It is said that 'Long time drinking of ice-cold drinks can cause a lot of health problems, such as over weight, cough, headache, stomach problems, weak immunity, infertility etc.' and the reason is:
The average normal body temperature is 98.6°F (37°C). The ice drinks will bring down the temperature and slow down the energy and blood circulation inside the body. The coldness can be stuck somewhere in the body due to constant ice water intake, this will cause energy blockage. If the blockage occurs in the lower abdomen (which often happens to females), where uterus and ovaries are, many female related diseases and problems could appear including infertility and aging faster.
If the energy circulation slows, the metabolism slows, over weight is the result of that.
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A cup of ice water may make you feel heavenly after a sweaty exercise or at the time you feel really hot. But that cup of water could hurt you 10 times more due to the sudden cooling inside your body especially if you quickly finish it.
According to Ayurveda, ice cold water or drinks hinder the process of digestion and slow down the Jatharagni (digestive fire). As a result, food is not digested properly, leading to the formation of sticky toxic material (ama) in the small intestine. Other effects include under nourishment and blockage of body's channels (srotas), which can further lead to hundreds of diseases.
Ice cold water is very bad for patients because their digestive fire is already weak due to low levels of immunity.
According to Ayurveda, you should always drink water at normal room temperature. If you live in very hot climate, you can drink slightly cool water. And the best is to drink lukewarm water. It helps in enhancing the process of digestion, clears the accumulated toxins, opens up the blocked channels, and balances Vata and Kapha (Ayurvedic humours representing Air and Water). If you are suffering from Pitta diseases (such as skin rashes, burning sensation, hyperacidity, etc.),
There is an urban legend that if you drink cold water, especially after eating, you’ll get cancer. The theory, which has been widely circulated via email, suggests that cold water solidifies fats you have just consumed, quickly causing toxins to create cancer in your body. Sites devoted to proving or disproving urban legends, like snopes.com, have defeated this theory quite effectively.
Useful links:
* A discussion at a health forum: Is ice water bad for u?