Paleo diet: the evidence behind eating like our ancestors
Published on ·Updated on ·5 min read
<p>Eat what a hunter-gatherer would eat. That is the simple premise of the paleo diet: meat, fish, vegetables, fruit, nuts and seeds — and nothing that would have required agriculture to produce. No grains. No dairy. No legumes. The idea is compelling: our genes are shaped by hundreds of thousands of years of pre-agricultural eating, and modern food is making us sick. But how well does the evidence support this theory, and what does the diet actually achieve in practice?</p>
<h2>Key takeaways</h2>
<ul>
<li>The paleo diet excludes grains, dairy, legumes and all processed foods, emphasising meat, fish, eggs, vegetables, fruit and nuts.</li>
<li>Short-term evidence is positive: weight loss, improved [blood sugar](/en/blog/normal-blood-sugar) and lower blood pressure compared to control diets.</li>
<li>Long-term evidence is limited; most studies are small and under six months.</li>
<li>The evolutionary rationale is contested — humans adapted to agricultural foods faster than the theory suggests.</li>
<li>Excluding dairy and legumes raises real nutritional concerns, particularly for calcium and fibre.</li>
<li>A flexible paleo-inspired approach delivers the core benefits with fewer restrictions and better long-term sustainability.</li>
</ul>
<h2>What is the paleo diet?</h2>
<p>The term "Paleolithic diet" was popularised by gastroenterologist Walter Voegtlin in the 1970s and later developed by scientist Loren Cordain in his 2002 book <em>The Paleo Diet</em>. The central argument: human genetics are adapted to hundreds of thousands of years of hunter-gatherer eating. The agricultural revolution 10,000 years ago was, in evolutionary terms, extremely recent. Our digestive systems are not optimally adapted to grains, dairy or legumes — and the chronic diseases of modern life are partly the consequence.</p>
<p>The evolutionary argument is intuitive but scientifically more complicated. Evidence shows that humans were consuming starchy tubers and grains much earlier than 10,000 years ago. More importantly, humans show clear signs of recent adaptation to agricultural foods — amylase gene duplications for starch digestion being a well-documented example. The "our genes haven't changed" argument is an oversimplification.</p>
<h2>What do you eat?</h2>
<h3>Permitted foods</h3>
<p>Grass-fed and wild-caught meat, poultry, fish and seafood form the protein foundation. Eggs. Vegetables in large quantities, including starchy varieties like sweet potato and butternut squash. Fruit — in moderation due to fructose content. Nuts and seeds (excluding peanuts, which are legumes). Olive oil, coconut oil and avocado oil as cooking fats.</p>
<h3>Excluded foods</h3>
<p>All grains are off limits: wheat, rye, [oats](/en/blog/oatmeal-for-weight-loss), rice, corn. Dairy in all forms: milk, cheese, yoghurt, butter. Legumes: lentils, chickpeas, kidney beans, soy. Refined sugar and all processed foods. Salt is restricted in strict versions; alcohol is also typically excluded.</p>
<h2>The dairy exclusion debate</h2>
<p>Excluding dairy is one of the most contested aspects of the paleo diet. Dairy is an excellent source of calcium, vitamin D and protein. In populations with thousands of years of dairy consumption, lactase persistence genes are widespread — a textbook example of rapid human adaptation to agricultural foods. The claim that dairy is "non-paleo" and therefore harmful is not supported by the evidence for the majority of adults with dairy tolerance.</p>
<p>That said, people with lactose intolerance or dairy allergies may genuinely benefit from elimination. And for people whose dairy consumption consists largely of highly processed products — flavoured yoghurts, processed cheese — removing them can improve overall diet quality regardless of the paleo rationale.</p>
<h2>What the evidence shows</h2>
<p>A 2019 systematic review published in the <em>American Journal of Clinical Nutrition</em> analysed 11 randomised controlled trials of the paleo diet. Conclusion: short-term paleo diets produced significant improvements in weight, waist circumference, blood pressure and fasting blood sugar compared to control diets. At longer time points — beyond six months — the advantages became less clear, and the evidence was insufficient to support strong recommendations.</p>
