Does dairy affect iron absorption?

Last updated 17/01/2024

If you look up dairy and iron absorption online, you'll be met with a tonne of resources that tell you to avoid consuming dairy foods with iron rich foods.

Dairy foods contain nutrients like calcium, casein and phosphate that (theoretically) compete with iron at absorption sites in the gut.¹ This is what's known as a 'mechanistic' relationship, meaning we base our understanding on the relationship between these nutrients based on the mechanisms of digestion we know happen in our gut.

Real world studies (also known as in vivo studies) test what happens in real life conditions. One in vivo study showed the reduction in iron absorption from one meal with the addition of dairy foods was 0.2% lower or less.² This shows that in real life conditions, consuming dairy foods has no significant effect on iron absorption. The nutritional benefits of dairy foods likely outweigh the slight inhibitory effect they may have on iron availability.

If you are worried about your iron levels, its a good idea to get a blood test from your GP. If your iron levels are within normal levels, there's no need to be too concerned about the types and combinations of foods you're eating. If you have an iron deficiency however, it's a good idea to get specialised advice from a dietitian about ways to get more iron in your diet. They'll also have advice on how to organise your diet to improve your iron absorption.