Evidence-backed eating patterns
Vegan diet
Excludes all animal-derived foods: meat, fish, dairy, eggs, honey and products containing animal ingredients.
What people typically eat
Vegetables, fruit, wholegrains, beans, lentils, soya products, nuts, seeds and fortified plant milks and cereals.
What is restricted
All animal products, including hidden ingredients such as whey, casein, gelatine and some food colourings.
Why people try it
Animal welfare, environment and health are the main drivers.
Realistic advantages
- Typically high in fibre, fruit, vegetables and unsaturated fats
- Associated with favourable weight and cholesterol profiles
- The British Dietetic Association considers well-planned vegan diets suitable for most life stages
Realistic disadvantages
- B12 supplementation is essential, not optional
- Iodine, calcium, iron, zinc, selenium, omega-3 and protein all need planning
- Eating out, travelling and social eating take more effort
Strength of evidence
Moderate evidence
Good evidence that well-planned vegan diets are healthy; less long-term outcome data than for Mediterranean-style patterns.
Likely cost and difficulty
Low ingredient cost; moderate difficulty due to planning and label-reading.
Nutritional risks
B12 deficiency is the headline risk; also iodine, calcium and omega-3. Poorly planned vegan diets can be nutritionally poor.
Who should avoid it
Needs particular care in pregnancy, infancy, childhood and frailty, professional input is recommended at these stages.
Is professional supervision advisable?
Advisable for children, pregnancy, breastfeeding and anyone with medical conditions.
References
Written by the Slimr editorial team. How we review diets.
