Understanding Popular Diets: Paleo, Keto, AIP, GAPs and More

Many students who come through the virtual doors of the Culinary Nutrition Expert Program are confused about what to eat. There are a wide range of popular diets that have emerged in recent years, each with its own set of rules and reasons why it’s the ‘best’ diet to follow. With all of the options out there, how do we know what to eat and how to design an ideal diet that works for our optimal health?

Let’s talk about some of the most popular diets, what they have to offer and how you can begin to choose between them.

Understanding Popular Diets

Note: Before undertaking a specific diet, consult with a health practitioner who can understand your health history and work with you to create a customized protocol.

Comprehensive Elimination Diet

This protocol removes the most common allergens to reduce the potential for a reaction. Often the elimination diet is combined with a rotation diet as a means to identify the foods that are causing a reaction or symptom.

Foods Allowed: Fruits, vegetables, fish, poultry, nuts, seeds, beans, legumes

Foods Restricted: Gluten sources, dairy products, corn, pork, beef, egg, peanuts, soy, shellfish and all processed foods

Acute Healing Diet

The acute healing diet is the holistic version of what conventional nutrition often refers to as ‘low residue diet’. It removes any foods that are difficult to digest or cause too much bulk in the digestive tract. The diet focuses on highly digestible and absorbable sources of calories and nutrients, including broths, fresh juices, fats, and mucilaginous foods.

Foods Allowed: Broths (bone and veggie), cold-pressed juices, healthy fats, nut/seed milks, mucilaginous foods (chia, aloe, etc.)

Foods Restricted: Starchy carbohydrates, beans and legumes, dense animal proteins, whole nuts/seeds, raw vegetables and most solid foods

Anti-Inflammatory Diet

This is a common healing diet that often becomes everyday eating for many people who plan to maintain a low inflammatory response in the body. This diet helps to decrease inflammation by focusing on a high intake of nutrient-rich anti-inflammatory foods. You can get the full scoop from our free Anti-Inflammatory Diet + Lifestyle Guide.

Foods Allowed: Fruits and vegetables, organic/pastured animal products, ghee, nuts/seeds, beans and legumes (except for peanuts), gluten-free whole grains and flours, natural sweeteners

Foods Restricted: Processed foods, cooked rancid oils, gluten sources, dairy products, nightshades, corn, soy, citrus, conventional meats and processed sugar

Paleolithic Diet (Paleo)

The Paleo Diet focuses on foods that our ancestors likely ate. Paleo eating offers an array of health benefits and is often used to address a wide range of autoimmune conditions, blood sugar imbalances, obesity and more.

Foods Allowed: Healthy fats, animal proteins, fruits, vegetables, nuts, seeds, some natural sweeteners

Foods Restricted: Grains, dairy products, processed foods, refined sugars, beans and legumes

Vegan Diet

This plant-based diet excludes all animal products. People follow a vegan diet for health reasons, ethical reasons and environmental reasons. Vegan diets have been used for weight loss, diabetes, cardiovascular disease and more.

Foods Allowed: Fruits, vegetables, nuts, seeds, beans, legumes, grains, plant-based fats and oils

Foods Restricted: Any animal products


This diet requires strict adherence to a diet comprised of foods that don’t have an immediately obvious connection to each other. It omits foods containing Fermentable-Oligo-Di-Monosaccharides-And-Polyols (FODMAPs), which are a family of carbohydrates that can upset the microbiome in certain people. Foods that are removed include a wide range of fruits, vegetables, dairy and meat. This diet is commonly used to address digestive problems such as irritable bowel syndrome (IBS) and small intestinal bacterial overgrowth (SIBO).

Foods Allowed/Restricted: Check out this list for guidelines

Gut and Psychology Syndrome Diet (GAPs)

This diet is commonly used for inflammatory digestive and neurological conditions. It focuses on healing the gut, rebalancing the good bacteria in the gut and enhancing the immune system. There are different phases to the diet and you can add more foods in as you heal.

Foods Allowed: Introductory stages include broths, fermented foods, healthy fats and well-cooked meat and vegetables, while later stages involve adding in different cooking techniques, fermented dairy products, egg yolks, nuts and seeds, raw fruit and raw honey.

Foods Restricted: Depends on the stage of the diet you follow, but generally processed foods, conventional dairy products, raw foods, grains, some vegetables and beans/legumes

Ketogenic Diet (Keto)

The keto diet is a low carbohydrate, high-fat diet. It’s similar to other low-carb diets like Atkins, but instead of replacing carbs with protein, you add in a fat. This sends the body into ketosis, where we start burning fat as our primary source off energy. The ketogenic diet was developed in the 1920s to treat epilepsy and has since been used to help with weight loss, cardiovascular health, diabetes, brain disorders and certain types of cancer.

Foods Allowed: Non-starchy, low carbohydrate vegetables, animal proteins, nuts, seeds, avocado, coconut – you can check out our favourite keto ingredients here

Foods Restricted: All grains, alcohol, sugars, beans and legumes, starchy vegetables (sweet potatoes, winter squash, beets, parsnips, carrots, etc.)

Intermittent Fasting Diet (IF)

Intermittent fasting is going without food for a certain period of time. Fasting cycles vary – anywhere from 16-24 hours, and eating is restricted to a certain window of time. IF is often called an ‘eating pattern’ because it is more about timing and when you eat. Fasting has been shown to improve biomarkers of disease, reduce oxidative stress, and preserve learning and memory function, as has been used as a strategy for weight loss, cardiovascular health, digestion, brain health, athletic performance, and cancer.

Foods Allowed/Restricted: There are no rules about specific foods or food quality – it’s about when you eat, not what you eat

Autoimmune Protocol Diet (AIP)

AIP eliminates certain food chemicals that are believed to contribute to gut dysbiosis and low grade inflammation, as well as autoimmune diseases. By forgoing these foods, the body has the chance to recover. It’s similar to the Paleo diet, but has further restrictions. Once people have completed the restricted elimination phase, there are specific reintroduction phases to add most foods back in. However, many people who follow this diet choose to stick to a Paleo-style diet after the elimination phase.

Foods Allowed: Vegetables, fruits, animal proteins, healthy fats – check out this resource for a full list

Foods Restricted: During the initial stages includes grains, beans, legumes, dairy, sugar, nuts, seeds, chocolate, coffee, eggs, nightshades and certain seed-based spices

How to Choose Between Popular Diets?

It can be difficult to decide which diet to follow. We recommend working with a health practitioner or culinary nutrition expert to determine what is right for you based on your unique health situation. However, there are a few things to think about when deciding what to eat:

  • Severity of symptoms and your current health status
  • Scientific evidence about the effectiveness of a particular diet
  • Willingness to commit to a healing diet for a specific period of time to see if it works for you
  • Time involved in cooking foods from scratch (though meal prepping and batch cooking greatly helps with this!)
  • Cost of food and ingredients
  • Work, lifestyle and family considerations (will you need to make separate meals for the household, bring lunch to work, etc.)
  • Personal and cultural values

Ultimately, there is no one dietary blueprint that works for everyone. We encourage our readers and students to keep an open mind about the wide range of diets that can potentially optimize health, and remember that our diets will evolve over time as our health needs change. Experiment with different diets under the guidance of a health practitioner to figure out what works best for you!

popular diets

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