
Answer:
The question of when to take vitamins together or separately is an excellent one and which we address in the "What to Consider When Using" and "Concerns and Cautions" sections of our Product Reviews of vitamin or mineral supplements. How you take a supplement can be just as important as which product you take -- both may impact how much of a nutrient your body actually gets.
A few rules of thumb on how to take vitamins and minerals:
- If you take a large dose of a mineral, it will compete with other minerals to reduce their absorption. The mineral most often taken in large amounts is calcium: The dose is usually several hundred milligrams, compared to doses of just a few milligrams or even microgram amounts (1,000 micrograms = 1 milligram) of most other minerals. So if you take several hundred milligrams of calcium from a supplement, take it at a different time of day than other mineral supplements or a multivitamin/multimineral supplement. Doses of magnesium can also be relatively large and should, ideally, be taken apart from other minerals. If you take high doses of zinc long-term (50 mg or more per day for 10 weeks or longer ), be aware that it can cause copper deficiency, so you may need to supplement with copper as well.
- High doses of calcium or other minerals (including magnesium, certain forms of iron, and zinc) from supplements may decrease the absorption of carotenoids, such as beta-carotene, lycopene and astaxanthin, from foods and/or supplements. It is best to take carotenoid supplements at a different time of day than a supplement or meal containing large amounts of a mineral (e.g., hundreds of milligrams of calcium or magnesium).
- Some vitamins can actually enhance the absorption of other nutrients. Getting an adequate amount of vitamin C from your diet or supplements, for example, can enhance iron absorption from supplements and plant foods, but vitamin C and iron do not need be taken together.
- The fat-soluble vitamins (A, D, E, and K) are likely to be better-absorbed if taken with a meal that contains fats, as this triggers the release of bile into the intestine, which aids fat absorption. In fact, one study found that taking vitamin D with the largest meal of the day – typically dinner -- rather than breakfast increased blood levels of vitamin D by about 50%. If you take a fish oil supplement along with fat-soluble vitamins, this may help a little, but not by much -- the amount of fat in a fish oil capsule is only about 1 gram, while studies have shown maximal bile release with at least 6.5 grams of fat (Marciani, Eur J Clin Nutr 2013). Other supplements that have improved absorption when taken with fats include astaxanthin, boswellia, CoQ10, curcumin/turmeric, and quercetin, many of which are also available in special formulations to further improve absorption.
Similarly, the absorption of carotenoids and fat-soluble vitamins from raw vegetables is increased when the vegetables are consumed with a fat such as the oil in salad dressing or foods such as avocado. Sign in as a member to learn the amount of dressing that seems to be beneficial for increasing absorption of vitamins from raw vegetables. - It may be best to take fat-soluble vitamins apart from one another, as evidence (mainly from animal and cell studies) suggests that moderate to large doses of fat-soluble vitamins reduce absorption of other fat-soluble vitamins - by about 10 to 50% - due to competition. Absorption of vitamin K appears to be particularly reduced by other fat-soluble vitamins, while vitamin A absorption is least affected and may actually be better absorbed when taken with vitamin E (Goncalves, Food Chem 2015). Taking vitamins D, E, or K several hours before or after other fat-soluble vitamins would seem to maximize their absorption.
- Taking certain supplements with food can reduce gastrointestinal side-effects. For example, taking magnesium with food can reduce the occurrence of diarrhea, and taking iron with food can reduce the chance of stomach upset.
- Be aware that vitamins and minerals can also affect the absorption and effectiveness of medications. You'll find more specific information about this in the "Concerns and Cautions" section of each of our Product Reviews.
- Multivitamin/multimineral supplements contain many nutrients that, as described above, can potentially interfere with the absorption of each other. Keep in mind that, at moderate doses, the reductions in absorption are only partial -- probably not exceeding, at most, a 50% reduction and, more often, even smaller -- so you will still get most of what you would normally have absorbed if the nutrient was taken alone. Unless you are known to be deficient in a particular nutrient, this reduction may not be clinically important. However, if you are deficient in a nutrient, it may be best to take that nutrient separately, as described above. If you need to get more iron, magnesium, or zinc, for example, it may be best to choose a multivitamin that does not contain more than 200 mg of calcium. (The results table in our Multivitamin Review allows for easy comparisons of nutrient amounts among products.)
Because how and when you take supplements can affect absorption, the table below condenses the information listed and outlines how to maximize absorption of certain vitamins, minerals, and carotenoids.
