Assistant Beauty & Health Editor
Assistant Beauty & Health Editor
Hannah Frye is the Assistant Beauty Editor at mindbodygreen. She has a B.S. in journalism and a minor in women’s, gender, and queer studies from California Polytechnic State University, San Luis Obispo. Hannah has written across lifestyle sections including health, wellness, sustainability, personal development, and more.
Expert review by
mbg Nutrition Research Scientist
Emma Engler, M.S., is a Nutrition Research Scientist at mindbodygreen supporting nutrition product research, development, and innovation, as well as science education and communications.
Image by Tatjana Zlatkovic / Stocksy
February 28, 2024
Stomach aches, nausea, and fatigue are a few of the side effects you might feel after taking your vitamins. However, taking your supplements at the right time of day or night can help combat these side effects for good.
We know that it can be confusing to decide when to take certain vitamins (there are lots of different kinds out there, after all), so we made it easier with this cheat sheet. Here’s the best time to take every vitamin in your daily regimen.
The need-to-knows:
- B vitamins shouldn’t be taken at night. Since they tend to be more energizing for some individuals, they may cause sleep trouble in some people. While this isn’t the case for everyone, other supplements like magnesium and CBD are more suitable for bedtime.
- Fat-soluble vitamins should be taken with food. This includes vitamins A, D, E and K. Taking these with meals will encourage proper absorption into the body.
- Vitamins, minerals, and other active ingredients can have medication interactions, such as interfering with absorption, so ask your physician about how to time yours with your other prescriptions to be safe.
What time to take vitamins & supplements
Below you’ll find a breakdown of the most important instructions for taking each of the popular vitamins. We’ll let you know if it should be taken with or without food, what time of day is best, and any common contraindications to keep in mind.
Vitamin A: Anytime, with food
“Vitamin A is a fat-soluble vitamin. Like all fat-soluble vitamins (A, D, E, and K), its bioavailability increases when they are taken with a source of fat,” explains registered dietician Maya Feller, R.D., CDN.
Either take your vitamin A with a full meal containing healthy fats or make a snack with ingredients like avocado, peanut butter, etc. to ensure it’s absorbed properly.
Feller adds that people who are pregnant or have liver disease will want to talk to their doctor before starting vitamin A (especially in the retinol form) supplementation. Some blood thinner medications can also have contraindications with high doses of vitamin A, she says, so flag those to your doctor if you’re on them too.
Vitamin C: Anytime, with or without food
“Vitamin C is a water-soluble vitamin and does not need to be taken with food to increase bioavailability,” Feller says.
However, when taken in excess, some people experience GI symptoms including upset stomach and loose stools when taking vitamin C, so keep that in mind if you’re trying a new product.
Anyone who is prone to specific types of kidney stones will want to talk to their doctor first.
Vitamin D: Anytime, with food
Vitamin D’s bioavailability increases when you take it with a meal that contains fat, Feller says. However, the time of day doesn’t matter as much.
Vitamin E: Anytime, with food
Vitamin E is another fat-soluble vitamin that should be taken with a meal that contains healthy fats to increase absorption.
Similar to vitamin A, those on blood thinner medications will want to talk to their doctor about when and if to take this one.
Vitamin K: Anytime, with food
Vitamin K is a fat-soluble vitamin that’s best taken with food.
Lifestyle physician and longevity expert Poonam Desai, M.D. suggests that people with kidney health concerns talk to their doctor about when and if to take this vitamin.
B vitamins: In the morning, with or without food
“B vitamins are water soluble, so [they] can be taken on an empty stomach any time of the day,” Desai says.
However, she adds that some people do report difficulty sleeping after taking some B vitamins, so she recommends taking them in the morning to be safe.
“In addition, B vitamins play a vital role in metabolism and energy production—another reason morning is a good time to take them,” she notes.
Multivitamin: In the morning, with food
Because most multivitamins contain B vitamins, Desai recommends taking them in the morning to avoid sleep disruptions.
Since multivitamins also usually include some or all of the fat-soluble vitamins (A, D, E, and K), you’ll want to take them with food as well.
Prenatal vitamin: Anytime, with food
For optimal absorption, Desai recommends taking prenatal vitamins with food. “Many women experience nausea during pregnancy, and taking a prenatal vitamin with food lowers the chance of nausea, acid reflux, and upset stomach,” she adds.
If your prenatal contains B vitamins, it’s best to take it in the morning.
When to take other supplements
Now that we’ve covered the best time to take vitamins, let’s dig into when to take other popular supplements, like minerals and probiotics:
Iron: Anytime, with food
“Iron is a mineral that can be taken with a source of vitamin C to increase its absorption,” Feller says. Iron vitamins can be taken on an empty stomach, but its best to take with food.
