Ayurveda explains curd as having sour mixed sweet property and it increase Kapha Dosha in the body. The mucus generation is also attributed to the effect of Kapha. During night period, there is natural predominance of Kapha in the body. So, eating curd at night will further increase kapha leading to many complications.
This is quite similar to exposing yourself to hot Sun in the afternoon hours, which is not recommended, because, afternoon period is naturally Pitta Dosha dominant period and sun exposure also increases Pitta.
Qualities Of Curd According To Ayurveda
Amla paka rasam grahi guru ushnam dadhi vatajit |
meda shukra bala shleshma pitta rakta agni shopha krut ||
Curds is sour in taste, hot in potency, is heavy to digest (takes a longer period to undergo digestion). It increases fat, strength, kapha, pitta, digestive power.
Whenever there is swelling or inflammation, if curds is taken, it worsens the inflammation. Note that these properties are attributed to sour curds.
Naivaadyaa nishi naivoshnam vasantha ushna sharatsu na |
Sour curd should not be consumed by making it hot (ushna). Curds should not be consumed during night (nishi),It should also not be consumed during spring and summer seasons.
However, sour curds mixed with soup of green gram, honey, ghee , sugar and amla is helpful in relieving Dysurea (difficulty in urination) and indigestion.
Try avoid consuming curd at night. Because, night is basically Kapha predominant period. Thus consuming curd at night is best avoided according to Ayurveda.
If at all you are accustomed to take curd at night, I know that old habits die-hard. so, mix a small pinch of pepper powder to curds and consume. (do not add too much. it may cause burning sensation). You may also try adding fenugreek powder if you can tolerate a slight tinge of bitterness. (but this superb combination will relieve all kinds of stomach pain generated due to indigestion).
Mixing sugar and drinking curd at night is a strict no-no. Buttermilk is best substitute to curds at night. Buttermilk clears the channel and chucks mucus secretion.