You have not explained which method you used to "load" the ".xls" file, but I am guessing you might have used the xlsread command to open a Microsoft Excel spreadsheet, and furthermore that you used the syntax:
As described in the documentation for xlsread, this will read "the first worksheet in the Microsoft® Excel® spreadsheet workbook named filename and returns the numeric data in a matrix." [emphasis added]
So, if that is the case, what you might want to try instead is the syntax:
[num, txt, raw] = xlsread(filename)
for which two additional variables are output from the function (or 'loaded' in your phrasing), namely txt and raw. The variable txt will contain the text fields in the form of a cell array, while raw will contain a mixture of numeric and text data, also in the form of a cell array.