Will cold water affect our throat / voice if we drink it before singing?
Also, in the long run (say if you drink cold water everyday), will cold water cause the throat / voice to be "lousy"?
Drinking cold water long-term won't make your voice "lousier". The whole idea behind singing is to have your vocal cords and surrounding muscles as loose as possible while singing. Hydration is a huge part of healthy vocal cords, so drink as much water as you can (hot, cold, or otherwise).
It's just recommended that if you get thirsty either just before or while singing that you drink room-temperature water.
The reason for this is because when muscles get cold they contract. Contracted muscles = tension. Therefore drinking cold water before or while singing causes your vocal cords to tense up and cause a "lousy" sound.
I think it always depends on the practice of the singer. Correct! Vocal cord needs to be hydrated and well loosed and drinking cold water contracts the muscles. But there is always an exemptions to the rules and as for me and my practice, drinking cold water helps me and my throat relax especially when performing. I've been singing since i was 5 and now i'm 32 and biting ice cubes is a practice to help me sing nicely. But again i would like to give emphasis on the line "it all depends with what you are practicing.
I have been singing since I was 12 years old and I am 50 now. I have never had a problem with any temperature of water. The point is to hydrate and drinking ice water is hydration. There are too many myths and witches tales taboos and rigidity when it comes to singing. I think the focus needs to be on technique and warming the vocal folds up adequately and allowing the fluidity and agility to come forth. I do think however that mixing it up a bit is important too. The voice is a delicate instrument and the focus on proper bel canto singing allowing the sound low larynx not pushed or pressed as well as overall working the instrument with balance and effortless sound should be the aim. Focusing on the temperature of water is a way of not focusing on technique.
Drinking cold water might not directly impact your vocal chords, but it can cause a sore throat, which is definitely not going to help your singing:
...having cold food items can increase your chances of suffering from sore throat. This happens because cold foods cause congestion of the respiratory mucosa. Respiratory mucosa is a protective layer covering the respiratory lining or tissue, which acts as defense mechanism against infections. When this mucosa gets congested (or shrinks) it exposes the respiratory lining to possible infectious agents, making it easier for viruses and bacteria to attack it and cause infections leading to a sore throat.
Apart from that, when you drink cold beverages during the summer it is more so capable of leading to an infection. This is because in the summers we tend to drink larger amounts of cold beverages, leading to a constant attack on the respiratory system. These infections also take a while to clear up because most people crave and drink cold drinks even though they are ill, delaying the entire healing process.
I lived in a very warm, dry climate for several years and drinking very cold water on a very hot, dry afternoon commonly resulted in a sore throat. It was common knowledge there that doing so was to be avoided.
If it's very hot, I'd think that a sudden change in temperature could also damage the delicate vocal chords.