How to Best Take Vitamins, Minerals, and Carotenoids
Take with food? | Notes to maximize absorption* | |
Vitamins: | ||
A, D, E, & K | Yes, with largest meal of the day containing oils or fats | Don’t take vitamin K with large doses of vitamin E. |
B-12 | Can be taken with or without food. | Doses of more than 1.5 mcg should be divided and taken at least 6 hours apart. To get the most B-12 from a meal and supplement, take them at different times of day. |
B-6 | Preferably with food | |
Folate | May be best to take on an empty stomach | Folic acid is absorbed about 1.7 times as well as natural folate, and twice as well if taken on an empty stomach. |
C | Yes, with a meal if causing stomach upset | Divide large doses over course of the day |
Minerals: | ||
Calcium and magnesium | Yes, to improve absorption and to reduce the possibility of diarrhea from magnesium | Don’t take together in large amounts (hundreds of milligrams). Don’t take more than 500 mg of calcium at once. |
Iron | Best not to take with food — and definitely not with tea or coffee. But can take after a meal if needed to reduce stomach upset. | Don’t take with large amounts of other minerals. Taking with orange juice appears better than taking with water. Getting adequate C may enhance absorption, but taking with a vitamin C supplement doesn’t help. |
Zinc | Can be taken with or without food. | Don’t take with milk, calcium, or high-fiber foods. If taken as lozenge for colds, allow to dissolve — don’t chew. |
Carotenoids: | ||
Beta-carotene (vitamin A), lycopene, zeaxanthin, lutein | Yes, with a meal that contains oils or fats | Don’t take with minerals or meals high in calcium or magnesium |
*To avoid taking things together, take at least two hours apart.
Additionally, keep in mind that these issues are not of significant concern when consuming a multivitamin providing up to the recommended daily intakes (RDAs) of vitamins and minerals -- as long as it does not contain more than 250 mg of either calcium or magnesium.
There does not appear to be any evidence that taking probiotic supplements at the same time as vitamin or mineral supplements interferes with the absorption or potential benefits of vitamins, minerals, or probiotics, but be aware that you may want to avoid taking a calcium supplement at the same time as consuming probiotic dairy foods such as yogurt or kefir, if they already provide a significant amount of calcium, as you can only absorb about 500 mg of calcium at a time.
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Cory F
March 08, 2024“Similarly, the absorption of carotenoids and fat-soluble vitamins from raw vegetables is increased when the vegetables are consumed with a fat such as the oil in salad dressing…absorption of fat-soluble vitamins and carotenoids from raw vegetables is likely to be increased if consumed with low-fat (~4 grams per serving) or standard (~8 grams per serving) oil dressings…”
What about the fats in creamy, non-oil salad dressings like Thousand Island?
Great question! We've added information to answer it in the following section of our article above: https://www.consumerlab.com/answers/which-vitamins-and-minerals-should-be-taken-together-or-separately/how-to-take-vitamins/#creamy-dressing-dips-fattyfood
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Carmella172
February 06, 2023Is it true that you should take your vitamins at least 6 hours after taking synthroid and calcium is best absorbed if you take it twice a day.
Hi Carmella, it's true that some supplements should be taken several hours apart from Synthroid. It's best to take calcium, for example, at least four hours after taking Synthroid, or possibly longer, if taking a high dose of calcium. Only about 500 mg of calcium can be absorbed at a time, so, if taking more than 500 mg, it is best to divide the dose. See our article about supplements and levothyroxine (Synthroid) https://www.consumerlab.com/answers/do-any-supplements-interfere-with-thyroid-hormones/hypothyroidism-and-supplements/ as well as the ConsumerTips section of our Calcium Supplements Review for details https://www.consumerlab.com/reviews/bone-supplements-calcium-with-vitamin-d-k-magnesium/calcium/#howtotake.
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Gary169
February 06, 2023It appears a PB&J sandwich + vitamin, mineral, and carotenoid supplements are a good combination
Yes, as peanut butter provides fats/oils that would aid in the absorption of fat-soluble vitamins.
sls1964
February 12, 2023haha. love it!
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Thank you, glad to hear you're finding it helpful!
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Heather166
February 05, 2023This table is a great idea! Very helpful!
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Carol Ann161
February 05, 2023According to that best time to take supplements table, does this mean people taking MULTIVITAMINS are taking it for nothing, because it’s components will not be absorbed correctly?
Hi Carol, we've added information about this in our article above https://www.consumerlab.com/answers/which-vitamins-and-minerals-should-be-taken-together-or-separately/how-to-take-vitamins/#multivitamins.
