Losing belly fat overnight is not possible, but there are some drinks that can help in reducing belly fat over time. Here are some drinks that can aid in reducing belly fat:

1. Cinnamon and water: Cinnamon is known to help in burning belly fat. Boil a glass of water for about 10 minutes with a cinnamon stick or a pinch of cinnamon powder. Let it cool for a while till it becomes lukewarm. Add in honey to it and drink it on an empty stomach.

2. Green tea: Green tea is packed with antioxidants known as catechins that are believed to fight stubborn belly fat. Drinking green tea regularly helps in shrinking your belly. Catechins increase the release of fat from fat cells in the belly and also speed up the livers fat-burning ability.

3. Pineapple juice: Pineapple juice is believed to be a great remedy for belly fat. An important enzyme called bromelain which is found in the juice of pineapple helps in metabolizing protein and burns away excess stomach fat.

4. Peppermint tea: Peppermint tea helps in relieving bloating which can lead to belly fat. It acts as a natural diuretic and thus, prevents water retention by helping your body to flush out excess fluids.

5. Sabza water or chia seed water: Sabza ke daaney, or chia seeds, can help to reduce belly fat. Soak a tablespoon of chia seeds in a glass of water overnight. You can also have it an hour before meals. Chia seeds are rich in fiber and help in keeping you full for longer, thus reducing your calorie intake.

It is important to note that these drinks alone cannot help in losing belly fat. A well-balanced diet and regular exercise are also necessary for effective weight loss.