Resistant starch (RS) is defined as ‘the sum of starch and products of starch degradation not
absorbed in the small intestine of healthy individuals’. This basic definition includes different
types of starches that (1) are physically inaccessible, usually due to an encapsulation in intact
cell walls, or (2) are naturally highly resistant to mammalian α-amylase, or (3) have been modified
by hydrothermic treatments then retrograded. Interest in RS has increased significantly during
the last two decades, mostly due to its capacity to produce a large amount of butyrate all
along the colon. Butyrate has been observed to have a range of effects on cell metabolism, differentiation
and cell growth as well as inhibition of a variety of factors that underlie the initiation,
progression and growth of colon tumours. The physiological definition of RS, which seems
to be nearly consensual, raises a difficulty in proper analytical quantification of RS. A number of
methods have, however, been proposed and provide similar values for the RS content in most of
the starch types and starchy foods. It seems, however, that some starches, proven to be partly
resistant according to in vivo investigations on ileostomy subjects, could not be quantified by
most of these methods. This may be due to a widespread use of glucoamylase during the first
steps of these methods. Accordingly, there is an international debate on health aspects of RS and
on how to quantify the RS content of food products. The present review describes aspects of
classification of RS, past and current consumption, physiological effects and analytical aspects,
and concludes with impacts on food and product labelling.