Mark Murphy, from The Irish Heart Foundation, refuted the suggestion.
If you can vote at 18 you should be allowed to buy cigarettes.
Speaking on Kildare Today, John Mallon, of the tobacco-funded lobby group Forest Ireland, said 18-year-olds are adults and should be treated as such.
Refuting Mr Mallon's claims, Mark Murphy, from The Irish Heart Foundation, said restricting cigarette sales to 21-year-olds has been shown to reduce smoking rates among teenagers.

New Appeals System For Asylum Seekers Comes Into Effect
Bord Bia Review Published In Light Of Controversy Surrounding Brazilian Beef Importation
KCC Report Reveals North Vs South Divide In Kildare
Kildare TD Highlights Difficulties Faced By Wheelchair Users In Curragh School
"A Fall Every Week" : Mayor Of Naas Calls For Alterations To Kilcullen Road
Local TD Accepts Data Centres Are A "Particular Issue" In Ireland
Kildare Dog Shortlisted For Bravest Pet Award
Kildare Senior Football Team vs Kerry