A<unk>  is a compound that has an effect on a living organism, tissue or cell. In the field of nutrition<unk> s are distinguished from essential nutrients. While nutrients are essential to the sustainability of a body, the<unk> s are not essential since the body can function properly without them, or because nutrients fulfil the same function.<unk> s can have an influence on health.
Bioactive compound
Chemical substance
Immunogen
Volatile organic compound
Generic drug
Pollutant
Biological agent
New chemical entity