This sheet is about exposure to zinc from diet and dietary supplements in pregnancy and while breastfeeding. This information is based on published research studies. It should not take the place of medical care and advice from your healthcare provider.
What is zinc?
Zinc is an essential nutrient. This means the body cannot make zinc, so people need to get zinc from other sources. Zinc is naturally found in some foods such as meats and seafood and is added to some cereals. Zinc is also available as a dietary supplement and found in certain homeopathic products marketed for colds. Some denture adhesives also contain zinc.
Talk with your healthcare providers about all vitamins and supplements that you take. Have the bottles or photos of the labels with you so that all ingredients and their amounts can be reviewed. Products that contain herbals are typically not recommended during pregnancy. For more information on herbal products please see our fact sheet at: https://mothertobaby.org/fact-sheets/herbal-products-pregnancy/.
How much zinc do I need?
The Recommended Dietary Allowance (RDA) is the amount people should aim to get each day. It is not recommended to take more zinc than the RDA in a day. The Tolerable Upper Intake Level (UL) is the dose at which people can start to have side effects. RDAs and ULs are there to help guide us in getting enough of a good thing but also to keep us from getting too much of a good thing.
| Recommended Daily Allowance (RDA) | Upper Limit (UL) | |
| 14 to 18 years old and pregnant | 12 mg per day | 34 mg per day |
| 19 years old or older and pregnant | 11 mg per day | 40 mg per day |
When reviewing amount of zinc, it is important to include amounts from foods, drinks, and supplements. There are resources available online that list amounts of zinc typically found in foods. Labels on supplements will list the amount of zinc in the product.
Most people get the RDA of zinc from a balanced diet. It is unlikely that a person would get too much zinc from foods and drinks. People who do not eat meat or seafood, have had bariatric surgery (such as gastric bypass), have medical conditions that might affect how their body absorbs nutrients (such as cancer, eating disorders, kidney disease, malabsorption, or substance misuse), or have exposure to cigarette smoke, should talk with their healthcare providers about their specific nutritional needs.
I take zinc. Can it make it harder for me to get pregnant?
Some studies have suggested that having zinc blood levels that are too low might make it harder for a woman to get pregnant. Studes have not been done to see if taking extra zinc (above the UL) can make it harder to get pregnant. If a woman is getting the recommended amounts of zinc (between the RDA and UL) it is unlikely to make it harder to get pregnant.
Does taking zinc increase the chance of miscarriage?
Miscarriage is common and can occur in any pregnancy for many different reasons. Some studies have suggested that having zinc blood levels that are too low might increase the chance of miscarriage. Studies have not been done to see if taking extra zinc (above the UL) can increase the chance of miscarriage. If a woman is getting the recommended amounts of zinc (between the RDA and UL) it is unlikely to increase the chance of miscarriage.
Does taking zinc increase the chance of birth defects?
Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like zinc, might increase the chance of birth defects in a pregnancy. If a woman is getting the recommended amounts of zinc (between the RDA and UL) it is unlikely to increase the chance for birth defects.
Some studies have suggested that women with zinc blood levels that are too low might have a higher chance of having a pregnancy with a neural tube defect (an opening anywhere along the spine). It is not known if taking extra zinc (above the UL) can increase the chance of birth defects.
Does taking zinc in pregnancy increase the chance of other pregnancy-related problems?
Some studies have suggested that having zinc blood levels that are too low might increase the chance of pregnancy-related problems such as: low birth weight (weighing less than 5 pounds 8 ounces [2500 grams] at birth), stillbirth, high blood pressure, and preeclampsia (high blood pressure and problems with organs, such as the kidneys, which can lead to seizures (called eclampsia)).
Studies have not been done to see if taking extra zinc (above the UL) can increase the chance of other pregnancy-related problems. If a woman is getting the recommended amounts of zinc (between the RDA and UL) it is unlikely to increase the chance for other pregnancy-related problems.
Does taking zinc in pregnancy affect future behavior or learning for the child?
Studies have not been done to see if zinc intake below the RDA (too little) or at doses higher than the UL (too much) can increase the chance of behavior or learning issues. If a woman is getting the recommended amounts of zinc (between the RDA and UL) it is unlikely to affect future behavior or learning for the child.
Breastfeeding while taking zinc:
Zinc is a normal part of breastmilk. It is normal for zinc levels in the breast milk to slowly drop over time regardless of the amount of zinc that the mother gets. Women who are breastfeeding should continue to get the daily recommended amount of zinc. The RDA for breastfeeding is different from pregnancy. See the chart below for the Recommended Daily Allowance (RDA) and a Tolerable Upper Intake Level (UL) of zinc while breastfeeding.
| Recommended Daily Allowance (RDA) | Upper Limit (UL) | |
| 14 to 18 years old and breastfeeding | 13 mg per day | 34 mg per day |
| 19 years old or older and breastfeeding | 12 mg per day | 40 mg per day |
Studies have not been done to see if extra zinc (above the UL) can affect breast milk or the breastfeeding child. Be sure to talk to your healthcare provider about all your breastfeeding questions.
People who do not eat meat or seafood, have had bariatric surgery (such as gastric bypass), have medical conditions that might affect how their body absorbs nutrients (such as cancer, eating disorders, kidney disease, malabsorption, or substance misuse), or have exposure to cigarette smoke, should talk with their healthcare providers about their specific nutritional needs.
If a man takes zinc, could it affect his fertility or increase the chance of birth defects?
Some studies have suggested that having blood zinc levels that are too low might increase the chance for problems with fertility (ability to get a woman pregnant). Zinc supplementation might help to improve fertility for some men but not for others. It is not known if extra zinc (above the UL) can affect a man’s fertility. Studies have not been done to see if too much or too little zinc intake for men could increase the chance of birth defects. In general, exposures that fathers or sperm donors have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.
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