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Cheryl157
February 04, 2023What is the optimal amount of fat to consume in order to facilitate absorption of fat soluble vitamins?
Hi Cheryl, this is explained in the paragraph about fat-soluble vitamins in the answer above https://www.consumerlab.com/answers/which-vitamins-and-minerals-should-be-taken-together-or-separately/how-to-take-vitamins/#fatsoluble.
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Yes, fiber can affect the absorption of medications as well as vitamins and minerals, although typical doses of fiber have not generally been found to affect blood levels of minerals -- see the Concerns and Cautions section of our Fiber Supplements Review for details https://www.consumerlab.com/reviews/psyllium-supplements/psyllium/#cautions.
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Larry153
February 03, 2023I take fiber (Metamucil) twice a day. Does that have any impact on supplement absorption?
Barbara154
February 25, 2023Fiber goes through the digestive system without getting digested or absorbed. If there's lots of fiber and medication in the intestine at the same time, it's possible that the medications or supplements you take may get swept along with the fiber, so it will be excreted instead of fully absorbed.
So, just to be on the safe side, it might be prudent to take your medications two to three hours before or after your fiber supplement.
Hi Barbara, it is generally recommended that medications be taken at least one hour before or four hours after taking a fiber supplement containing psyllium, but it's best to consult your physician before using psyllium if you are taking medication. See the Concerns and Cautions section of our Psyllium Fiber Supplements Review https://www.consumerlab.com/reviews/psyllium-supplements/psyllium/#cautions.
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Tracy3333
July 26, 2022i love these articles that tell you how to take the supplement, so many don't help you navigate this
Researcher
February 21, 2023I love these articles also! But sure seems to be alot of work to stay healthy now. I have a notebook with indexes and updates on my supplements!
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Walt142
April 03, 2022Is it OK to take acetaminophen and vitamin c?
Please see our CL Answer about supplement interactions with acetaminophen, which includes information about vitamin C https://www.consumerlab.com/answers/which-supplements-should-be-avoided-when-taking-acetaminophen/acetaminophen-supplement-interactions/.
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Dr Melissa
March 05, 2022Hi, how far apart should we separate zinc from calcium? And how far apart should we separate zinc from magnesium? Thanks
Please see the ConsumerTips section of the Calcium Supplements Review for information about this https://www.consumerlab.com/reviews/bone-supplements-calcium-with-vitamin-d-k-magnesium/calcium/#otherminerals.
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Dawn138
December 21, 2021So the advice is to take mineral supplements separately from each other, and same goes for high dose fat soluble vitamins. What about taking a mineral supplement with a vitamin, like magnesium with D? Any problems there?
Hi Dawn, please see our response to this question below https://www.consumerlab.com/answers/which-vitamins-and-minerals-should-be-taken-together-or-separately/how-to-take-vitamins/#comment-18596.
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PATRICIA135
September 22, 2021Vitamin B-12 says to take with a meal. Does it matter if it is at breakfast instead of lunch or dinner?
It should not matter which meal. It is not fat soluble, so you don't need to take it with a meal high in fats, as with fat soluble vitamins.
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Karen128
October 30, 2019When it is recommended to take certain vitamins together, such as Vitamin D and Magnesium, does that mean at the same time or just on the same day?
Hi Karen - Adequate intake of magnesium helps maintain optimal levels of vitamin D, as discussed in our Vitamin D Review.
https://www.consumerlab.com/reviews/vitamin-d-supplements-review/vitamin-d/#magnesium. However this does not mean that the two need to be take together, or even that you need to supplement with either if you already get enough of them from your diet and, for vitamin D, sun exposure.
Karen131
November 04, 2019I understand but that doesn't answer my question. I don't know what "take together" means. Pretend I need to take 2 supplements and it is recommended to take them together. Does that mean at the same time or the same day?
Karen - It will depend on which supplements are to be taken. In this case, they would not have to be taken at the same time. In fact, you should take vitamin D with (or shortly before) a meal containing fats, while magnesium does not have to be taken with a meal.
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indeterminacy@msn.com
March 24, 2019does anyone know anything about CELL FOOD? by NuScience Corp. is it alright to take it and does it actually improve your memory?
Hi Karen - You can find information about the clinical evidence for CELLFOOD in this CL Answer: https://www.consumerlab.com/answers/does-cellfood-really-work/cellfood/.
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Ellen121
February 10, 2018Does the caution on calcium supplements apply to PLANT BASED calcium supplements as well?
