Objectives: To (a) examine participation rate as a function of municipality, age group and living status; and (b) investigate the main reasons for exclusion and declining as stated by the women themselves. Design: Analysis of participation rate and content analysis of statements given in phone calls explaining exclusion or declination from a project in which 24 h recalls and food-diaries were used. Subjects: Self-managing Swedish women (n ¼ 505) were systematically selected from a stratified random sample covering single living and cohabiting women aged 64 -68, 74 -78 and 84 -88 y living in three municipalities. Results: No significant differences were found among included and declining women when municipalities and living status was analysed, but significantly more women in the oldest group were excluded (P > 0.01). Among those in their 80s living at home, the usual reasons for exclusion were illness, disability or dementia, and many lived in institutions for old people. The four most used explanations to decline participation were 'lack of time', 'tired, fragile, sick or having bad memory', 'not willing to participate in scientific studies' and 'too old and nothing to contribute'. Conclusions: The participation rate was, compared with other food surveys in the older generation, fairly good, especially among those in their 80s. However, the most active and the very ill and disabled did not participate.