What Vitamins Can You Take Together?

Today's public service announcement.

You might already know that some vitamins should not be taken together.  But which ones?

Iron and calcium should not be taken together, unless it’s a very small amount of calcium.  300 mg of calcium or so will block the absorption of iron.  The reason some multis have both iron and calcium is because they often have only small amounts of calcium, maybe 200 mg.  That amount won’t block the absorption of iron but much more will.  Iron and calcium should be taken at least two hours apart.

If your multi has iron in it and you want to absorb that iron, do not take your multi with your calcium.  If your multi has no iron, it’s fine to take your multi with your calcium.

Take your iron with vitamin C for best absorption.  The ratio is 200 mg C to every 30 mg iron.  That’s 30 mg elemental iron, so if you take 325 mg ferrous sulfate, for example, you’re only getting 65 mg elemental iron, so you’d need 400 mg vitamin C (but carbonyl iron is absorbed better than ferrous sulfate).

Keep in mind that people can only absorb about 500 mg calcium at once, so divide your calcium into doses of about 500 mg and take them at least two hour apart.  Keep in mind that the ASMBS recommends 1500-2000 mg calcium citrate per day, so you need three or four separate doses.  And make sure you’re taking calcium citrate, not calcium carbonate.

B vitamins work together so it’s good to take your B’s at the same time.  Your multi has lots of B’s in it, so take it with your B12 if you use a sublingual B12.  If you take a B complex and/or biotin, take that at the same time.

If you take vitamin D3, it does not matter what you take it with.

Zinc and copper don’t work well with lots of other vitamins and minerals, so if you take those, it’s best to take them by themselves.

Kelly

 I never knew this. Thanks for the information. It was very helpful and probably will have me feeling better to change when I take my iron.

Hello Kelly,

Thanks for the information! What time of the day is it best to take iron?

It doesn't matter as long as it's at least two hours away from your calcium.  I like to do mine at bedtime because I know I won't want calcium after I go to bed so I only have to worry about it two hours before.  But whatever time works best for you is fine.

Thank you for posting this...this is some very helpful information. I was wondering about my calcium and multi, if it should be taken together.

If there is no iron in your multi, it's fine.  If there is iron in the mult but you take more iron later and don't care if you don't absorb the iron in your multi, it's still fine.  Calcium will prevent you from absorbing iron but iron will not keep you from absoring calcium.

My doctor only has me on a multivitamin and a B12 once a week.  Im taking 1000 mg of vitamin c on top of that.  I dont get calcium or iron until month 3. I wonder if this is to see where my numbers fall.

The ASMBS says to start iron as soon as you get home from the hospital and to start calcium no later than one month.  You might want to ask your doc why he disagrees with their guidelines.  I think waiting so long is a very bad idea.  Why would you want to see how low your numbers fall when you don't take the vitamins you need for three whole months?  I would personally rather see where they fall when I am taking the correct supplements.

Yeah the packet I received has such different information than what I read on this webiste.  Im just guessing they want to see numbers.  I have no idea why they want me to wait.  Im hoping that in my bariatric vitamins Im getting enough to get by until I see him and ask.  Im not going to question them, they are the best team in the US.

What makes you think they are the best team in the US?  Why are you afraid to even ask them questions about their recommendations?  If they are the best team in the U.S., don't you think they'd have some data to back up their recommendations?