Last updated: 19-Aug-15
Written by Sports Dietitian Rin Cobb
No longer a thing of the past, eating as our Palaeolithic ancestors once ate is the latest diet fad to hit our shelves. Its popularity is evident; go into any bookshop and you’ll find an array of Paleo diet books on sale, perhaps preferable to wading through the 2,617 downloads available for your Kindle. So what is a Paleo diet and what does it mean for runners?
Diet of our Ancestors?
For those conjuring up childhood memories of Captain Caveman eating anything in sight, the modern day Paleo diet has been proposed to consist of meat from grass-fed animals, fish, fresh fruit & vegetables (tinned produce only became available in early 19th Century), eggs, nuts, seeds and plant based oils whilst all grains, legumes (beans, lentils, peas), processed foods, refined sugars, dairy and salt are off the menu. To sum up, Paleo is low carb with an abundance of protein and healthy fats.
So what’s the history behind the Paleo diet? In 1985 the New England Journal of Medicine published an article by Eaton & Konner who proposed that chronic diseases which plague the modern world, namely obesity, diabetes and heart disease are the result of leaving our hunter-gatherer activity and dietary practices back in the stone age. Whilst I’m not going to argue that modern day unhealthy lifestyles are much to blame, there are a number of flaws to their proposal.
Firstly, we can’t say for certain what Palaeolithic man actually ate as getting evidence from more than 10,000 years ago is understandably not straight forward so what has been proposed as a modern Paleo diet is based on assumption rather than fact. Secondly, advocating we should go back to a hunter-gatherer lifestyle to prevent chronic disease suggests this was a healthier lifestyle whereas in fact skeletons from that time show life expectancy was no more than 35yrs and infant and maternal mortality was high with starvation being a common occurrence.
Finally, the argument that we are genetically predisposed to eat like cavemen and thus not designed to tolerate forbidden Paleo foods such as wheat and dairy is also flawed. The concept that the human body has not kept pace with our rapidly evolving culture, as we’ve moved out of our caves, to be able to adapt and survive is quite simply unscientific. Genetic studies have shown how we have adapted to changes in our diets since agriculture was introduced, for example being able to metabolize lactose in milk and digesting starchy carbohydrates.
Paleo & Health
If we look at the general principles, the Paleo diet does have some positives such as eating more natural and less processed foods, however this approach can also be adopted through a balanced diet without the need to cut out whole food groups that provide a wealth of other essential nutrients. The few studies that have looked at potential health outcomes from going Paleo, have been mainly in those who are overweight or have diabetes and like with many other dietary interventions that cut out the junk and thus calories, if an individual can stick to it they’ll see a positive outcome.
However, herein lies a fundamental shortcoming; compliance. Following a true Paleo diet is not easy, nor does it provide you with all your nutritional needs which in the long term is not healthy and thus has led to the modified Paleo; Paleo + ancient grains or Paleo + dairy. So, essentially Paleo + the foods you don’t want to give up which brings me back to my previous balanced diet advice…….
Paleo & Running
Ultimately, going Paleo means low carb, which for runners trying to go the distance and run the best they can is not conducive. Research has shown those on a low carb diet can exercise at about 50% VO2 max so could finish a marathon but not at a higher intensity when the body’s main fuel is carbs, to get that PB. This has led to the original authors bringing out ‘The Paleo Diet for Athletes’ as even they accept carbs are non-negotiable for endurance athletes and thus ‘allowing’ you to have carbs before, during and after exercise that exceeds an hour. Perhaps, unsurprisingly, that’s why there is no scientific evidence on following a Paleo diet and athletic performance.
So in a Paleo ‘nutshell’, whilst there are some good take home messages from a Paleo approach such as getting back to basics and eating less processed foods, the rationale for eating like our ancestors is questionable and essentially it does not meet all your nutritional needs for health or running performance.