If I drink tea with my meal, will it keep me from absorbing iron?

If I put spinach in my smoothie, am I canceling out the calcium?

Could a high-fiber diet lead to mineral deficiencies?

I get a lot of questions like these from listeners.

And while it's true that a number of factors can block the absorption of important minerals,

there are other factors that boost absorption. Not only that, but there are some buffers

built into the system.

Hello, I'm Monica Reinagle, and you're listening to The Nutrition Diva podcast, a show where we take a

closer look at the latest nutrition news, trends, and research, and answer your food and nutrition

questions. And today, I want to devote an episode to a whole category of questions revolving around mineral absorption

and what might be getting in the way. Questions like, does the fiber in my cereal

prevent me from absorbing the calcium in the milk? Does the exhalic acid and spinach prevent

me from absorbing the calcium in my smoothie? Could drinking

tea or coffee cause iron deficiency? Or one that I get quite often. Is calcium-fortified orange juice

or soy milk really any better than just taking a calcium supplement? And those are just the

breakfast questions. Each of these questions is perfectly

valid. The absorption of calcium, iron, and other minerals absolutely varies depending on the

specific foods that they're found in or that they are eaten with. Sometimes compounds in foods can bind to minerals and reduce how much your

body is able to absorb. The minerals themselves may be competing with one another for absorption

under certain conditions. For example, spinach contains a fair amount of calcium, but it also contains oxalids.

These are compounds that bind to the calcium and really prevent much of it from being absorbed.

That effect can spill over to calcium in other foods as well.

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