T Nation

When to Take ZMA and Calcium Effects

there’s general info out there that zinc and calcium together will reduce absorption since magnesium would bind to calcium and nullify the absorption of the element.

people take ZMA at night for better sleep.
people also take a last-day meal of casein (or cottage cheese usually) which is pretty high in calcium.
thus, there’s a problem here in nutrient timing and absorption.

also, calcium needs magnesium for absorption. so you see my dilemma here, what info and conclusion should i trust and make?

of course this all could be overthinking, but if i am going through the effort of getting ZMA and taking it, i’d like to maximize its benefits

Great question, I’ve often wondered the same thing.

I try and have my final protein shake of the day about an hour before I take my ZMA.

A lot of experts have said that the timing doesn’t really matter, but it’s easy enough to take your ZMA 30 to 60 minutes prior to your pre-bed meal if you are concerned.

it only takes 30-60mins to get absorb the minerals?

I cannot recall where I found it, but I distinctly rememver reading at least 30 minutes before or after any calcium.

I do this with a lot of regularity and always sleep and wake up feeling great.

I take ZMA approximately 60 minutes before I go to bed. Right before bed I have my last meal. I have been doing this for several years.


Before going to bed I would always have some yogurt and walnuts, casein in milk, fish oil, and ZMA, so lots of calcium there… I had also wondered the same exact thing, since I had heard that calcium interferes with absorption. (In fact, it is written right on the bottle). I’m not sure if this was optimal, but it seemed to work fine for me.

If you’re looking to “optimize” you might want to try taking the ZMA a little bit earlier. The bottle of ZMA I have suggests that taking it on an empty stomach is more effective.

Alternately, you could simply just try doing things one way for a couple of weeks, and then change it and observe the effects. This seems like the most logical idea.

Like others have said, take ZMA about an hour pre-bed or before pre-bed meal. It shouldn’t take long for the minerals to absorb depending on how full your stomach is. This is what I use to do.

-60 minutes later, Metabolic Drive with peanut butter (for example)
-70 minutes later (10 mins after shake), sleep.

thanks guys

Good post.

I used ZMA for my contest prep – I generally have CC with PB a couple hours before bed and take ZMA thirty minutes before bed.

Excerpt from a book I read a long time ago; for those too bothered to read it, a summary.

Calcium, Magnesium, Iron, and Zinc are collectively known as ‘Bivalent Minerals’; they are all absorbed at the same spot in the intestinal tract.
The reason to avoid taking these at the same time is because they compete for absorption, this isn’t really a problem with zinc and magnesium (as in ZMA) since they are both needed in fairly low quantities (15mg for zinc is the RDI and magnesium is about 400mg) However, calcium is needed in such large quantities (for athletes, like 2g a day) that if taken at the same time, calcium gets absorption priority since it is in abundance (If there’s 30mg zinc, as in a ZMA product, and 400mg calcium, which is an estimate for a scoop of casein, then there’s pretty much a 7% chance that a particle absorbed would be zinc, rather than calcium (assuming no magnesium or iron), and this is exasperated when the magnesium is also factored in regarding ZMA)