Influence of days of the week on reported food, macronutrient and alcohol intake among an adult population in south western Finland

Objective: To study the influence of the days of the week on calculated foo d and nutrient intake. Study design: Daily variation in food and nutrient intake was studied by us ing 4-, 5- and 7-d estimated food records, all including Friday, Saturday a nd Sunday. Subjects and setting: Two groups of untreated hypertensive patients (60 men and 31 women, aged 31-55 y, and 132 men and 94 women, aged 35-54 y) and a random population sample of 131 men and 139 women, aged 35-64 y, all from t he City of Turku and three neighbouring municipalities in south western Fin land. Results: The intakes of meat and meat products, carbohydrate, alcohol and e nergy varied significantly across the week in all study groups with increas ed intakes of meat and meat products an Saturday and Sunday, of carbohydrat e and alcohol on Friday and Saturday, and of energy on Friday, Saturday and Sunday. Food and nutrient intakes did not vary consistently with weekdays (Monday to Thursday) with the exception of alcohol intake being lowest on M onday. Macronutrient, alcohol and energy intake data calculated from the 5- d (Monday, Tuesday, Friday, Saturday and Sunday) and from 5 to 7d converted food records were nearly equal to and correlated highly (r = 0.96-0.98) wi th the data calculated from the 'true' 7 d retards. Conclusion: The dairy variation in food and nutrient intakes should be take n into consideration when food diaries are recorded. 5-d food records inclu ding two weekdays (from Monday to Thursday) and Friday, Saturday and Sunday is recommended.