Nutrients are only useful if the body absorbs them. The nutrition industry is full of apocryphal stories of vitamin pills that fill septic tanks after passing undigested through the body. Bioavailability measures how well nutrients are assimilated into the body. Some nutrients are relatively easy to assimilate, while others are notoriously difficult.
Herbs and spices have been used since ancient times for their ability to enhance the flavor and enjoyment of foods, and to preserve foods for storage and later consumption. However, herbalists know certain herbs and spices can also aid proper digestion, and increase the bioavailability of other nutrients. We are just beginning to understand how some of these herbal medicines work. Many spices show great promise as bioavailability enhancers, helping the body properly absorb and make use of other nutrients.