Presentation on theme: "An EPIC undertaking Lessons for vegetarians and vegans from the EPIC-Oxford study Paul Appleby September 2008."— Presentation transcript:
An EPIC undertaking Lessons for vegetarians and vegans from the EPIC-Oxford study Paul Appleby September 2008
The European Prospective Investigation into Cancer and Nutrition (EPIC) Largest ever cohort study of diet and health 520,000 participants in 10 European countries Coordinated at the International Agency for Cancer Research (IARC, part of WHO) Investigating the relationships between diet, lifestyle and environmental factors and the incidence of cancer and other chronic diseases
EPIC: 520,000 men and women in 10 countries IARC LYON PARIS FLORENCE MILAN RAGUSA TURIN NAPLES BARCELONA OVIEDO GRANADA MURCIA PAMPLONA SAN SEBASTIAN CAMBRIDGE OXFORD BILTHOVEN UTRECHT ATHENS HEIDELBERG POTSDAM MALMÖ UMEÅ AARHUS COPENHAGEN TROMSØ Tromsø Umeå Malmö Aarhus Copenhagen Oxford Cambridge Potsdam Heidelberg Utrecht Bilthoven Paris (nationwide) Turin Milan Florence Naples Ragusa Oviedo San Sebastian Pamplona Murcia Granada Athens (nationwide)
EPIC-Oxford Recruitment throughout the UK Aim to recruit as many vegetarians as possible: through GPs for the general public, by post for vegetarians Participants: 65,500 diet group, basic characteristics 57,500 lifestyle and food frequency questionnaire (FFQ) 31,000 first 7-day food diary ( ) 19,200 blood sample ( ) 38,000 first follow-up questionnaire ( ) 31,600 second follow-up questionnaire ( ) 14,000 second 7-day food diary ( )
Diet groups For many analyses EPIC-Oxford participants have been divided into one of 4 diet groups. GroupMenWomenTotal Meat eaters 7,80026,10033,900 (52%) Fish eaters 1,700 8,40010,100 (15%) Vegetarians 4,20014,70018,900 (29%) Vegans 900 1,700 2,600 ( 4%) Total14,60050,90065,500 (Numbers rounded to the nearest 100)
Main findings from EPIC-Oxford to date lifestyle characteristics and nutrient intakes diet and body mass index / weight gain hypertension and blood pressure hormones and diet diet and fracture risk diet and cancer incidence diet and mortality miscellaneous
Selected lifestyle characteristics Women CharacteristicMeatFishVegVegan Median age Current smoker (%) University degree (%) Married (%) Men CharacteristicMeatFishVegVegan Median age Current smoker (%) University degree (%) Married (%)
Mean daily nutrient intakes for women NutrientMeatFishVegVgnDRV Energy (MJ) Carbohydrate (% E) Protein (% E) Total fat (% E) Saturated fat (% E) PUFA (% E) Dietary fibre (g NSP) Folate (µg) Vitamin B12 (µg) Calcium (mg) Iron (mg)
Mean daily nutrient intakes for men NutrientMeatFishVegVgnDRV Energy (MJ) Carbohydrate (% E) Protein (% E) Total fat (% E) Saturated fat (% E) PUFA (% E) Dietary fibre (g NSP) Folate (µg) Vitamin B12 (µg) Calcium (mg) Iron (mg)
Davey et al, Public Health Nutrition 2003; 6: MenWomen
Mean annual weight gain (grams) during 5 years of follow-up by diet group Diet groupMenWomen Meat eater Fish eater377338*** Vegetarian Vegan284*303* Reverted Converted 2 242***301*** Means are adjusted for age at recruitment, smoking, physical activity, marital status, current paid job, age left school, and age at menarche in women. * / *** denotes significantly lower mean weight gain compared with meat eaters at the P<0.05 / P<0.001 significance level. 1 denotes subjects who changed their diet to include more animal foods during follow-up. 2 denotes subjects who changed their diet to include fewer animal foods during follow-up.