This mineral can cause stomach discomfort in those prone to GI concerns, she says. If this happens to you, consider pairing your supplement with food (but avoid high doses of calcium, fiber-rich foods, or taking alongside thyroid medications to prevent possible interactions).
Constipation is also a possible side effect of iron supplementation. If you have trouble getting things moving after taking iron, Feller recommends switching to a liquid iron supplement that’s easier to digest.
Magnesium: It depends on the type
- Magnesium bisglycinate: Magnesium bisglycinate has specific benefits for sleep quality, so it should be taken an hour or so before bed. This form tends to be the most bioavailable and easy on digestion and does not need to be taken with food.
- Magnesium citrate: Best taken earlier in the day with some food.
- Magnesium oxide: Best taken earlier in the day with some food.
- Magnesium malate: Best taken first thing in the morning with some food.
Feller points out that those with heart, kidney, or gastrointestinal considerations and those on prescription medications should check with their doctor before starting a high dose magnesium supplement.
Calcium: Anytime, with food
Calcium is another nuanced supplement when it comes to its relationship with other medications (particularly thyroid medicine), so make sure to check with your physician before buying it and consider the optimal time of day to supplement to avoid absorption barriers or side effects.
Another note is that calcium absorption is limited to approximately 500 mg at a time so it’s best to space out taking calcium supplements across the day if you’re consuming higher doses (e.g., for bone density needs).
Probiotics: Anytime, with or without food
Different probiotics contain different types of bacterial strains, so their effects vary greatly. For this reason, Feller explains that there is no universal recommendation for when to take probiotic supplements. Look to the label to see whether or not yours should be taken with food, in the morning, etc.
Protein powder: Anytime, preferably soon before or after a workout
As for timing, that really depends on your goal and daily schedule. If you plan on working out that day, consider taking protein within a few hours before or after your workout.
If you aren’t exercising that day but still want to take protein powder (a worthy stepping stone to reaching your daily protein intake goals), just take it whenever you want a snack or add it to your meal.
Collagen: Anytime, with food
The protocol for collagen greatly varies depending on the forms included in your supplement, Desai says. However, most of them should be taken with food to increase absorption, she notes. Given that many collagen supplements come in powder form, it’s easy to work them into smoothies, lattes, yogurt, etc.
Hemp-derived CBD: Anytime you want to relax, with or without food
Considering hemp-derived CBD has a calming effect, it’s particularly beneficial to take before bed or when you want to feel relaxed.
This supplement doesn’t come with quite as many contraindications, but it’s always best to consult your physician before adding CBD into your regimen.
| Supplement | When to take | With food |
|---|---|---|
| Vitamin A | Anytime | Yes |
| Vitamin C | Anytime | Doesn’t matter |
| Vitamin D | Anytime | Yes |
| Vitamin E | Anytime | Yes |
| Vitamin K | Anytime | Yes |
| B Vitamins | Morning | Doesn’t matter |
| Multivitamins | Morning | Yes |
| Prenatal vitamins | Anytime | Yes |
| Iron | Anytime | Yes |
| Magnesium | Depends on form | Depends on form |
| Calcium | Anytime | Yes |
| Probiotics | Anytime | Depends on strain |
| Protein powder | Anytime | Doesn’t matter |
| Collagen | Anytime | Yes |
| CBD | Anytime you want to relax | Yes |
The mindbodygreen POV
Some vitamins and minerals work best when taken in the morning, while others are well-suited for nighttime. You’ll also want to take certain supplements with food in order to increase their bioavailability (and decrease your risk of digestive upset).
Also, remember to double-check your supplement routine to ensure you’re not consuming more than the recommended dose, as many vitamins and minerals have a tolerable upper limit (UL) or max daily intake that has been demonstrated to be safe.
This guide provides a general primer on when to take your vitamins and supplements, but refer to the label on your particular product to know for sure.
Finally, consult your doctor before investing in supplements if you’re on medication and let them know if you have any unwanted side effects like GI issues, nausea, and so on.
FAQ
Is it better to take vitamins in the morning or at night?
B vitamins have been shown to disrupt sleep in some individuals and thus are best taken in the morning. Vitamins A, C, D, E, and K can be taken any time of day—but most of them should be consumed with food.
What vitamins are best taken at night?
Supplements like magnesium and CBD can support sleep when taken before bed.
Should you take vitamins before or after eating?
It depends on the supplement. It’s best to take fat-soluble vitamins like vitamins A, D, E, K, and B right after or with a meal to increase absorption.
The takeaway
Knowing when to take your supplements can help you maximize their benefits. While there are helpful guidelines, it’s still best to double-check your product label and ask your physician if you’re unsure. Not sure what vitamins you should be taking in the first place? Take our quiz for a personalized supplement routine that will help you optimize your well-being.
