  Consumption of food in excess of the required optimal nutritional
requirements has already resulted in a global crisis and this is from the
perspective of human health, such as obesity, as well as food waste and
sustainability. In order to minimize the impact of these issues, there is a
need to develop novel innovative and effective solutions that can optimally
match the food consumption to the demand. This requires accurate understanding
of the food digestion dynamics and its impact on each individual's
physiological characteristics. This study proposes a model to characterize
digestive system dynamics by using concepts from the field of Molecular
Communications (MC), and this includes integrating advection-diffusion and
reaction mechanisms and its role in characterizing the digestion process as a
communication system. The model is then used to explore starch digestion
dynamics by using communication system metrics such as delay and path loss. Our
simulations found that the long gastric emptying time increases the delay in
starch digestion and in turn the glucose production and absorption into the
blood stream. At the same time, the enzyme activity on the hydrolyzed starch
directly impacts the path loss, as higher reaction rates and lower half
saturation concentration of starch results in lower path loss. Our work can
lead to provide insights formulated for each individuals by creating a digital
twin digestion model
