Sections of human hair from naturally desiccated Sudanese Nubian mummies representing X-Group (AD 350–550) and Christian (AD 550–1300) periods in the Wadi Halfa area were analysed by Journal of Archaeological Science, 20 (1993) 657. These data can be interpreted in terms of a model of annual variation of food consumption that apparently remained stable for more than 1000 years. The diet oscillated annually between consumption of 75% C 3foods (wheat and barley) in winter, to as much as 75% of C 4foods (millet and sorghum) in the summer. There was little use of stored summer foods in the winter, whereas a small amount (c. 25%) of winter foods were present in the summer diet; part of this may be a carry-over in the form of a C 3isotopic signal in the flesh of C 3-fed animals. This evidently small use of stored grains suggests that grain storage facilities (granaries) were largely used as emergency measures. During normal years, the diet in a given season was dominated by freshly harvested crops.