The data set contains 8 files in total; it is two files (glucose and insulin data) for each meal type (standard, high carbohydrate, high fat, high protein).

The full description of data is available from references [26] and [27]. The two references are the following:

F. Q. Nuttall, M. C. Gannon, J. L. Wald, and M. Ahmed, "Plasma glucose and insulin profiles in normal subjects ingesting diets of varying carbohydrate, fat, and protein content," J Am Coll Nutr, vol. 4, pp. 437-50, 1985.

M. Ahmed, M. C. Gannon, and F. Q. Nuttall, "Postprandial plasma glucose, insulin, glucagon and triglyceride responses to a standard diet in normal subjects," Diabetologia, vol. 12, pp. 61-7, 1976. 

The paper describing the data from standard meal is the 1976 paper. Nuttall et al. Additional data on the other meal types and comparisons with all meal (including the standard meal) are in the 1985 paper.