Whole30 Diet: Complete Guide
Last updated: 20 February 2026
The Whole30 diet (also written as Whole 30 diet) is a 30-day elimination eating plan. For 30 days you avoid grains, legumes, dairy, added sugar, alcohol, and certain food additives. You eat meat, fish, eggs, vegetables, fruit, nuts (except peanuts), seeds, and healthy oils. The idea is to “reset” and then reintroduce foods to see how they affect your energy, digestion, and wellbeing. The Whole30 diet is not marketed primarily as a weight-loss diet–it is an elimination and reintroduction protocol. This guide explains what the Whole30 diet is, how it works, what to eat and avoid, benefits and risks, and a sample day. This page is for education only. Talk to your doctor or dietitian before starting any elimination diet.
Disclaimer: The information on this page is for education only and does not replace advice from your doctor or dietitian. Elimination diets are not suitable for everyone. If you have a history of eating disorders, are underweight, or have a medical condition, get professional guidance before starting the Whole30 diet.
Below: what the Whole30 diet and Whole 30 diet are, how the 30-day reset and reintroduction work, what to eat and avoid, benefits and risks, a sample day, and answers to common questions. You can use our calorie calculator and TDEE calculator to tailor your intake if you have a weight or calorie goal.
What is the Whole30 diet?
The Whole30 diet (or Whole 30 diet) was created by Melissa Hartwig Urban. It is a 30-day programme with strict rules: no grains (including wheat, rice, oats, corn), no legumes (beans, lentils, peanuts, soya in most forms), no dairy, no added sugar (including honey, maple syrup, artificial sweeteners), no alcohol, and no certain additives (e.g. carrageenan, MSG, sulphites in specific forms–check the official list). You eat whole foods: meat, poultry, fish, eggs, vegetables, fruit, nuts (except peanuts), seeds, and healthy oils (olive, coconut, avocado). The programme also discourages recreating baked goods or “treats” with approved ingredients (no “Whole30 brownies”). After 30 days you do a structured reintroduction to see which food groups affect you. The Whole30 diet is similar in allowed foods to the paleo diet but is time-limited and has additional rules. See our anti-inflammatory diet for a less restrictive approach that also emphasises whole foods.
Core principles
- 30 days of strict elimination–no grains, legumes, dairy, added sugar, alcohol, or listed additives.
- Eat whole foods: protein, vegetables, fruit, nuts, seeds, healthy oils.
- No stepping on the scale (official rule)–focus is on how you feel, not weight. After 30 days, reintroduce food groups one at a time to identify triggers.
How the Whole30 diet works
The Whole30 diet works as an elimination diet: by removing common trigger foods for 30 days, you may notice changes in energy, digestion, skin, or other symptoms. Reintroduction then helps you see which foods (if any) cause problems when you add them back. The programme does not require calorie counting–you eat until satisfied from allowed foods. Some people lose weight because they cut out many calorie-dense processed foods and sugar; others do not. The official stance is that Whole30 is not a weight-loss diet. If you want to manage weight, you can use our calorie calculator and TDEE calculator with your doctor’s or dietitian’s guidance. There is only one “phase”–30 days of elimination, then reintroduction. If you break a rule, the programme says to start over from day 1; some people and health professionals find this all-or-nothing approach too strict. Discuss with your dietitian whether a modified approach is better for you.
What to eat and what to avoid
The table below is a general guide for the Whole30 diet and Whole 30 diet. Always check the official Whole30 rules and ingredient lists (e.g. for additives) if you follow the programme strictly.
| Eat (Whole30 diet) | Avoid |
|---|---|
| Meat, poultry, fish, seafood, eggs | All grains (wheat, rice, oats, corn, etc.) |
| Vegetables (all, including potato) | All legumes (beans, lentils, chickpeas, peanuts, soya in most forms) |
| Fruit | Dairy (milk, cheese, yogurt, butter from milk–ghee is allowed) |
| Nuts and seeds (except peanuts) | Added sugar (table sugar, honey, maple syrup, artificial sweeteners) |
| Healthy oils (olive, coconut, avocado); ghee | Alcohol; certain additives (check official list) |
No “junk” recreated with approved ingredients (e.g. pancakes, biscuits) in the official programme. For a less strict whole-foods approach, see our paleo diet and weight loss diet guides.
Potential benefits (with caveats)
Benefits are described in general terms–individual results vary. This is not medical advice.
- Identifying triggers: The Whole30 diet and structured reintroduction can help some people notice which foods affect their energy, digestion, or other symptoms. That can inform a personal long-term way of eating.
- Whole foods: Eating mostly unprocessed foods for 30 days may improve diet quality and reduce added sugar and processed ingredients.
- Habit reset: Some people find the 30-day structure useful to break habits around sugar or alcohol. Others find the rules stressful–it depends on the person.
Evidence: elimination diets are used in clinical practice for certain conditions (e.g. food intolerance); the Whole30 programme itself is not a medical protocol. Diet does not replace medical care. Weight loss is not guaranteed and is not the stated goal of Whole30.
Risks and who should be cautious
The Whole30 diet is restrictive and is not for everyone.
