why do vitamins make me nauseous

Why Do Vitamins Make Me Nauseous?

Taking vitamins is an investment in your health—supplements can help fill nutritional gaps in your diet, potentially reduce your risk of deficiencies, and support your overall wellbeing.1 (And if you're taking stage-specific vitamins like prenatals, they can do even more heavy-lifting than that.)

But if you sometimes feel temporarily nauseous after taking your vitamins, or if they give you acid reflux or causes stomach cramps, don’t panic: It’s fairly common, and there are a few things you can do to prevent it.

Here’s everything you need to know about why your vitamins may be making you feel nauseous, and how to reap their benefits without suffering the unpleasant side effects. 

Why do my vitamins make me feel nauseous?

There are a few potential culprits behind vitamin-related nausea:

  • You're taking your supplements on an empty stomach.
  • You're sensitive to certain nutrients.
  • Your vitamin's ingredients aren't optimized to be gentle on the stomach.

In other words, there are some optimizations you can make to your own routine to make stomaching vitamins easier—but it also comes down to the brands and formulas you choose.

Nausea culprit: You're taking your supplements on an empty stomach.

The solve: Always take your vitamins with food and water.

Taking supplements on an empty stomach can cause gastrointestinal (GI) distress like nausea, diarrhea and stomach cramps—especially if they contain calcium, vitamin C or iron, which are particularly prone to irritating the stomach lining.2

Taking your vitamins with a meal can help minimize these symptoms by increasing the body’s ability to absorb them. If you don’t eat breakfast, save your supplements for whenever you do eat. Eating even small amounts of food prior to taking supplements can reduce the risk of stomach upset or nausea.

The tricky thing about nutrients like iron is that to achieve optimal absorption, they should be taken on an empty stomach. However, for some people, taking them without food is to blame for some of the side effects.

If taking iron supplements on an empty stomach causes you to feel sick, it’s okay to take them with a small amount of food. Just avoid consuming milk, foods or drinks with caffeine, and high fiber foods like whole grains and raw vegetables with your iron supplement, as these can hinder absorption or cause unpleasant side effects. The same is true of calcium supplements and antacids—wait at least two hours after taking these before taking your iron supplement. Some experts recommend taking your iron pill with foods rich in vitamin C, like citrus fruits, or a vitamin C supplement, since this nutrient helps enhance iron absorption.3 

Nausea culprit: Certain nutrients are tougher on the stomach.

The solve: Opt for vitamin brands that choose gentler nutrient forms.

A common offender, for example, is iron—iron deficiency is the most common nutritional deficiency worldwide among women of reproductive age and throughout pregnancy, which is why supplementing iron is so important. But it also tends to be one of the trickiest nutrients to stomach. It's why we only use Ferrochel® Iron Bisglycinate Chelate in our Perelel formulas: the most bioavailable, and absorbable form of iron that’s easiest to tolerate and digest. We only use ferrochel® iron here at Perelel so your packs are gentle on the stomach but still effectively deliver the nutrients your body needs.

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Nausea culprit: You're overdoing it on nutrients.

The solve: Instead of cobbling together a bunch of different vitamin formulas yourself, stick to a comprehensive, doctor-backed routine that's dosed out for you.

It might seem like "more is more" when it comes to good-for-you nutrients—but the truth is that nutrient overload is definitely a thing. Unlike water-soluble vitamins, which are excreted through urine when taken in excess, fat-soluble vitamins (vitamins A, D, E and K) leave deposits in your body. And overdoing it on these nutrients can occasionally cause stomach upset.4

It's why we consulted with our medical panel of leading doctors and clinical research to create comprehensive, stage-specific vitamin routines, with quality ingredients in the doses you actually need—nothing more, and nothing less.

How long does nausea last?

The duration of symptoms varies from person to person, and depends on the type and dose of vitamins taken.

Some experts say that nausea and irritation should subside within two to three hours of consumption—that’s the amount of time it takes for vitamins to pass into the intestines.

If you’re experiencing nausea that doesn’t subside after a few hours or once you’ve eaten, you may want to consider reaching out to your healthcare provider to ensure you don’t have an underlying health condition.

Other Ways to Prevent Nausea from Vitamins

1. Don’t take them before exercise.

Taking supplements right before your spin class or 5K training run is a bad idea—all that jostling can increase stomach acids, causing heartburn or reflux.

Intense exercise, in particular, can induce acid reflex. So adding a nutrient like vitamin C, which can promote stomach acid production, means you’ll have a whole lot of acid in your stomach, which can contribute to feelings of sickness.5

2. Try splitting your routine. 

Our Perelel Packs were formulated with your comfort in mind, and designed to be taken in a single sitting—but if you find yourself particularly sensitive to supplements, you might consider splitting your pack between breakfast and dinner.

3. Consider your medications.

If you’re taking medication, it’s possible that it’s interacting with your supplements, causing undesirable side effects. If you suspect that this may be the case, consult with your healthcare provider for guidance.5

Want more tips for taking supplements? Learn more in our complete guide to taking vitamins, according to an OB/GYN now. 

1. Taking a Multivitamin is Shown To Fill Nutrient Gaps in our Diet | HSIS. Hsis.org.

2. Encyclopedia M, supplements T. Taking iron supplements: MedlinePlus Medical Encyclopedia. Medlineplus.gov.

3. JM R. Safety of high-level vitamin C ingestion. PubMed. 

4. - Dietary Reference Intakes for Calcium and Vitamin D - NCBI Bookshelf. Ncbi.nlm.nih.gov. 

5. Does Vitamin C and E Supplementation Impair the Favorable Adaptations of Regular Exercise?. National Library of Medicine.

6. Problems with Calcium Supplements - American Bone Health. 

7. Mixing Medications and Dietary Supplements Can Endanger Your Health. Food and Drug Administration.