Nutricion Vegetariana

Blackwell Science, LtdOxford, UKNBUNutrition Bulletin1471-98272004 British Nutrition Foundation? 2004302132167MiscellaneousVegetarian nutritionF. Phillips

BR IE F IN G PA P ER

Vegetarian nutrition
F. Phillips
British Nutrition Foundation, London, UK

1 2 2.1 2.1.1 3 3.1 3.2 3.3 3.3.1 3.3.2 3.4 3.5 3.6 3.6.1 3.6.2 3.6.3 3.7 4 4.1 4.1.1 4.1.2 4.1.3 4.1.4 4.2 4.3 4.3.1 4.3.2 4.4 4.5 4.6 55.1 5.2 5.3 5.4 5.5 5.6

SUMMARY INTRODUCTION VEGETARIANISM: TRENDS AND TYPES Contemporary vegetarianism in the UK Defining vegetarianism – a range of diets VEGETARIAN NUTRITION Energy Protein Fat Total fat Fatty acids Carbohydrates Alcohol Micronutrients: intakes and status Fat-soluble vitamins Water-soluble vitamins Minerals Key points VEGETARIAN DIETS THROUGH LIFE Infancy and childhoodLacto-vegetarian and lacto-ovo-vegetarian diets Restrictive dietary patters Iron deficiency Growth and development Adolescents Pregnancy and lactation Pregnancy outcome Lactation Athletes Elderly people Key points HEALTH IMPLICATIONS OF VEGETARIAN DIETS Mortality in vegetarians Cardiovascular disease and vegetarian diets Cancer and vegetarian diets Osteoporosis and bone health in vegetarians Otherdiseases Key points

Correspondence: Frankie Phillips, British Nutrition Foundation, 52–54 High Holborn, London WC1V 6RQ, UK. E-mail: frankie@phillips-online.org

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© 2005 British Nutrition Foundation Nutrition Bulletin, 30, 132–167

Vegetarian nutrition

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CONCLUSIONS REFERENCES APPENDICES APPENDIX A: DIETARY RESTRICTIONS OF SELECTED RELIGIOUS GROUPS WHICH RELATE TO MEAT AND FISHCONSUMPTION APPENDIX B: FOODS OF ANIMAL ORIGIN AVOIDED BY VEGETARIANS AND VEGANS APPENDIX C: CHOOSING A BALANCED VEGETARIAN OR VEGAN DIET AND SOURCES OF MICRONUTRIENTS

Summary

The number of people in the UK who claim to be vegetarian has increased dramatically during the last half century; statistics from the Second World War suggest that 0.2% of the population were vegetarian in the 1940sand it is estimated that, in 2000, between 3 and 7% of the population were vegetarian. There is much interest in the potential effects of plant-based diets on a range of health outcomes and nutrition. A range of dietary practices followed by vegetarians has been identified, from the strict guidelines of the most restrictive macrobiotic diets, through vegan and lacto-ovo-vegetarian diets, to thosethat occasionally include fish or even chicken. The type of vegetarian diet followed by an individual may reflect the motive to be vegetarian; motives for being vegetarian include, amongst others, ethical and ecological issues, health concerns, sensory and taste preferences and philosophical teachings. In addition to dietary choice patterns, vegetarians may differ from meat-eaters in a range oflifestyle behaviours: smoking habits, alcohol consumption, activity and leisure patterns and use of alternative therapies are all cited as examples. Furthermore, the body mass indices of vegetarians and vegans are typically 1–2 kg/m2 lower than matched omnivores. It is therefore important to remember this complex web of dietary and non-dietary differences when interpreting the results of studiescomparing vegetarians with meat-eaters, as such comparisons are not straightforward. In terms of nutrient intakes, the key nutritional issue for vegetarians and vegans is whether the nutrients supplied by meat and fish, in an omnivorous diet, can be provided in adequate amounts in foods that are acceptable to vegetarians and vegans. In the UK, for example, meat and meat products provide a majorcontribution to intakes of protein, iron, zinc, vitamin B12 and vitamin D. Conversely, compared with omnivorous diets, plant-based diets are reported to contain more folate, fibre, antioxidants, phytochemicals and carotenoids. Vegans, however, may have low intakes of vitamin B12, vitamin D, calcium and iodine. UK studies comparing lactoovo-vegetarians, vegans, fish-eaters and meat-eaters have shown that...