The low-down on Paleo – Welcome to our three part series on the Palaeolithic diet.
The Paleo Diet is one of the hottest diet trends around, mostly due to celebrity followers and gym goers. There are even Paleo cafes – not that they existed in Paleo times, nor did the coffee they serve!
There is debate whether the Paleo Diet is truly healthy or not. Higher-protein diets have been examined in research and a local version has been promoted by the Commonwealth Scientific and Industrial Research Organisation (CSIRO), called the Total Wellbeing Diet[i]. However, compared to the Paleo Diet, the CSIRO Total Wellbeing Diet has been extensively studied in a variety of groups. Palaeolithic diets were first suggested by Eaton and Konner in 1985[ii] on the basis that current day chronic metabolic disorders have resulted from a gene-culture mismatch and the human body’s inability to adapt from Palaeolithic times[iii]. Yet there are multiple examples suggesting that this is simply not true.
The Paleo Diet – What is it?
The Palaeolithic period is a period of human history extending from approximately 2.5 million to approximately 10,000 years ago. Early in this period, people ate primarily vegetables, fruit, nuts, insects, roots, and meat, which varied depending on season and availability. Scavenging and gathering food eventually lead to hunting larger animals. Depending on where Palaeolithic man was located, a great deal of meat may have been consumed by cooking over an open fire (approximately 400,000 years ago). However, the simple grinding and pounding of food ingredients was far more likely as a method of cookery prior to this. The diet tended to be higher in protein, lower in fat but with more essential fatty acids, and was lower in sodium and higher in fibre. However, it is incorrect to suggest that the carbohydrate content was low. Instead, carbohydrate came from other food sources and there was a wide range in the level of consumption which was based on location and season.
FACT: There was not one Paleo Diet
Based on research examining the types and quantities of food our hunter-gatherer ancestors ate, the meat portion was lean and included ostrich, bison (including the organ meats) and seafood. It also included fresh fruit, insects, and non-starchy vegetables. Yet, modern lifestyles mean that we spend most of our day-light hours at work, rather than hunting and gathering. Most of our food is hunted down between the aisles and gathered in a large shopping trolley! It is simply not possible to find the appropriate foods (the variety or the type of food) in the modern era to match the Paleo Diet of the past. Furthermore, when the affordability of this type of diet was assessed, based on a US diet model, the results suggested a 9.3% increase in income is needed to achieve nutrient targets (except calcium)[iv]. The same study also comments on adherence; the published research about Paleo Diets to date all had small numbers of participants (n<30)and large drop-out rates as consumers typically had trouble making the large dietary changes necessary to follow the Paleo Diet.
FACT: The Paleo Diet is expensive and hard to sustain
Agriculture came only approximately 12,000 years ago, so individuals and whole communities in Palaeolithic times worked together to hunt, gather and then cultivate crops. This new period is termed the Neolithic era and although the change in diet was not sudden, there is proof from this period that humans continued to evolve and at a more accelerated rate than during the Palaeolithic period. Gene studies of this period indicate starch consumption (from genes that code for amylase production) and milk consumption (from genes that code for lactase which is persistent after weaning and into adult years) which could have only occurred after humans had developed dairy practices.
FACT: People kept changing and adapting after the Paleo period. We ate starchy foods and drank milk!
Although the food types and quantities suggested in the Australian Dietary Guidelines (ADGs) differ from Palaeolithic dietary patterns, many of the same fresh choices are emphasised. Unfortunately, we know many Australians do not eat the recommended two serves of fruit or five serves of vegetables each day. So many people are eating less than our ‘cavemen’ ancestors consumed, and a much narrower selection of the food types than was consumed during these periods. The most recent dietary survey suggests that only 5.5% of Australian adults have adequate daily intake of fruit and vegetables while more than 40% of energy is derived from ‘extra’ or ‘discretionary’ foods and drinks that provide very little nutritional value[v].
FACT: Most Australians need to eat more fruit and vegetables and less ‘extra’ foods – but this need not be Paleo!
