What To Eat On An Animal-Based Diet

How to Construct an Animal-Based Diet

How you construct an animal-based diet depends on your goals and lifestyle and can vary quite widely. For those who have an autoimmune illness, for example, a complete elimination of plant foods or selectively avoiding specific food groups may be most beneficial. For most people who are approaching this way of eating for the first time, a less restrictive diet is preferable and may produce better health outcomes. This post will focus on the least restrictive animal-based diet.

Before I break down what to eat, it’s important to consider when to eat. As an animal-based diet is so satiating, many people prefer to eat only one or two meals per day. This usually works well for those practicing time-restrictive eating and intermittent fasting, which I have covered here, but is often not sustainable or practical for others. For this reason this meal plan will include 3 meals.

An animal-based diet prioritises nutrient-dense animal foods, which include meat, fish, eggs and dairy (for those who can tolerate it) over plant-based foods. These foods represent the most nutrient-rich sources of bioavailable vitamins and minerals and should make up at least 75% of your diet. The addition of plant foods for flavour, texture and variety should be considered on a spectrum of toxicity and make up a smaller amount of your total diet.

Nutrient Superiority of Animal-Based Foods

While some plant foods contain beneficial vitamins, minerals and antioxidants, they also contain plant defence compounds such as oxalates, phytates and lectins (see Plant Paradox: Anti-Nutrients and Natural Pesticides) that are known to irritate the gut and immune system. These compounds can also have a negative effect on our health, particularly in those who are sensitive to them.

The primary food group to avoid is seeds, including grains, nuts and beans. Nightshades (tomatoes, eggplants, potatoes, goji berries, peppers, paprika, chilli peppers) and leafy vegetables (e.g. spinach, kale, broccoli, cabbage, beetroot) may also be problematic for some people and therefore are best avoided. On the opposite end of the toxicity spectrum are the least toxic plant foods, which are recommended for most people. Generally sweet fruits (flesh only) and non-sweet varieties such as cucumbers, olives, squash and avocados are well tolerated.

Tea and coffee are best avoided as they contain tannins, which impair nutrient absorption and irritate the gut (1) as well as pesticides, mould toxins and acrylamide formed in the roasting process. Herbal teas are a healthier alternative, but are not devoid of toxic compounds. Whether or not to remove them from your diet is often a personal decision, one in which the risk and benefits are weighed up.

What a Typical Day of Eating Looks Like on an Animal-Based Diet


  • 100g grass fed steak
  • 50g of liver
  • 5 egg yolks in 2 tablespoon of butter
  • 2 slices of bacon
  • ½ avocado


  • Tin of sardines
  • 50g of halloumi
  • ½ avocado
  • Cucumber slices
  • Olives
  • 2 tablespoon of extra virgin olive oil


  • 200g slow cooked beef brisket
  • 100g of roasted butternut squash in 2 tablespoon of tallow
  • A pear


  • 8 cups of mineralised water

Macronutrient Ratios on an Animal-Based Diet

When making the switch to an animal-based diet, the body will naturally start to utilise fat as the main form of energy. Depending on your current reliance on carbohydrates, you may experience symptoms of low energy, fatigue and irritability; this is completely normal. Commonly referred to as ‘keto flu’, this phenomenon can last up to a week.

There does seem to be some genetic variability in an individual’s response to ratios of animal fat but in general humans are well suited to oxidising fats for fuel. The amount of fat to eat depends on your body weight goal and your composition. For most adults who want to slim down and maintain lean muscle, aiming for 1-1.5g of fat per gram of protein is ideal. However, I would recommend consuming as much as 1.2-2g of protein per kg of body weight per day. As an 80kg adult male I consume 160g of protein and 180-270g of fat per day.

Depending on whether you prefer to remain in ketosis or increase your athletic performance, adding in some of the least problematic carbohydrates such as honey, white rice and sweet potatoes is up to you. For a visual representation, I have included the macronutrient ratios of the example meal plan below.

Optimising an Animal-Based Diet

No animal-based diet is complete without considering organ meats such as liver, kidney and heart. Each provides a unique variety of vitamins and minerals, with liver being the most nutrient dense. Please refer to the nutrient comparison chart on my Animal-based foods for optimal health blog post for a full appreciation for its nutrient superiority over other foods. It’s important to point out that restricting your diet to mainly muscle meat may make it harder to obtain enough vitamin C, B2, B9, K2, potassium, magnesium and copper, which is why I recommend eating 50g of organ meat every other day. The chart below highlights the nutrient composition of the example meal plan.

A Word on Dairy

Sensitivities to dairy are not uncommon and generally there are two types. Those who are lactose intolerant and will likely experience immediate digestive discomfort and those who are intolerant to the casein protein found in the milk and may experience a delayed immune response. There are two different types of casein. A1 casein is found only in cow’s milk and A2 casein is found in sheep, goat and some cow’s milk such as Guernsey. Although some people can be sensitive to both types of casein, generally it is the A1 type that is most problematic. The A1 variant of casein becomes beta-casomoprhin 7, a molecule that activates the immune system, triggers inflammation and is linked to autoimmune disease (2)(3).

The selective exclusion of A1 milk may help some people but I would recommend avoiding dairy altogether for 60 days when starting an animal-based diet. However, considering that dairy is a good source of calcium, which is generally hard to obtain on an animal-based diet, if you can tolerate dairy then including it in your diet is a good idea. Selecting unpasteurised dairy products will help ensure you receive the unadulterated beneficial microbes, as well as fatty acids, which are critical for supporting the health of your gut.

Hopefully, this has provided you with a good overview of what to eat on an animal-based diet. It’s important to remember this is only a template and will vary depending upon your goals, current state of health and preferences.

  1. Griffiths DW. The inhibition of digestive enzymes by polyphenolic compounds. Adv Exp Med Biol. 1986;199:509–16.
  2. Elliott RB, Harris DP, Hill JP, Bibby NJ, Wasmuth HE. Type I (insulin-dependent) diabetes mellitus and cow milk: Casein variant consumption. Diabetologia. 1999;42(3):292–6.
  3. Pal S, Woodford K, Kukuljan S, Ho S. Milk intolerance, beta-casein and lactose. Vol. 7, Nutrients. MDPI AG; 2015. p. 7285–97.

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