Prevalence of self-reported hypertension by diet group Women (% with self-reported hypertension) Adjusted forMeatFishVegVeganP Age alone <0.001 Age & BMI Men (% with self-reported hypertension) Adjusted forMeatFishVegVeganP Age alone <0.001 Age & BMI
Mean systolic blood pressure by diet group Women Adjusted forMeatFishVegVeganP Age alone <0.005 Age & BMI everything* Men Adjusted forMeatFishVegVeganP Age alone <0.005 Age & BMI everything* * - age, BMI, non-dietary factors, nutrient intakes
Self-reported fracture risk by diet group in EPIC-Oxford Diet groupIRR (95% CI) 1 IRR (95% CI) 2 Meat eaters1.00 (reference)1.00 (reference) Fish eaters1.01 ( )1.05 ( ) Vegetarians1.00 ( )1.02 ( ) Vegans1.30 ( )1.00 ( ) 1 Fracture incidence rate ratio compared with meat eaters among all participants, adjusted for age, sex and various non-dietary factors 2 As above, but restricted to participants consuming at least 525 mg/day calcium
Cancer in vegetarians: incidence rate ratios for vegetarians compared to non-vegetarians CancerCollaborative analysis of mortality, 1999 Latest results for cancer incidence, EPIC-Oxford DeathsDRRCancersIRR Colorectal ( ) ( ) Lung ( ) ( ) Breast ( ) ( ) Prostate ( ) ( ) All cancers ( ) All results adjusted for age, sex, smoking and study, as applicable: Key at al Am J Clin Nutr 1999, and unpublished 2008.
EPIC-Oxford: standardized mortality ratios as percentages, compared to UK national rates, among all participants aged below 90 with known diet group Cause of death DeathsNon- vegetarians VegetariansAll participants All circulatory (37-42)41 (36-47)40 (37-42) IHD46436 (33-40)34 (27-41)36 (33-39) Stroke25844 (38-51)54 (41-68)46 (41-52) All causes (45-49)48 (45-52)48 (46-49)
Mortality in EPIC-Oxford: deaths before age 90 among participants with no prior IHD, stroke or cancer Cause of deathDeathsDeath rate ratio for vegetarians versus non- vegetarians (95% CI)* IHD ( ) Stroke ( ) Total circulatory ( ) All causes of death ( ) *Adjusted for age, sex and smoking
Miscellaneous findings higher frequency of bowel movements among vegetarians and vegans compared with people who become vegetarian when adult, life-long vegetarians do not differ in adult height, weight, BMI or age at menarche in women
Selected Publications Allen NE, Appleby PN, Davey GK, Key TJ. Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men. British Journal of Cancer 2000; 83: Appleby PN, Davey GK, Key TJ. Hypertension and blood pressure among meat eaters, fish eaters, vegetarians and vegans in EPIC-Oxford. Public Health Nutrition 2002; 5: Davey GK, Spencer EA, Appleby PN, Allen NE, Knox KH, Key TJ. EPIC- Oxford: lifestyle characteristics and nutrient intakes in a cohort of meat- eaters and non meat-eaters in the UK. Public Health Nutrition 2003; 6: Spencer EA, Appleby PN, Davey GK, Key TJ. Diet and body mass index in EPIC-Oxford meat-eaters, fish-eaters, vegetarians and vegans. International Journal of Obesity 2003; 27: Key TJ, Appleby PN, Davey GK, Allen NE, Spencer EA, Travis RC. Mortality in British vegetarians: review and preliminary results from EPIC-Oxford. American Journal of Clinical Nutrition 2003; 78: 533S-538S. Appleby P, Roddam A, Allen E, Key T. Comparative fracture risk in vegetarians and non-vegetarians in EPIC-Oxford. European Journal of Clinical Nutrition 2007; 61:
Further information and acknowledgements EPIC-Oxford website: Thanks are owing to all participants in EPIC- Oxford, and to Professor Tim Key and colleagues past and present at the Cancer Epidemiology Unit, Oxford University. EPIC-Oxford is supported by Cancer Research UK, the Medical Research Council, and the European Community.