Combined impact of healthy lifestyle factors on colorectal cancer: a large European cohort study

Table 1 Description and prevalences of the factors comprising the Healthy Lifestyle Index (HLI), the EPIC Cohort (1992 to 2010)

Lifestyle factor	Index points	Description	Prevalence in the EPIC study population (%)
Lifestyle factor	Index points	Description	Men	Women	Overall
Overweight and obesity ^a	0	Overweight or obese: BMI ≥25 kg/m² or waist circumference ≥94 cm for men and ≥80 cm for women
	1	Healthy weight: BMI 18 to 25 kg/m² or waist circumference <94 for men cm and <80 for women	52.2	62.1	58.6
Physical activity ^b	0	Low and very low physical activity: sedentary or standing occupation and recreational METs ≤57 for men and METs ≤82 for women
	1	High and very high physical activity: manual or heavy manual occupation and recreational METs >57 for men and METs >82 for women	50.3	52.6	51.7
Smoking	0	Smoking: current smokers
	1	Non-smoking: never or former smokers	69.1	79.8	76.1
Alcohol consumption	0	Heavy alcohol consumption: not adherent to alcohol consumption recommendations of WCRF/AICR (2007) [15] for two standard drinks a day (>24 g/day) for men and one standard drink a day (>12 g/day) for women
	1	Limited alcohol consumption: adherent to alcohol consumption recommendations of WCRF/AICR (2007) [15],[16] for two standard drinks a day (≤24 g/day) for men and one standard drink a day (≤12 g/day) for women	66.0	75.9	72.4
Diet quality ^c	0	Unhealthy diet quality: 0 to 4 points of the diet index of colorectal cancer related foods
	1	Healthy diet quality: 5 to 8 points of the diet index of colorectal cancer related foods	60.9	59.6	60.1

^aBased on the World Health Organisation’s standard cutoff point for overweight [27] or waist circumference <80 cm for women and <94 cm for men according to the European Group for the Study of Insulin Resistance (EGIR) recommendations for European populations [28]. ^bA MET is defined as the ratio of work metabolic rate to a standard metabolic rate of 1.0 (4.184 kJ) kg^-1 h^-1; 1 MET is considered a resting metabolic rate obtained during quiet sitting. The MET values assigned to the non-occupational data were 3.0 for walking, 6.0 for cycling, 4.0 for gardening, 6.0 for sports, 4.5 for home repair (do-it-yourself work), 3.0 for housework and 8.0 for stair climbing [13]. ^cHealthy diet was evaluated based on a dietary quality index including eight dietary factors (fruits, vegetables, red and processed meat, fibre, fish, nuts, garlic and yogurt), which were previously shown to be related to CRC overall and in the EPIC data [2]-[8],[11],[12],[38]-[40] (Additional file 2, Table S2). BMI, body mass index (calculated as weight in kilograms divided by height in squared metres); EPIC, European Prospective Investigation into Cancer and Nutrition; METs , metabolic equivalents of energy expenditure (MET)-hours per week per year; WCRF/AICR, World Cancer Research Fund/American Institute for Cancer Research.

ISSN: 1741-7015