Pregnant and worried about getting enough iron? As a registered dietitian, I’ll walk you through everything you need to know about iron during pregnancy including a list of iron-rich foods.
As a mom of 3, and someone who has been through 3 pregnancies myself, I’m very familiar with the worries, questions and challenges that come along with growing a little human…including nutrition-related worries! Even as a dietitian, I wondered if I was getting what I needed nutrition-wise to grow a healthy baby. Iron is one of those nutrients that you often hear about when it comes to pregnancy and one that expectant moms often wonder about. Iron definitely is one of those nutrients of concern when you’re pregnant, and one that you’ll want to make sure you’re getting enough of. In this post, I’ll walk you through everything you need to know about iron for pregnancy!
Why is iron important for a healthy pregnancy?
Everybody (pregnant or not) needs iron daily to maintain healthy blood cells and move oxygen from your lungs to organs and tissues. During pregnancy, your iron needs almost double! This is because your body needs iron to make extra blood to support the growth needs of you and your developing baby. Iron is a key component of hemoglobin, a protein in red blood cells that carries oxygen around your body, and through the placenta to your baby. Without enough iron, your body will be unable to make enough red blood cells, leading to a condition called “iron deficiency anemia”. This can cause you to feel tired, weak, and may also lead to complications with your baby’s growth, brain development and an increased risk for preterm birth.
Sources and types of iron:
There are two types of iron that we absorb from the food we eat:
- Heme Iron is more bioavailable (meaning it is absorbed more easily by the body) and comes from animal food sources such as beef, pork, chicken, turkey, organ meats, fish and shellfish.
- Non-heme Iron is less bioavailable than heme iron (meaning it is not as easily absorbed) and comes from plant food sources such as chickpeas, beans, lentils, tofu, nuts/seeds, whole grains, fortified cereal products and dark leafy greens.
Whether you consume heme, non-heme or both types of iron is great!
Can I do anything to improve my iron absorption?
Yes! There are a variety of things you can do to improve your absorption of iron AND prevent the malabsorption of this mineral.
- Vitamin C rich foods help to release non-heme iron from inhibitors (such as polyphenols, phytates and calcium) that bind iron and prevent its absorption. Try eating vitamin C rich bell peppers or strawberries with your dark leafy green (rich in non-heme iron) salad to improve its absorption. Another example may be to have some vitamin C rich orange juice with your plant protein-based meals such as a lentil meatloaf or tofu rice bowl.
- Soak legumes (chickpeas, beans, lentils) and unrefined grains (quinoa, barley, rice) overnight to help remove some of the phytates present that inhibit iron absorption.
- Drink coffee and tea in-between meals versus with meals. The polyphenols in coffee and tea can bind to iron in your food, preventing its absorption. Remember that you should be careful with the amount of caffeine you consume during pregnancy and the types of teas you consume in pregnancy too!
- Consume calcium-containing foods (such as milk cheese and yogurt) separate from your iron supplement if you have iron deficiency anemia. Calcium may bind to the iron in your supplement reducing its absorption.
- Cook your food in cast-iron cookware as often as possible to add more iron to the food you prepare!
How much iron do you need during pregnancy?
Your body’s iron needs are almost double what they were prior to pregnancy; adding up to a whopping 27 milligrams of iron required each day! It can be hard to reach this amount of iron through eating food alone (especially with pregnancy nausea or food aversions). You can feel some comfort in knowing that most prenatal multivitamins will contain close to or fully cover the 27mg of iron per tablet.
High iron foods to avoid during pregnancy:
Some iron-rich foods may actually be safer to avoid during pregnancy. Avoid these high-iron foods to reduce the risk of foodborne illness and other complications during pregnancy:
- Raw or undercooked meat and poultry.
- Raw fish, shellfish (such as oysters) and raw sushi.
- Uncooked deli meats straight from the package (i.e., slices of bologna, roast beef, ham or turkey etc.). One option is to heat deli meat until steaming hot in the microwave to kill off any pathogenic bacteria that pregnant women are more vulnerable to.
- Raw or undercooked eggs. Cook eggs until the whites are opaque and the yolks are no longer runny.
