The Paleo diet mimics the presumed dietary patterns of early humans during the Paleolithic era. It focuses on consuming whole, unprocessed foods available to hunter-gatherers thousands of years ago. Many modern dietary staples are excluded due to their relatively recent introduction into the human diet, emerging with agriculture and industrial food processing.
Grains and Legumes
The Paleo diet excludes all grains and legumes. The rationale is that agriculture, which introduced these foods as widespread staples, is a relatively recent development in human history, beginning approximately 10,000 years ago. This timeframe is considered too short for human genetics to have fully adapted to their consumption.
Common grains to avoid include wheat, rice, corn, oats, barley, and rye. Even pseudograins like quinoa and buckwheat are generally excluded. Legumes, such as beans, lentils, peanuts, and soy, are also not part of the Paleo diet.
The primary concern with both grains and legumes stems from antinutrients, specifically lectins and phytates. Lectins are proteins that can interfere with nutrient absorption and cause digestive issues. Phytates can bind to minerals like zinc, calcium, and iron, reducing their absorption in the body.
Dairy Products
Dairy products are largely excluded from the Paleo diet. The widespread consumption of animal milk only became common after the domestication of animals, a practice that emerged well after the Paleolithic era. Therefore, from a strict ancestral perspective, dairy is considered a modern food.
This exclusion applies to most dairy items, including milk, cheese, yogurt, butter, and cream. Reasons for avoiding dairy include concerns about lactose, which many adults globally have difficulty digesting due to a decline in the lactase enzyme after infancy. Certain milk proteins like casein may also contribute to inflammatory responses. While some flexible interpretations of Paleo might permit certain fermented dairy products or ghee, strict adherence typically avoids all dairy.
Processed Foods and Unhealthy Additives
The Paleo diet emphasizes avoiding processed foods and unhealthy additives. Modern industrial food production introduces substances not present in ancestral diets, which are believed to contribute to various health issues. Any food that has undergone significant industrial processing is generally excluded.
This includes all refined sugars (e.g., white sugar, high-fructose corn syrup, agave nectar) and artificial sweeteners. These provide calories without nutrients and can cause rapid blood sugar fluctuations.
Processed vegetable oils like soybean, corn, canola, sunflower, and safflower oils are also avoided due to their high omega-6 fatty acid content and their industrial extraction processes. Artificial ingredients, including colors, flavors, and preservatives, are not permitted as they are synthetic compounds with no historical dietary precedent.
Beyond specific ingredients, a wide range of highly processed foods like fast food, most packaged snacks, breakfast cereals, and deli meats are excluded. Refined table salt, often stripped of natural minerals and containing anti-caking agents, is generally avoided, though unrefined salts may be used sparingly. Most alcoholic beverages are also typically excluded due to their sugar content, grain or fruit bases, and processing, although some interpretations might allow certain less-processed options like wine or specific spirits in moderation.