You may be eating nutrient dense food but how much of those nutrients are you actually absorbing? This is what is meant by bio-availability; it’s how much of a certain nutrient from food is actually taken in and used in the body. We absorb fewer nutrients from the food we eat than is actually contained in it.
Some foods are more bio-available to the human body than others, we absorb nutrients from animal based foods easily, and a good step to nourish the body is not only to eat nutrient dense food but also these bio-available foods.
This table ranks food according to their nutrient density and bio-availability.
Table sourced from www.chriskresser.com
You can see from this table that the highest nutrient foods come from real food, the foundation of a Primal diet. The lowest nutrient foods are all the ones we try avoid and these foods are also the ones that promote weight gain, craving and inflammation.
You will also notice that that plant and animal fats are not particularly nutrient dense, however they do play and important role as they help us to absorb other nutrients from other foods.
On the opposite side of the coin are the whole grains and legumes. Not only do they lack any real nutrition they actually contain nutrient inhibitors that slow down and stop the nutrients we do want. A quick note on the nuts and seeds, they do contain some of the anti-nutrients but by soaking them first you can limit the effect.
So the take home from this, you want to eat the most nutrient dense food you can but also consider how bio-available those nutrients are. By putting whole foods on the top of the list and sugar and refined grains at the bottom (Or not even on it) you will be giving yourself a better chance of getting all the nutrients you need.