones and prevents bone loss in the mother. Calcium also helps your circulatory, muscular and nervous systems run normally — all the more reason that calcium deficiency is dangerous for pregnant women and their unborn children.
- Vitamin D: 600 international units per day. Vitamin D also helps build your baby’s teeth and bones. Levels also affect a pregnant woman’s blood pressure, immunity, mood and brain function, which is why you want to prevent vitamin D deficiency.
In general, you can opt for a prenatal vitamin that contains all of these key nutrients plus many others. Prenatal vitamins now come in a variety of forms, including tablet, capsule, chewable or powdered drink mix.
Whichever one you choose, the best prenatal vitamins are those that are whole food-based, gluten-free and non-GMO. When you take a supplement that’s derived from whole foods, your body is more likely to have an easier time digesting and using the nutrients in that supplement.
Organic prenatal vitamins are easily available at stores and online these days as well. You can also find prenatal vitamins with DHA included so you can have less prenatal pills to consume on a daily basis. Most experts recommend consuming 200 to 300 milligrams of the omega-3 fatty acid known as DHA per day. (6)
Eating fatty fish at least twice a week is another way to satisfy your omega-3 fatty acid needs without supplements.
Food Sources
Folate-rich foods:Â Leafy green vegetables, asparagus, citrus fruits, dried beans and peas are all great sources of naturally occurring folate.
Iron-rich foods: Lean red meat, poultry, fish, beans, dark leafy greens, artichokes and prunes are great sources of iron. Dietary iron is absorbed more easily if iron-rich foods are eaten with vitamin C foods, such as citrus fruits and tomatoes.
Calcium-rich foods: Yogurt, kefir, goat cheese, sardines, white beans, sesame seeds, okra and collard greens are all great sources of calcium.
Vitamin D-rich foods: Some good choices include mackerel, salmon, whitefish, sardines, portobello mushrooms (exposed to UV light) and eggs.
Is Diet Enough?
Prenatal vitamins are never a replacement for a healthy diet, and they work best when they’re taken as a part of an overall healthy diet.
The American Pregnancy Association advises that pregnant women should only take vitamin supplements under a health care provider’s direct recommendation. Prenatal vitamins are meant to ensure that a pregnant woman is getting enough vital nutrients on a daily basis. (7)
So, what if you want to get all of your nutrients from real foods and skip the supplements? Every pregnant woman is different, but generally speaking the American Congress of Obstetricians and Gynecologists recommends that all pregnant women take 600 micrograms of folate and 27 milligrams of iron daily.
It does specify that the 600 micrograms of folate daily can come from all sources, but it may be hard to get the recommended amount from food alone. (8) That’s why folate supplementation is the No. 1 recommendation for pregnant women.
When it comes to iron during pregnancy, you need about double the amount that a non-pregnant woman needs. This additional iron is key since it assists your body in making more blood to supply oxygen to your baby. The daily recommended dose of iron during pregnancy is 27 to 30 milligrams, which is found in most prenatal vitamin supplements.
This iron requirement is actually obtainable without supplements if you can manage to consume enough iron-rich foods on a daily basis. Plus, in women who already have normal iron levels, taking iron supplements as a precautionary measure most likely does not have any health benefits. (9)
Every pregnant woman is going to have a pregnancy that’s completely unique to her. Aside from folate and iron, the need for other supplements during pregnancy can depend on factors such as your natural body chemistry, diet and health history. (10)
Opinions do vary, but many experts believe that even pregnant women with superior nutritional profiles should opt for a complete prenatal vitamin to cover any gaps in their diets. You can ask your health care provider for a thorough blood test that will show you if and where you have any nutrient deficiencies. This can help guide you toward the best prenatal supplements for your specific needs.
You also might be wondering if diet is enough because your prenatal vitamin makes you nauseous or aggravates your morning sickness, both of which are known to commonly happen to pregnant women. One way to prevent this is to take your prenatal vitamin with food, which is a good idea even if you don’t get nauseous when taking it on an empty stomach.
Related: The Best Postnatal Vitamins for Mom and Baby
Overdosing Risks
Most pregnant women are typically concerned with getting enough nutrients, but it’s also just as important for the health of your baby not to overdose on nutrients either. Many prepackaged and vitamin-fortified smoothies, bars, and other food and drink products might seem like healthy choices when you’re pregnant, but that might not always be the case.
You might think the more vitamins and minerals I get, the better for my baby. However, when you’re already taking a prenatal vitamin and eating an overall healthy diet, it’s especially important to keep track of any other added nutrients in your diet.
While excess water-soluble vitamins, such as folate and vitamin C, are excreted through urine, fat-soluble vitamins like vitamin A, D, E and K are easier to overdose on. For example, too much vitamin A has been shown to cause birth defects, including malformations of the eyes, skull, lungs and heart. (11)
So choose your food and drink wisely because you certainly don’t want to overload yourself or your developing baby.
Side Effects
Prenatal vitamins can cause nausea or aggravate morning sickness. If this occurs, you should try taking your vitamin during a meal. If that doesn’t help, you should talk to your doctor about taking chewable vitamins in place of the large prenatal vitamins.
If you forget to take your daily dosage at the usual time, take a dose as soon as you remember. However, if it’s almost time for your next dose then just wait until then and take a regular dose. You should not take extra prenatal vitamins to make up for a missed dose. (12)
There are many drugs that can interact with prenatal multivitamins. Be sure to tell your doctor about any other medications as well as natural supplements you currently take.
Less serious side effects of prenatal vitamins include dark stools or constipation (as a result of the iron content) or mild nausea. Most women experience constipation from iron, but you can combat it by drinking plenty of water and eating lots of fiber. Prunes and figs can also provide natural constipation relief.
Talk with your doctor if you experience any of these, and definitely tell your doctor right away if you notice any other additional or more serious side effects.
Final Thoughts
A high-quality prenatal vitamin can be a helpful addition to an overall healthy diet. Before and during pregnancy, folate has been shown to be the most important supplement to take during pregnancy, but all vitamins and minerals are important to the health of a pregnant woman and her developing child, most of which can be obtained from healthy food choices on a daily basis. However, some nutrients like folate, iron, calcium and vitamin D are especially important to the development of a fetus but can be harder to get at needed levels from diet alone. That’s when supplements can be helpful in filling in common dietary gaps.
In general, most health care providers recommend a prenatal vitamin for the duration of your pregnancy. It’s a smart idea to have your nutrient levels checked to see exactly where there are deficiencies, if any. Once you obtain this knowledge via blood work, you can make more informed and more health-promoting decisions when it comes to your diet and prenatal supplements. Blindly taking supplements or having an overly excessive intake of nutrients is not good for a pregnant woman and can actually have negative health consequences on her baby.
Always focus on improving your diet through whole foods as much as possible and look at prenatal supplements as secondary insurance to optimize your health and the health of your little one.