Abernethy biscuit
The Abernethy biscuit was invented by doctor John Abernethy in the 18th century as a digestive improver and hence aid to health.
Abernethy believed that most diseases were due to disorders in digestion. The Abernethy biscuit is a type of digestive biscuit, a baked good originally designed to be eaten as a support to proper digestion. In creating his biscuit, Abernethy was following in the footsteps of other medical practitioners, including William Oliver of Bath, Somerset (invented the Bath Oliver) and American preacher come nutrition guru Sylvester Graham (invented the Graham cracker).