Myths abound about drinking cold water after a meal. challenges the myth, popularized by viral e-mails, that cold water could cause cancer, finding no scientific backing for the claim. In 25 B.C., the writer Celsus asserted in “De Medicina” that drinking cold water right after a meal could aid digestion.

Modern western science finds no significant difference in the health effects of a glass of water after dinner or at any other time of day.

Water and Digestion

One rumor states that cold water could somehow solidify a meal’s oil into a hardened coating within your digestive tract. No scientific evidence supports the claim; the Mayo Clinic and Columbia University Health Services verify that this myth is untrue. On the contrary, drinking water immediately after a meal usually aids digestion. Water and other liquids help to break down solid food. If you want to improve your digestion, choose soups and large servings of water-rich foods like vegetables and fruits.

Daily Water Intake

If you enjoy having a glass of cold water after a meal, use it as part of your daily fluid intake. According to Mayo Clinic, most adults daily should have at least eight or nine cups of water. Basically, this is just more than two liters, assuming you derive about 20 percent of your water from food. Alternately, have eight 8-ounce glasses of water. If you tend to drink juices or beverages other than water, aim for nine to 13 cups of beverages per day. Exclude caffeinated beverages from your tally, as they actually have a dehydrating effect.

Cold Water to Lower Body Temperature

According to Columbia University Health Services, drinking cold water helps our bodies at certain points. If you’ve been training athletically, you may crave cold water to “cool down.” Having that bottle of water or sports drink may help. When the body’s core temperature rises above 98.6 degrees Fahrenheit, the body sweats to lower the temperature back to homeostasis, or internal stability. Drinking water at 41 degrees F can help to regulate your temperature while staving off dehydration. If cold water is unavailable, it’s better to have warm water than none at all.

Cold Water and Headaches

If you have a tendency for migraines or headaches, drinking water at room temperature may be advisable. A 2001 paper published in “Cephalalgia Journal” reported that drinking ice-cold water by straw resulted in headaches among women, particularly those who had experienced migraine symptoms during the preceding year. If you tend to develop migraines, drinking slightly warmer water or drinking directly from the glass may improve symptoms.