The literature reviewed has been divided into two sections, 1) where energy intake has been measured (table 1), and 2) where energy expenditure has been measured (table 2). Also, to permit some systematic analysis of the data, an arrangement based mostly on a progression by age has been adopted; i. e. through preschool children, those of school age, adolescents and young adults (up to 18–20 y of age), adults, and then elderly people. Males and females have been treated separately. Finally there is a separate category for pregnant and lactating women.
The published information on energy intake and expenditure of adult population groups have been divided into the occupational categories of the previous FAO/WHO report, i. e. 1) light activity work, 2) moderately active work and 3) very active occupations. Whether or not this is the best or even a desirable arrangement is discussed briefly later in this article.
The division was performed on the basis of the reported job denomination and of the description provided by the authors of the conditions under which the activities were carried out. A noticeable degree of guess-work has been necessary because the FAO/WHO occupational categories as well as the authors' description leave a wide lee-way to subjective interpretation.
All farmers (except for one group of agricultural labourers) were classified as moderately active.
Agricultural activities undergo seasonal cycles and there are times of the year when energy expenditure of the farmers may be reduced at levels which would fall within the ‘light intensity’ category, as in the post-harvest season or in winter, while at other times, during the peak of the agricultural season, they may more appropriately be classified in the ‘very active’ category. This appears to be particularly true for agriculture labourers, since they may go through an unemployment stage after the busy period of the agricultural year has finished.