As Salaamu Alaikum,
When fasting, is one allowed to use toothpaste if they are concerned with mouth odours when dealing with people that they work with?
Wa Alaikum As Salaam,
If one uses toothpaste while observing the fast, then there is the possibility that the toothpaste may go down the throat. If this happens, then the fast will be broken. It is for this reason, the scholars have stated that one should not use it while in the state of fasting. However, if you can make sure that this does not happen to you, then you can use toothpaste.
And Allah Knows best
Mufti Waseem Khan
This answer was collected from DarulUloomTT.net, which is operated under the supervision of Mufti Waseem Khan from Darul Uloom Trinidad and Tobago.