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Do Prenatal Vitamins Make Us Gain Weight?


Prenatal vitamins during pregnancy are a universal recommendation, but there are also many reasons you might consider taking prenatal vitamins while not pregnant; for the health benefits; to prepare your body for pregnancy (we have a vitamin just for that!); for long, healthy nails and hair—the list goes on. Whether your motivation is a healthy pregnancy or thicker mane, we have a sneaking suspicion that you might be asking another question: will prenatal vitamins make me gain weight? Because no question is trivial around these parts, we checked in with our Dr. Banafsheh Bayati, M.D., board-certified OB/GYN, for the skinny, no pun intended. 

vitamin ingredients

Do prenatal vitamins make you gain weight? 

“The answer is no! But taking prenatal vitamins can impact weight as they affect different processes in the body including your metabolism. Prenatal vitamins may be taken at a time when your weight is increasing due to pregnancy or they may be taken at a time when you are focusing on improved nutrition and health and possibly working on weight management.  Thus it depends on the individual. Some studies show an association between lower body mass index in individuals who take multivitamins regularly. But again, it could be simply because such individuals are also mindful in regards to nutrition and exercise. In general, a prenatal vitamin should supplement a healthy diet and an active lifestyle,” Dr. Bayati advises. 

Is there any one element of a prenatal that could make you gain weight, in excess?

Alright so the answer is no, but we can’t just leave our curiosity at the door that quickly. We have to wonder, is there any ingredient at all that could be associated with weight fluctuations? According to Dr. Bayati, “the iron supplement in many prenatal vitamins can cause constipation and bloating.  This can make you feel very uncomfortable and certainly heavier in pregnancy. Thus it is important to have a diet rich in iron and Vitamin C along with a smart prenatal that includes the right balance between iron, Vitamin C, calcium, and magnesium to ensure the best absorption with the least side effects.” 

Also keep in mind that “chelated forms of iron can improve iron absorption with less side effects and adding Vitamin C to the prenatal aids this absorption even further. Certain types of magnesium (particularly magnesium citrate) and the right balance of calcium can also help with the reduction of undesired GI symptoms from iron supplementation. Omegas can also be helpful in reducing any undesired GI changes.”

Our Core Prenatal is formulated with Ferrochel™ ferrous chelated format to allow for optimal absorption and limited constipating side effects.

Have any other burning questions for our panel of experts? We’ll ask them in an upcoming post. Plus, shop vitamins for your exact stage of womanhood now to give your body extra nutrition.

This article is for informational purposes only. It is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and we recommend that you always consult with your healthcare provider. To the extent that this article features the advice of physicians or medical practitioners, the views expressed are the views of the cited expert and do not necessarily represent the views of Perelel.

Written by Jessica Lopez. Jessica Lopez is a freelance writer, digital content creator, and new mother. She has covered all lifestyle topics ranging from bridal to beauty for publications including Brides Magazine, Byrdie, THE/THIRTY, and more. Walking wide-eyed into motherhood has inspired her to connect with other parents through her writing and shared experience. You can follow more of her journey @Jessica.H.Lopez