Created for Greatist by the experts at Healthline. Read more

Remember when you could pop a Flintstones vitamin and call it a day? That quick burst of sweet, vitamin-y goodness. A simple, uncomplicated daily wonder of supposed health. No matter the time of day… or so you thought.

Fast forward to adulthood. It turns out there’s actually some science behind the best time to take vitamins.

When is the best time to take vitamins?

Your body will absorb and process different types of vitamins differently depending on a few factors: The time of day, what’s in your stomach, and most importantly — what type of vitamin it is.

In general, try to take water-soluble vitamins (B and C) in the morning, or whenever you’re most likely to remember, and fat-soluble vitamins (A, D, E, K) with a meal for the biggest benefits.

Understanding the different types of vitamins will help you decide when to take them to maximize absorption and minimize upset stomach.

  • Multivitamins (or prenatal vitamins). These are a selection of essential nutrients combined with other binding ingredients and possibly flavoring.
  • Fat-soluble. Fat-soluble vitamins need fat to help the body process them. Excess fat-soluble vitamins are stored in your liver and the fatty tissues throughout your body. These include vitamin A, D, E, and K.
  • Water-soluble. Water-soluble vitamins are B-complex vitamins (B1, B2, B3, B6, B12, folate, biotin, and pantothenic acid) and vitamin C. You need to get your recommended amount every day because your body doesn’t store them like fat-soluble vitamins.

Research still suggests that getting your daily vitamin intake from a healthy and balanced diet is ideal, but it isn’t always easy. If you can’t make that happen or have a vitamin deficiency (or lackluster skin) — vitamin supplements are here to help.

Multivitamins

For multivitamins, it’s less about the time of day and more about consistency. Take multivitamins at the same time every day for the best absorption.

While a 2012 review of relevant studies found that there isn’t a benefit to taking multivitamins for most people, there is a type of multivitamin that has proven valuable: the prenatal vitamin.

Prenatal vitamins are designed to give you the extra folic acid and iron you need during pregnancy.

Pregnancy takes a lot out of you — including some essential nutrients. A lot of important development happens in that first month of pregnancy, so try to start taking prenatal vitamins (especially folic acid) about 3 months before becoming pregnant.

Best time to take prenatal vitamins

The best time to take prenatal vitamins is — whenever feels right for you. Some suggest taking them on an empty stomach to promote nutrient absorption, but many people get nauseated or constipated when taking prenatal vitamins.

You might have to experiment with what time of day makes you feel less icky, and if you have to take it with a snack (or pint of ice cream) — you do you, mama.

Fat-soluble

Taking fat-soluble vitamins (vitamins A, D, E, and K) with a meal that contains fat or oil will help them dissolve into your body. Your body will store any excess for later use, so you don’t need to take them every day. That’s great, right?

It depends. This also means that it’s easier to build up a toxic level by over-supplementing — so be cautious with these. Talk to your doctor for advice on what dose is right for you.

Try to get fat-soluble vitamins from a well-balanced diet whenever you can — think cheese, leafy greens, beef liver (if that’s your thing) and sweet potatoes are all excellent sources.

If you have to supplement because of a deficiency, just remember that small amounts will go a long way.

Water-soluble

Unlike fat-soluble vitamins, your body doesn’t store excess water-soluble vitamins. It takes what it needs for the day and anything left over gets flushed out (and down the toilet). That means you need to get enough of these vitamins every single day.

Water-soluble vitamins include the vitamin B group (all eight of them, including folate) and vitamin C.

A healthy, balanced diet should give you enough water-soluble vitamins, but there are exceptions, like for smokers and folks with severe dietary restrictions. Also, if you’re pregnant, supplementing your regular folic acid intake is an important way to support your growing baby’s health.

Best time to take B vitamins

Some believe best time to take B vitamins is in the morning because they play a direct role in how your body processes food into energy. More research is needed, but taking B-complex vitamins early could help ramp up that energy-making process throughout the day.

While it’s important to make sure you’re getting the recommended amount of nutrients, vitamin supplements aren’t right for everyone. There can be risks associated with taking vitamin supplements like:

  • Interactions. Be aware of any conflict between supplements and prescription medication (like antibiotics or thyroid meds).
  • Toxicity. Taking too much of any vitamin can be bad for you. FYI: fat-soluble vitamins have a greater risk of reaching toxic levels than water-soluble vitamins.
  • Birth defects. You shouldn’t double up on supplements, but this can be especially dangerous if you’re pregnant.
  • Quality isn’t guaranteed. Since supplements aren’t regulated the same as prescriptions or even over the counter (OTC) meds, make sure to source quality supplements.

The best time to take vitamins depends on the type. Try to take fat-soluble vitamins with a meal that contains some fat or oil to help them absorb into your body.

Some suggest taking multivitamins (including prenatal vitamins) and water-soluble vitamins in the morning before food or with a light snack, but there isn’t much research behind this.

Overall, your body is going to absorb vitamins differently. So, if your body starts talking to you — listen.