Symptoms of iron deficiency anemia in pregnancy:
Iron deficiency anemia in pregnancy is most often a result of heightened iron requirements not being met through food intake or supplementation. There may be other underlying causes such as excessive blood loss or malabsorption issues which would need to be identified by your doctor. Make sure to attend regular prenatal checkups so your doctor can monitor your risk for iron deficiency, and promptly provide treatment as required throughout your pregnancy.
Symptoms of iron deficiency anemia include:
- Weakness and fatigue
- Pale skin
- Restless leg syndrome
- Hair loss
- Sore tongue
What iron supplements can you take when pregnant?
Most expectant mothers will take iron as a part of their prenatal multivitamin and mineral supplement. Typically, these supplements will contain between 15-27 mg of iron per tablet. Make sure to look for a Natural Health Product Number (NPN#) on the label to ensure that Health Canada has approved the prenatal supplement for its safety and efficacy of ingredients. Avoid the fancy-looking prenatal supplements in health food stores or online that contain herbs or other ingredients (and do not have an NPN#). Here are some examples of common, effective and safe prenatal multivitamins available on the market:
If you have questions or concerns about your prenatal multivitamin, do not hesitate to ask your doctor or registered dietitian.
Is my iron supplement making my pregnancy symptoms worse?
Sometimes the large amount (or type) of iron in your prenatal supplement can lead to upset stomach, constipation and can even worsen pregnancy nausea. Here are some strategies and alternatives that may help to reduce these side effects:
- First try taking your prenatal supplement at a meal or before you go to sleep. Sometimes this is enough to prevent these side effects.
- If this doesn’t work, ask your doctor about a liquid or chewable supplement you can try.
- You can also inquire about a prenatal supplement that splits the iron dosage in half so that you take a smaller amount of iron at 2 separate times during the day.
- Ask your doctor about switching to a polysaccharide iron supplement, which has little to no gastrointestinal side effects such as stomach upset and constipation.
- If nothing else works, you can ask your doctor about trialing a prenatal supplement that doesn’t contain iron for a period of time, while they continue to monitor your iron status. Keep an eye on how you are feeling and reintroduce an iron supplement further down the line when your pregnancy nausea and stomach symptoms begin to improve.
- Your doctor may alternatively prescribe iron infusions (directly into your bloodstream) versus taking it by mouth to avoid negative gut symptoms.
Yes, it is possible to take too much iron during pregnancy. The upper limit of iron added up from both food and supplementation is 45mg per day. Excessive iron supplementation may lead to troubling side effects such as nausea, vomiting, severe abdominal pain, inflammation of the stomach lining and ulcers. Too much iron can also reduce absorption of the essential mineral, zinc. However, if you have been diagnosed with iron deficiency anemia, your doctor may prescribe higher levels of iron supplementation (over the upper limit) until your blood levels are brought back to normal.
If you eat a mostly or exclusively plant based diet, your iron is coming from non-heme iron sources, which like mentioned earlier, is the less absorbable form of iron. Since plant-based iron is not as easily used by the body, you are at higher risk for iron deficiency during pregnancy when following a vegetarian or vegan diet. However, there are a few things you can do to improve your iron absorption, answered in the next question below.
Your doctor may also suggest an extra iron supplement on top of your prenatal supplement to help fill in this nutrient gap. Be sure to talk to your doctor before taking any extra supplements.
Yes, iron supplements may interact with certain medications and supplements. Calcium supplements may interfere with iron supplement absorption so taking these minerals at separate times of the day may be beneficial to you especially if you are at risk of iron deficiency.
Iron supplements may also have adverse reactions with medications used treat hypothyroidism, heart burn, Parkinson’s disease and restless leg syndrome. Review your medications and supplements with your doctor or pharmacist to address these interactions and sort out the best medication/supplement routine for your body during pregnancy.
Try this easy iron rich recipe
- Your Guide to a Healthy Pregnancy – Canada.ca
- Food to Grow On
- Iron – Health Professional Fact Sheet (nih.gov)
- Iron (albertahealthservices.ca)