During the Pleistocene period, our early ancestors spent the majority of their metabolic resources digesting plant matter. All of that roughage required a lot of energy to break down. But it offered very little in the way of calories, protein or fat.

The result: Our vegetarian primate ancestors had larger digestive system... and a much smaller brain (roughly the size of an apple).

Then something amazing happened. These early hominids were not yet advanced enough to construct tools and hunt. But by watching animals like vultures pick apart a carcass and crack into bones, they learned to scavenge and retrieve the calorie-dense sources of fat and protein found in marrow and organs.

Because these native fats and proteins took less effort to digest and provided exponentially more nutrients , their metabolic resources could be allocated to more important things... like building a bigger and more powerful brain.

Consider this: A three-ounce serving of bone barrow contains nearly 500 calories, around 7 grams of protein and over 50 grams of fat (most of which is monounsaturated). And that's not all - it is also a smorgasbord of fat-soluble nutrients (including vitamins A, E, K and D) that fuel the heart, protect cells and boost the immune system.

In fact, bone marrow plays a very special role in immune health, thanks to its rich concentration of alkylglycerols. These unique, fat-like compounds have been used medicinally for centuries. They are known to boost the production of immune cells, red blood cells, and platelets. They are also found in breast milk and have been shown to boost antibody levels in nursing young.

My next Post will give you a recipe for Roasted Beef Bone Marrow.