Are Your Vitamins Making You Nauseous? There May Be an Easy Solution

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    While vitamin supplements can, under certain conditions, cause nausea, the solution is usually an easy one. It’s key to know what you’re taking, when, and why.

    Why does taking vitamins cause nausea?

    Most people do not meet all of their nutritional needs from food intake alone. Vitamins and supplements have proven to be helpful in filling in the nutrient gaps created by these deficiencies. Given the multitude of complex processes that have to happen synchronistically in order for the body to function optimally, no one should be surprised when complications arise. Digestive issues can impact the absorption of nutrients. Age, overall health, and other supplements or medications can create side effects. Even something as ordinary as a sensitive stomach can result in nausea when taking supplements. The important takeaway is that you know your body and the basics of supplementation in order to avoid side effects whenever possible.

    Taking vitamins on an empty stomach

    While there is no hard and fast rule on whether to take vitamins on an empty stomach or not, there is some science to impact your decision. Vitamins C and all the Bs are water-soluble and should be taken on an empty stomach with a large glass of water. Any excess that is not absorbed for use by the body will be excreted through urine each day. Minerals are also best absorbed on an empty stomach. Vitamins A, D, E, and K are fat-soluble vitamins and should be taken with food that contains fat (avocado, egg yolk, olive oil) to ensure proper absorption. Multivitamins are a blend of both and should be taken with food. Magnesium, on the other hand, is a mineral that, when taken on an empty stomach in large quantities, can have a laxative effect so it should also be taken with food. Prenatal vitamins should also be taken with food.

    Overloading on vitamins

    Supplementing with high doses can be harmful with fat-soluble vitamins because they can be stored in the body and accumulate over time. B12 is the only water-soluble vitamin that can be stored in the liver to decrease the likelihood of deficiency. Overloading on iron when not deficient can be toxic. Though vitamin C (ascorbic acid) is water-soluble, it can, when taken in large quantities, result in potential nausea, stomach distress, constipation, or diarrhea. Taking it with a small amount of food will help and only have minimal impact on absorption. It is important to consult your physician when using supplements so they can order labs to monitor certain nutrient levels over long, consistent periods of time.

    Taking too many vitamins at once

    With some vitamins and supplements, timing matters. Digestive enzymes should be taken either before or immediately after a meal. Melatonin can be sleep-inducing so it should be taken at bedtime. Magnesium helps with sleep and relaxation, so it is typically taken in early evening or at bedtime. Vitamin C helps with iron absorption so it is beneficial to take them in tandem. Water-solubles are usually taken on an empty stomach while fat-solubles need to be taken with food. Some formulas can be combined with multiple vitamins, but the most important factor is looking at the dose and making sure to take fat-solubles with some fat containing food to maximize the absorption.

    How to avoid potentially feeling sick after taking vitamins?

    Take vitamins with a meal

    If it’s a fat-soluble vitamin, it is important to take it with food that contains fat. If you cannot take it with a meal, it is okay to take it with a snack like hummus, nuts, or guacamole. The fat is necessary for maximum absorption of the vitamin. Excess amounts of vitamin C might cause digestive stress so it is okay to take it with a small amount of food.. Know your supplements, ask your physician or healthcare provider what works best for you, and read the labels.

    Taking vitamins before a workout

    If a supplement is intended to support exercise performance, the label or packaging will clearly indicate how, and when, to take it for maximum impact. Avoid taking any vitamins that are not intended to be pre-exercise supplements before working out. Taking supplements right before vigorous exercise can contribute to digestive discomfort for some people.

    Try taking vitamins at a different time of the day

    If taking multiple capsules feels overwhelming, try taking vitamins at different times of the day. The key is to be consistent with supplements and to find what works best and when for you and then develop a routine.

    Don’t take vitamins and medications at the same time

    It is best to take vitamins and medications apart from one another in order to ensure that the medication is absorbed properly. When taking other medications, it is important to consult your physician before taking new supplements.

    Final takeaways

    While it is possible to experience nausea from vitamins, the fix is often an easy solution. Fat-soluble vitamins need to be taken with food in order to maximize absorption. Failure to do so may cause digestive distress, including nausea. Water-solubles should be taken on an empty stomach, though excess amounts of vitamin C can result in digestive discomfort. It is important to know the supplement’s possible side effects, if there are any interactions with other supplements or medications, and when it is best to take them. If you have a sensitive stomach, you may be more likely to experience nausea, but the solution is usually found with a little experimentation and a consultation with your physician or healthcare provider.

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    Dr. Carla Montrond Correia ND, CNS
    Medical Content Manager
    Dr. Montrond-Correia is a licensed naturopathic physician and a certified nutrition specialist (CNS). She holds degrees from University of Bridgeport, Georgetown University, and University of Saint Joseph, and supplemented her education with internships in the health and wellness space. She's focused on research, herbal medicine, nutrigenomics, and integrative and functional medicine. She makes time for exercise, artistic activities, and enjoying delicious food.
    Our Editorial Staff
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    The Care/of Editorial Team is made up of writers, experts, and health enthusiasts, all dedicated to giving you the information you need today. Our team is here to answer your biggest wellness questions, read the studies for you, and introduce you to your new favorite product, staying up to date on the latest research, trends, and science. Each article is written by one of our experts, reviewed both for editorial standards by an editor and medical standards by one of our naturopathic doctors, and updated regularly as new information becomes available.