No, it is not part of the Sunnah.

Is it Sunnah to eat something sweet after lunch or dinner?

Fasting | March 30, 2014 10:26 am
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Does smelling an extremely foul smell invalidate the fast,or if the fasting person has to stay in a stingy environment for a while does it have any impact on the validity of his fast?

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I wish to allah keep stronger and long lives for you shiekh… one of my friend telling me, for all men are not allowed to fasting on the first day of sawal. isn’t that true?