One problem that may result from following a Paleo diet is a hard time getting enough calories. For somone who is overweight this isn’t necessarily a bad problem to have, but what about for the person trying to maintain or gain weight?
The Paleo diet recommends lean meat, fruits, and vegetables, with nuts and oils in limited calories. But it can be hard to eat enough calories each day through only lean meat, fruit, vegetables – these foods have a low energy density and only so much of these foods can be consumed.
In the recent Paleo diet study, the subjects consumed around 1,350 calories per day, even though they were allowed to eat as much lean meat, fruit, and vegetables as they wanted. So how is a normal-weight active person or a person trying to gain weight supposed to get by on so few calories?
Also, male hunter-gatherers had a daily energy expenditure of around 3,000 calories. And from a meal perspective, these hunter-gatherers probably ate only 1 or 2 meals per day. From these two premises, you would have to conclude that their meals contained foods with high energy density, not just low energy-density fruit, vegetables, and lean meat.
I have been rereading one Loren Cordain’s papers on fat consumption by hunter-gatherers (#13). This paper analyzes what energy-dense foods were most likely consumed by hunter-gatherers. The analysis concludes that fat in organ tissue and bone marrow from wild game was most likely key in the development of homo sapiens.
Of course, no one eats organ tissue or bone marrow nowadays. But the idea is to find modern substitutes to try and duplicate the properties of these unique fats. Cordain recommends flax oil and canola oil. He also recommends fish oil (I think) and omega-3 eggs in limited amounts.
Personally, I have been leaning more towards eggs as the best substitute. Even though eggs may have been in limited supply during human evolution, at least they are an animal food, whereas canola and flax oils are both plant-based.
There are other clues around that fat was the real payoff for hunter-gatherers. Higher fat intakes are connected with higher testosterone levels. And I have found a few other things that I will be posting about soon.