In summary, the precise diet consumed by Palaeolithic man would be difficult to replicate today. Any modern reconstruction of the diet is more likely to be based on ‘fashion’ than science. While the ADGs are based on strong evidence from more than 55,000 studies, a Palaeolithic diet has been studied in very few people and not over the long term.
[i] Belinda Wyld, Adam Harrison and Manny Noakes (2010). The CSIRO Total Wellbeing Diet Book 1: sociodemographic differences and impact on weight loss and well-being in Australia. Public Health Nutrition, 13, pp 2105-2110. doi:10.1017/S136898001000073X.
[ii] Eaton SB, Konner M. Paleolithic nutrition: a consideration of its nature and current implications. N Engl J Med. 1985;312:283–289.
[iii] Turner, B. L. and Thompson, A. L. (2013), Beyond the Paleolithic prescription: incorporating diversity and flexibility in the study of human diet evolution. Nutrition Reviews, 71: 501–510. doi: 10.1111/nure.12039
[iv] Matthew Metzgar, Todd C. Rideout, Maelan Fontes-Villalba and Remko S. Kuipers (2011) The feasibility of a Paleolithic diet for low-income consumers. Nutrition Research Volume 31, Issue 6, pp 444-451 doi:10.1016/j.nutres.2011.05.008
[v] Australian Bureau of Statistics (2014) Australian Health Survey: Updated Results, 2011-2012 http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/4364.0.55.003main+features12011-2012 Accessed July 2014.
The Palaeolithic diet has been suggested as a solution to modern day diet-related diseases. However, a high protein, high fat, low carbohydrate diet with no dairy products or grains is not supported by the extensive body of research that is currently available.
Although replacing processed ‘extra’ or ‘discretionary’ foods with whole foods is sensible and emphasised in the Australian Dietary Guidelines (ADGs), there has been criticism directed at the Paleo diet. Excluding whole food groups is not wise, and strict followers may risk falling short on key nutrients. The Paleo diet encourages foods high in protein to substitute for many carbohydrate food choices and this is not only controversial, but incorrectly glorified as being advantageous for health. Dairy foods, grains, legumes and some processed oils recommended in the ADGs are excluded from the Paleo diet. These foods contain beneficial nutrients, and are high satiety food choices.
It is also important to emphasise that there was not one Paleolithic diet, and consequently there is evidence that during that time frame, from about 30,000 years ago, people ate both grains and legumes.
The Pros and Cons of Going Paleo
|Fruit and Vegetables|
|Grains and Grains-Based Foods|
What does the research say?
Seven studies from 2006-2013 examine the effects of a Palaeolithic type diet [i,ii,iii,iv,v,vi,vii]. These are all small, short-term studies, some of which even lack a control group! The most recently published study reviewed the satiety effects of the Paleo diet compared to the normal diabetic diet with 13 patients who served as both the treatment and as the control group over two consecutive three-month periods. The authors concluded that the Paleo diet was found to be more difficult to adhere to and each diet was found to be equally satiating, although there were per calorie differences. Weight loss was not recorded in this study.
Overall, when these studies have reported beneficial effects in blood pressure levels, blood cholesterol and triglycerides, it must be recognised that these positive changes were not independent of weight loss. Therefore, we cannot say that improvements to blood pressure, cholesterol and triglycerides are a result of the diet since this is exactly what should happen when you lose excess body weight! There are problems with the dietary methodology in these studies (i.e. no nuts included in the control Mediterranean diet), no long-term follow-up to assess compliance, or acceptability of the diet or weight maintenance effects. There are simply not enough good quality studies to suggest a Paleo diet would be advantageous. Furthermore, a feasibility study in the US suggested a 9.3% increase in income would be required to meet nutrient targets!
There are simply not enough good quality studies to suggest a Paleo diet would be advantageous.
The modern Paleo diet has been tested in very few people and only over the short term. Participants often drop out of the studies because the diet is difficult to adapt to and it is reportedly more expensive. While the emphasis on fruit and vegetables, and high- quality food choices rather than processed options is a positive feature, the diet fails to provide all nutrients as per current recommendations and excludes foods and whole food groups.
