...the international sales of cognition-enhancing supplements exceeded US$1 billion in 2015 and the global demand for these compounds is still growing rapidly...
Noma kunjalo, ukuthengiswa kwamazwe ngamazwe okuphazamisa ukukhushulwa kwe-cognition kudlule i-US $ 1 billion ku-2015 futhi isidingo somhlaba wonke salezi zinhlanganisela sisakhula ngokushesha.