Does Calc really interfere with Zinc absorbtion?

1Fast400 Forums > Supplements



Posted by: KP55 Jan 13 2005, 12:21 PM
I recently went to Kroger and they had a sale on some of these pills from Nature's Best, 2 for $8. The pills had Zinc and Magnesium and since money is a little tight and I ran out of ZMA recently, I bought them. Well when I got home I realized that they also have Calcium in them, and several times I've heard people say that Calsium interferes with ZMA absorbtion. However, since I had already bought them I tried them, and for the past 3 nights, I've gotten just as good if not better results than with ZMA. More deep sleep, wake up feeling refreshed, you know all the good things that ZMA gives us. However I was wondering then, if this works and I'm feeling like I've been taking ZMA, then does that really mean Calcium interferes at all? My g/f had an idea that maybe sinec the Calcium was in the pill form and not in a liquid from something like milk, then it might make a difference, but even that I don't really know about. Anyway just had a curious question, thought I'd see if someone could clarify, thanks


Posted by: Slayer of Souls Jan 13 2005, 04:03 PM
If you ingest Calcium and Zinc and Iron the body will prioritize the calcium over the other two. That is why sports nutritionists and most smart supplement companies advise athletes to take Iron and Zinc at a time when there is little or no calcium in the stomach. This goes for the Zinc containing supplement ZMA as well.

All that I can come up with.


Posted by: juggernaut333 Jan 13 2005, 05:27 PM
Yes,Ive read more than once that calcium and magnesium will interfere with each other...enough to make me wonder why so many companies offer a cal/mag combo.I would imagine you would still get benefit,but it may be ideal to take them separately and spaced out.That is not fact though...just my thoughts.I usually add my calcium citrate powder to my shake in the morning too help with lactic acid build up during my workouts as well as muscle excitability(and of course my bones!),then take my mag at night to help me sleep.

Posted by: jehry Jan 13 2005, 05:30 PM
Calcium actually blocks the absorption of many vitamins and minerals.

Zinc is one of those.

It might not block it totally, so you could still be getting partial absorption.

Also, make sure that the magnesium you got was magnesium aspertate (sp?). THat's the one you want.

Posted by: shpongled Jan 16 2005, 07:29 AM
The short answer is, you really don't have to worry about this all that much. Your body is designed to utilize what you give it.

"It appears unlikely that calcium per se has a negative effect on zinc absorption. We added calcium to cow’s milk formula to a level of ~1300 mg/L and found no significant difference in zinc absorption from the formula with the regular level of calcium (500 mg/L) through the use of radioisotopes in human adults and paired observations (Lönnerdal et al. 1984 ). Similarly, Spencer et al. (1984) and Dawson-Hughes et al. (1986) added large amounts of calcium to a meal and found no effect on zinc absorption in human adults. It also appears that the long-term use of calcium supplements has no effect on zinc status; Gambian women who were given 1000 mg calcium/d had plasma zinc concentrations similar to those of unsupplemented women (Yan et al. 1996 )."

From: http://www.nutrition.org/cgi/content/full/130/5/1378S

Posted by: Aeternitatis Jan 16 2005, 02:49 PM
QUOTE (shpongled @ Jan 16 2005, 07:29 AM)
The short answer is, you really don't have to worry about this all that much. Your body is designed to utilize what you give it.

I've always believed in something like this. I mean, I would think the body is smart enough to get by without us being aware of what micronutrients we are eating at what times. I have always assumed that there were built in checks and balances and we needn't be conerned with isolating certain things such as Zinc from calcium.

Posted by: shpongled Jan 16 2005, 05:46 PM
QUOTE (Aeternitatis @ Jan 16 2005, 11:49 AM)
QUOTE (shpongled @ Jan 16 2005, 07:29 AM)
The short answer is, you really don't have to worry about this all that much. Your body is designed to utilize what you give it.

I've always believed in something like this. I mean, I would think the body is smart enough to get by without us being aware of what micronutrients we are eating at what times. I have always assumed that there were built in checks and balances and we needn't be conerned with isolating certain things such as Zinc from calcium.

Well, there are some cases where it works like this, but not many. The main issue is some compounds in food, particularly non-animal foods, that can inhibit mineral absorption.

Posted by: Aeternitatis Jan 16 2005, 06:53 PM
Which is exactly why I hate soy.