[i]Jonsson T, Ahren B, Pacini G, Sundler F, Wierup N, Steen S, Sjoberg T, Ugander M, Frostegard J, Goransson Lindeberg S (2006). A Paleolithic diet confers higher insulin sensitivity, lower C-reactive protein and lower blood pressure than a cereal-based diet in domestic pigs. Nutr Metab (Lond), 3:39.
[ii]Lindeberg S, Jonsson T, Granfeldt Y, Borgstrand E, Soffman J, Sjostrom K, Ahren B (2007) A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease. Diabetologia, 50(9):1795-1807.
[iii]Osterdahl M, Kocturk T, Koochek A, Wandell PE (2008) Effects of a short-term intervention with a paleolithic diet in healthy volunteers. Eur J Clin Nutr, 62(5):682-685.
[iv]Jönsson T, Granfeldt Y, Ahrén B, Branell UC, Pålsson G, Hansson A, Söderström M, Lindeberg S. (2009). Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study. Cardiovasc Diabetol.;8:35
[v]Frassetto LA, Schloetter M, Mietus-Synder M, Morris RC, Jr., Sebastian A (2009) Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet. Eur J Clin Nutr; 63, 947-955.
[vi]Jonsson T, Granfeldt Y, Erlanson-Albertsson C, Ahren B, Lindeberg S. (2010) A Paleolithic diet is more satiating per calorie than a Mediterranean-like diet in individuals with ischemic heart disease. Nutr Metab (Lond). Nov 30;7(1):85
[vii]Jönsson T, Granfeldt Y, Lindeberg S, Hallberg, A (2013) Subjective satiety and other experiences of a Paleolithic diet compared to a diabetes diet in patients with type 2 diabetes Nutrition Journal, 12:105 http://www.nutritionj.com/content/12/1/105
When giving dietary advice, considering the health of the population is of critical importance. Many Australians are overweight, and are seeking options for weight loss. Accredited Practising Dietitians (APDs) adapt the current Australian Dietary Guidelines (ADGs) to assist individuals with weight loss, considering their lifestyle, food preferences, food availability, economic factors and their current health status. A diet written in a magazine or a book, cannot provide this level of expert, tailored advice.
The Palaeolithic diet is being promoted by celebrities who have no responsibility in terms of providing individual diet or health advice.
The Palaeolithic diet is being promoted by celebrities who have no responsibility in terms of providing individual diet or health advice. In fact, if your health deteriorates from following their diet, they cannot be held responsible. A health professional, such as an APD, takes responsibility for your health when they provide advice, supporting you until you reach your long-term health goals rather than giving you information and then leaving you to try and adapt your life to the new principles.
A health professional, such as an APD, takes responsibility for your health when they provide advice.
While the Paleo diet focuses on fresh foods, as do the ADGs, there is too much emphasis on protein foods for most people. It is rare that individuals need more than 1g of protein per kilogram of lean body mass and currently most Aussies eat double this recommendation! The focus in Australia should be on getting enough high iron food choices in our diets, because while we all seem to get enough protein, there are some key population groups (mostly girls and young women) who do not get enough iron.
Carbohydrate foods provide essential nutrients, fibre and are an important fuel for the helpful bacteria that live in our gut.
The Paleo diet may be too low in carbohydrate for some people, for example those who regularly participate in exercise and sport. For people with pre-existing conditions like diabetes mellitus, following this sort of plan can be particularly problematic as the risks to kidney health from consuming more protein is uncertain, especially over the longer term. Carbohydrate foods are used in therapeutic diets for diabetes to help maintain blood sugar levels within a tight range. Demonising carbohydrate foods can therefore be misleading, because although foods are often grouped together as carbohydrates, there is a great deal of variety between the food types. Carbohydrate foods provide essential nutrients, fibre and are an important fuel for the helpful bacteria that live in our gut. The bacteria, or probiotics, are now known to help with prevention of bowel disease.
It is important to remember though that no one who lived in the Palaeolithic era actually consumed coconut oil as they had no means of extracting and refining it!
Foods high in