Hi Ellen - Yes, this applies to plant-based calcium supplements as well. You can find more information about getting enough calcium, and the risks of taking too much supplemental cacium, in the "ConsumerTips" ( https://www.consumerlab.com/reviews/Bone_Supplements-Calcium_with_%20Vitamin_D_K_magnesium/calcium/#using) and "Concerns and Cautions" ( https://www.consumerlab.com/reviews/Bone_Supplements-Calcium_with_%20Vitamin_D_K_magnesium/calcium/#cautions) sections of the Calcium Supplements Review. Also see this CL Answer: https://www.consumerlab.com/answers/how-much-calcium-do-you-need-and-what-forms-are-best/calcium/
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Andrew119
February 21, 2017It is unclear to me if taking vitamin D3 and K2 together is problematic.
Hi Andrew - Please see this CL Answer https://www.consumerlab.com/answers/if-vitamin-k-absorption-is-reduced-by-other-fat-soluble-vitamins-like-vitamin-d-should-they-be-taken-separately/vitamin-k-vitamin-d-absorption/. Information can also be found in the "What to Consider When Buying" section of the Vitamin K Supplements Review: https://www.consumerlab.com/reviews/vitamin-k-supplements-review/vitamin-k/#buying
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OrganicGirl
December 07, 2016Suggesting people take Vitamin D in the evening with dinner for increased absorption is not good, it blocks melatonin production. Best to take Vitamin D with a high fat breakfast, which we should all have to lower blood sugar and insulin. I know you don't say take it with dinner, but you elude to a study where it was absorbed better at dinner, but that is NOT the best time to take it.
Hi Eileen - It's true that high doses vitamin D may decrease the production of melatonin. See the "Concerns and Cautions" section for more about this: https://www.consumerlab.com/reviews/vitamin-d-supplements-review/vitamin-d/#cautions. Please also see the section about insulin resistance and glucose control: https://www.consumerlab.com/reviews/vitamin-d-supplements-review/vitamin-d/#diabetes.
Melinda115
May 07, 2018I am 63 and having sleeping problems . I had been taking 5000 per day to up my levels but I suspect the D was the culprit so I have stopped taking it for awhile.
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Tim110
June 26, 2016Fish oil is a commonly used supplement. My supplement (Vitamin Shoppe) contains 1000 mg of fish oil concentrate, which has 300 mg EPA and 200 mg DHA. Will these amounts affect the absorption of Vit D and CoQ10(ubiquinol) which I take at the same time? Should I still try to have some fat in the meal before taking these?
Hi Tim - Please see this CL Answer: https://www.consumerlab.com/answers/is-it-best-to-take-fat-soluble-supplements-like-coq10-curcumin-and-vitamin-d-with-fats-to-increase-absorption/fat-soluble-vitamins-fish-oil/
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David104
December 16, 2015Your site should never use the term, "Vitamin K". You should revise the entire site to say "vitamins K1 and K2" or "Vitamin K1" or "Vitamin K2".
The reason is to promote education about K2 and to be clear.
Thanks
Hi David - Although our report is entitled Vitamin K Supplements, it provides extensive information about the differences between vitamins K1 and K2 and the many forms of K2, e.g., MK-4 and MK-7.
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OrganicGirl
July 12, 2015Vitamin D doses also pause the production of melatonin, so I would advise having your Vitamin D in an earlier meal than dinner if you have problems with insomnia.
Thank you Eileen. You can find information about this in our Vitamin D Supplements Review: https://www.consumerlab.com/reviews/vitamin-d-supplements-review/vitamin-d/#melatonin.
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S99
July 12, 2015That is very valuable information. Thank you.
I am a little confused about calcium and magnesium. I have always operated under the assumption that they are best taken together, along with vitamin D, as each of these aids in the absorption of the others. Is this incorrect?
Thank you!
Thank you for your question. We've now answered it, here: https://www.consumerlab.com/answers/how-much-calcium-do-you-need-and-what-forms-are-best/calcium/
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Jeannemarie93
July 12, 2015Taking "high doses" of zinc long term should be avoided b/c in addition to impairing copper status, it can actually dampen the immune system. You might be prescribed higher amounts of zinc following surgery, but that should generally be only about 2 weeks. So rather than adding a copper supplement, discontinue the zinc supplement or check with your doctor about the dose and duration.
You are correct, Jeannemarie. More about this is found in the Zinc Supplements Review: https://www.consumerlab.com/reviews/zinc-supplements-lozenges-review/zinc/#cautions
Twyla96
July 14, 2015what is considered a high dose of zinc?
Hi Twyla - We've now added this information to the answer above.
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