- Eating disorders: The strict rules and “start over” mentality can be harmful for people with a history of restrictive eating or eating disorders. If this applies to you, speak to a healthcare professional before starting the Whole 30 diet.
- Underweight or nutrient needs: Eliminating grains and legumes can make it harder to get enough calories or fibre. If you are underweight or have high energy needs, the Whole30 diet may not be appropriate without dietitian support.
- Medical conditions: If you rely on legumes, dairy, or grains for health reasons (e.g. some gut conditions, allergies), do not start an elimination diet without your doctor’s or dietitian’s approval.
- Pregnancy and breastfeeding: Get advice before starting the Whole30 diet–adequate calories and variety matter.
Before starting the Whole30 diet, talk to your doctor or dietitian.
Sample Whole30 diet day
This is one example of a day that fits the Whole30 diet and Whole 30 diet rules. No grains, legumes, dairy, added sugar, or alcohol.
- Breakfast: Scrambled eggs with spinach and mushrooms, avocado, and a piece of fruit. Or a frittata with vegetables and compliant sausage (check ingredients).
- Lunch: Large salad with grilled chicken or tinned tuna (no added sugar), olive oil and lemon, nuts, and vegetables. Fruit if desired.
- Dinner: Grilled salmon or chicken with roasted vegetables (e.g. sweet potato, broccoli, peppers) and a side salad. Use olive oil or ghee. No grains or legumes.
- Snacks: Fruit, vegetable sticks, a handful of nuts, or a hard-boiled egg. No dairy, no cereal bars, no added sugar.
Use our calorie calculator if you want to check intake; the programme does not require it. See our paleo diet and anti-inflammatory diet for related whole-foods approaches.
Frequently asked questions
The Whole30 diet (or Whole 30 diet) is a 30-day elimination eating plan. You avoid grains, legumes, dairy, added sugar, alcohol, and certain additives. You eat meat, fish, eggs, vegetables, fruits, nuts, seeds, and healthy oils. It is designed as a ‘reset’ to see how foods affect you; after 30 days you reintroduce foods. It is not primarily a weight-loss diet.
On the Whole30 diet you can eat: meat, poultry, fish, eggs; vegetables; fruit; nuts and seeds (except peanuts); healthy oils (olive, coconut, avocado). You cannot eat: grains, legumes (including peanuts and soya in most forms), dairy, added sugar (including honey, maple syrup), alcohol, or certain additives. See the article table for the full list.
The Whole30 diet is 30 days of strict elimination. If you break a rule, the official programme says to start over from day 1. After 30 days you do a structured reintroduction to see which food groups affect your energy, digestion, or other symptoms. Many people then adopt a less strict long-term way of eating based on what they learned.
Similar but not the same. Whole30 is stricter for 30 days: no added sugar, no alcohol, no baked goods or treats even with ‘approved’ ingredients (no recreating junk food). Paleo allows some flexibility (e.g. paleo treats, natural sweeteners). Whole30 is a short-term reset; paleo is often a long-term diet. The allowed food list is similar (no grains, no legumes, no dairy).
Yes. The Whole30 programme does not require calorie counting, but if you want to lose or maintain weight you can use our calorie calculator and TDEE calculator as a guide. Whole30 can reduce calories by cutting out many processed foods and sugar–but focus on eating enough vegetables, protein, and healthy fats so you are not under-eating.
People with a history of eating disorders, restrictive dieting, or who are underweight should be cautious–the strict rules can be triggering. Those with certain medical conditions (e.g. needing legumes or grains for health) or who are pregnant or breastfeeding should get advice first. The all-or-nothing ‘start over’ rule may not be healthy for everyone.
Summary
The Whole30 diet (or Whole 30 diet) is a 30-day elimination plan: no grains, legumes, dairy, added sugar, alcohol, or listed additives. You eat meat, fish, eggs, vegetables, fruit, nuts, seeds, and healthy oils. After 30 days you reintroduce foods to see what affects you. It is not primarily a weight-loss diet. This page is for education only–talk to your doctor or dietitian before starting, especially if you have a history of eating disorders or a medical condition. See our paleo diet, anti-inflammatory diet, and weight loss diet guides for related approaches. Use our calorie calculator and TDEE calculator with your healthcare team’s guidance if you are managing weight.
Use our calculators with this diet
Set your calorie target and plan meals with our free tools.
You might also like
Other diet guides that may fit your goals.
Paleo diet
Whole foods, no grains or legumes. Focus on meat, fish, vegetables.
Low-carb diet
Fewer carbs, more protein and fat. Used for weight loss and blood sugar.
Anti-inflammatory diet
Foods that may help reduce inflammation. Often overlaps with Mediterranean.
Weight loss diet
Balanced eating with a calorie deficit for sustainable weight loss.
Sources and further reading
This article is based on current guidance. For more detail, see:
- Official Whole30 resources for rules, food lists, and reintroduction
- Guidance from dietetic associations on elimination diets and food intolerances
- Information on when elimination diets are appropriate (e.g. with dietitian support)
Last updated: 20 February 2026. Content is for educational purposes only and does not replace medical or dietetic advice.