Prenatal Vitamin Limits

Prenatal vitamins and minerals such as iron, calcium, and folic acid are vital for proper fetal growth, development, and healthy adult living. To help increase your chances of creating a healthy environment in which your baby can develop, it is important that you establish a well-balanced diet and exercise routine before you get pregnant.

If you choose to supplement your diet with synthetic nutrients, be sure to keep track of the daily amounts you take, and let your health care provider know. It is possible to overdose on certain vitamins and minerals, which could have adverse effects on you and your growing baby.
You should be well educated on what the recommended amounts are for prenatal vitamins and minerals during pregnancy.

Prenatal Vitamin and Mineral Sources

If your diet consists of unprocessed foods, fruits, a colorful variety of vegetables, whole grains, lentils, and plenty of water, then you likely have sufficient vitamins and minerals already in your body.  As long as you are eating a well-balanced diet, you need not fear to overdose on nutrients found naturally in foods.

However, some studies have shown symptoms of toxicity after a large consumption of animal organs, such as liver.
Supplements (synthetic vitamins and minerals) are a different story. They contain higher doses of nutrients in a concentrated form, which can be detrimental if taken in improper amounts. Always let your health care provider know what nutritional supplements you are taking.

Prenatal Vitamin Limits & Recommendations

Prenatal vitamins consist of a variety of vitamins and minerals. During pregnancy, a woman’s daily intake requirements for certain nutrients, such as folic acid (folate), calcium, and iron, will increase.  If you are pregnant (or trying to conceive) and considering taking a prenatal vitamin, carefully read the nutritional labels and familiarize yourself with terms like RDA and UL.

  • RDA = Recommended Dietary Allowance. The RDA represents the amount of nutrient needed to maintain good health for most people.
  • UL = Tolerable Upper Intake Levels. The UL represents the highest amount most people can take without experiencing potentially harmful effects.

In general, avoid taking extra prenatal vitamins or multivitamins with dosing in excess of what you need on a daily basis. High doses of some vitamins may be harmful to your baby. For example, extra vitamin A during pregnancy can potentially cause harm to your baby.

Taking more than twice the RDA of any nutrient should be avoided during pregnancy. If you are taking additional supplements, you should be aware of the signs and symptoms of overdose.

The Differences Between Fat-soluble and Water-soluble Vitamins

Fat-soluble vitamins are stored in your body. If you ingest more than your body needs, excess fat-soluble vitamins are stored in your liver and body fat. This can lead to toxic side-effects that wreak havoc on you and your baby.

Water-soluble vitamins are not stored in your body but are dissolved in water and excreted by urine on a regular basis.

If you ingest an overdose of a water-soluble vitamin, the exceeded quantities will be flushed from your body. However, overdose can still be dangerous because of potentially irritating effects the vitamins can have on your digestive system.

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Compiled using information from the following sources:

  • Natural Standard, https://www.naturalstandard.com/
  • Jellin JM, Gregory PJ, Batz F, Hitchens, K, et al. Pharmacist’s Letter/Prescriber’s Letter Natural Medicines Comprehensive Database. 4th ed. Stockton, CA: Therapeutic Research Faculty; 2002: pg 735, 1274, 1281, 1287 and 1379.
  • Williams Obstetrics Twenty-Second Ed. Cunningham, F. Gary, et al Ch 8.
  • Mayo Clinic