<p>An Australian study comparing paleo to national dietary guidelines in people with type 2 diabetes found no significant differences in blood sugar control after two years — though both groups improved. What is difficult to disentangle in paleo research is whether the specific exclusions (grains, dairy, legumes) drive the benefits, or whether eliminating ultra-processed food and sugar — which happens automatically on a paleo diet — is the main driver of improvement.</p>
<h2>Practical benefits</h2>
<p>High protein and fibre intake produces strong satiety. Many people adopting paleo automatically eat fewer calories — not through deliberate restriction but because snacking shifts from processed foods to nuts, fruit and boiled eggs. The emphasis on vegetables and quality protein substantially improves overall diet quality.</p>
<p>People with gluten sensitivity or FODMAP-related gut issues may benefit from eliminating grains and legumes, even if the underlying paleo theory is not the correct explanation. Short-term weight loss is well-documented and driven by both the elimination of calorie-dense processed foods and the high satiety of protein. Our guide on <a href="/en/blog/calorie-deficit-calculator">calculating a calorie deficit</a> can help you understand how to set specific weight loss targets.</p>
<h2>Drawbacks and limitations</h2>
<p>Excluding dairy, legumes and whole grains creates genuine nutritional gaps. Calcium is the most significant: while leafy greens and almonds contain calcium, their bioavailability is lower than dairy. Without deliberate supplementation or careful food selection, calcium deficiency is a real risk on a strict paleo diet over the long term.</p>
<p>Fibre intake also warrants attention. Whole grains and legumes are among the richest fibre sources in typical Western diets. Replacing them requires consistently high vegetable intake to maintain gut health and microbiome diversity.</p>
<p>The financial cost is higher than most diets. Grass-fed beef, wild-caught fish and organic produce carry significant price premiums over staples like bread, pasta and dairy. This limits accessibility for many households. Social sustainability is another challenge — avoiding bread, pasta, cheese and legumes at social events, restaurants and other people's homes requires constant negotiation.</p>
<h2>Paleo vs. Mediterranean vs. low-carb</h2>
<p>How does paleo compare to other popular patterns? The <a href="/en/blog/mediterranean-diet">Mediterranean diet</a> has a far stronger long-term evidence base and is considerably more socially sustainable — it includes legumes, whole grains and dairy in moderate amounts. The <a href="/en/blog/low-carb-diet">low-carb diet</a> shares the emphasis on protein and fat but allows dairy and legumes, making it more nutritionally complete and flexible.</p>
<p>Paleo's strongest contribution is its core principle: eat unprocessed, real food and eliminate refined sugar and industrial products. That principle is well supported by evidence. The specific exclusions — no grain of any kind, no dairy at all — are less scientifically justified and make the diet harder to follow without meaningful additional benefit for most people.</p>
<h2>How to get started</h2>
<p>Consider starting with a less strict interpretation. Eliminate all ultra-processed foods, refined sugar and refined grains first. Add more vegetables and high-quality meat and fish. Decide for yourself whether to exclude legumes and dairy based on your individual response. A hybrid approach — paleo as a framework and inspiration, with some flexibility — is more sustainable for most people and likely equally effective.</p>
<p>Tracking nutritional intake is particularly useful when starting paleo, since the macro composition changes substantially. Moveno lets you photograph meals and see an instant nutritional breakdown — useful for monitoring protein, fat and fibre without manually logging every ingredient. This matters especially when shifting away from familiar reference points like bread and dairy portions.</p>
<h2>Sources</h2>
<ul>
<li>Ghaedi E et al. (2019). Effects of a Paleolithic Diet on Cardiovascular Disease Risk Factors. <em>American Journal of Clinical Nutrition</em>. <a href="https://doi.org/10.1093/ajcn/nqz007">doi.org</a></li>
<li>Masharani U et al. (2020). [Metabolic](/en/blog/boost-metabolism) and physiologic effects from consuming a hunter-gatherer (Paleolithic)-type diet. <em>European Journal of Clinical Nutrition</em>. <a href="https://www.nature.com/articles/ejcn2015193">nature.com</a></li>
<li>Voedingscentrum (2024). Paleo dieet. <a href="https://www.voedingscentrum.nl">voedingscentrum.nl</a></li>
<li>Gezondheidsraad (2022). Richtlijnen goede voeding. <a href="https://www.gezondheidsraad.nl">gezondheidsraad.nl</a></li>
</ul>
