Some people can experience nausea when taking multivitamins. This might be because of when they take them or because they are consuming too much of a certain vitamin.

Multivitamin supplements are a popular way for people to try and meet daily recommendations for important nutrients.

While they are generally safe for healthy people to take, some may report gastrointestinal symptoms, such as nausea, when using them.

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There are a few possible reasons why taking a multivitamin might cause someone to feel nauseous.

Taking the multivitamin on an empty stomach

While some medications require people to take them on an empty stomach, this is not true for multivitamins.

As the nutrients in a multivitamin supplement are highly concentrated, they can be irritating to a stomach if nothing else is present to reduce their impact.

In addition to upsetting the stomach, taking multivitamins on an empty stomach is also less efficient in terms of absorption. Certain vitamins require the presence of fat for the body to absorb them properly. As a result, people will miss out on a multivitamin’s benefits by taking ones that contain these fat-soluble vitamins on an empty stomach.

Typically, people should take iron supplements on an empty stomach. However, it can sometimes still lead to gastrointestinal distress even when taken as recommended.

If the multivitamin does not contain iron, they may wish to examine the ingredients to identify the presence of herbal supplements, as these may be the cause of a person’s gastrointestinal symptoms.

Getting too much of certain vitamins

Research suggests that taking multivitamins can increase people’s tendency to consume more of certain nutrients than they need.

One reason for this may be that people who take multivitamins tend to have higher intakes of vitamins and other nutrients from their diets than those who do not take them.

Excessive levels of certain vitamins can lead to nausea and other gastrointestinal symptoms. This can occur with getting too much vitamin C, calcium, and vitamin A, for example.

Other ingredients

Other ingredients present in multivitamins could also be behind some cases of nausea.

In one older study, for example, a weight loss program received increased reports of nausea and vomiting from its users after changing the multivitamin the program provided.

The researchers noted the new multivitamin included an added ingredient not present in the original supplement.

If someone is feeling nauseous after taking a multivitamin, here are some steps that could help relieve symptoms:

  • eating a smaller amount of food
  • taking regular sips of a cold drink, such as water
  • drinking ginger or peppermint tea
  • getting fresh air

When it comes to eating, it is best to avoid eating too quickly. Also, try to avoid strong-smelling foods or those that are fried, greasy, or spicy.

Do not lie down immediately after eating, and avoid wearing clothing that is too tight around the stomach and waist.

Learn more about home remedies for nausea.

It is important to eat something around the same time as taking multivitamins to reduce the risk of nausea.

Eating something that contains fat will also make it easier for the body to absorb any fat-soluble vitamins that may be present in the supplement.

People can also try out different forms of multivitamins to find one that works for them.

Some multivitamins come with doses that are much higher than the amounts adults need each day. These could increase someone’s risk of consuming more of a particular vitamin than they need.

Different multivitamins also contain different ingredients, which may provoke different reactions in different people.

People should be mindful of the levels of certain vitamins they get from their diet. Research suggests many people who take multivitamins are those who already get a lot of essential nutrients from their diet.

If someone is already following a healthy diet and does not fall into one of the groups of people who are at risk of certain vitamin deficiencies, it may be worth reassessing whether or not a multivitamin is necessary.

People who may benefit most from multivitamins include:

  • vegetarians and vegans
  • people who are pregnant or could become pregnant
  • adults aged 60 years or above

Learn more about research into the impact of multivitamins.

People should stop taking a multivitamin if it regularly makes them feel unwell and steps to prevent nausea are not working. There will always be alternative ways for people to get the necessary nutrients.

If a multivitamin contains high levels of particular vitamins, certain people should avoid taking them.

  • Smokers should avoid high doses of vitamin A and beta carotene as they can increase the risk of lung cancer.
  • Pregnant people should avoid high doses of vitamin A as it can increase the risk of congenital anomalies.
  • People taking blood thinning medication should discuss doses of vitamin K with a doctor, as it can reduce the effectiveness of these drugs.

Is it normal for multivitamins to make you nauseous?

While many people take multivitamins without experiencing any side effects, research from 2017 shows some people do feel nauseous or experience other gastrointestinal symptoms.

What happens if you take vitamins on an empty stomach?

If someone takes vitamins on an empty stomach, they can end up irritating their stomach. This can lead to feelings of nausea and other related symptoms.

Taking vitamins on an empty stomach also makes it harder for the body to absorb certain vitamins.

How long does nausea from taking multivitamins last?

Nausea does not tend to last long. Food generally takes 1.5 to 2 hours to move from the stomach to the intestine. After this time, the nausea should also pass.

Why do vitamins make me nauseous even with food?

Multivitamins can make people feel nauseous with food if they are consuming higher levels of certain nutrients than they need.

People may feel nauseous after taking a multivitamin for several reasons. They may have taken the supplement on an empty stomach or exceeded the recommended dosage for a particular vitamin. A specific ingredient could also be behind the reaction.

While certain people may benefit from taking a multivitamin, the best way for most people to get their essential nutrients is through diet. Food sources of vitamins also provide other beneficial ingredients, such as fiber, fat, and protein, which are vital for good health.

It is also worth noting that supplements do not receive the same scrutiny and regulation as medicines. The Food and Drug Administration (FDA) does not regulate or approve their use, so people should be mindful of what they might contain before using them.