Water, how can something so simple be so complicated

I have been thinking a lot about water lately which might be due to the summer's high temperatures and trying to stay cool.   Our bodies are made up of 66% water and it plays a vital role in how our body functions.  Your brain is made up of 75% water, your blood 82% and your lungs nearly 90% plus your metabolism works better with proper hydration.  Dehydration causes the liver to help the kidney's function, interfering with fat metabolization creating fat retention.

The body adapts to chronic dehydration by storing water for emergencies, much like a camel, our bodies tend to store water in the hips, thighs and ankles.   Once you restore your body to a constant state of hydration it will release this water storage, if you are holding water then drinking more helps release it from your system.   Staying hydrated helps to cushion our joints, transport nutrients, regulate blood pressure, keeping skin hydrated, helps bowel function, reduces headaches, regulate body temperature and many other functions as well. That is a lot of information but that isn't what I found to be so confusing, it was the what, why and how of drinking water that started the thought process going for me.

While talking with a group of fitness people the conversation turned towards water.  I mentioned that I had read at one time that drinking tepid water was best for hydration, ice water was best for cooling the bodies core temperature but recently I had read that ice water has a negative impact on the esophagus and that some people drink ice water as the body burns calories warming it up.  Water is essential to our bodies, how are we supposed to know what is best for us if there is so much conflicting information out there.

• Discovery Health as a basic description of the ice water calorie burn information story "Does Drink Ice Water Burn Calories" which you can read.  According to the estimates from Discovery Health drinking eight 8 oz glasses of ice water will help burn 70 extra calories a day.  I do want to add that you should never put a water bottle in the freezer, this is old information that dates back to the 80's before people realized the leeching of chemicals from plastic bottles even existed.  
• Ice water changes the way the body digests foods and can worsen GERD according to Living with Gerd on their site I read this in the tips to avoid GERD: "consider ice cubes a very dangerous item on the table. Don't. Your stomach is temperature sensitive - when the temperature of the food is lower than body temperature everything will sit taking up space in the stomach until it all gets warmed up to body temp. That is, a dish of ice cream, a cold drink (even ice water) will stop your food from being digested. Increasing the risk that that stuff will still be there hours later when you sit down to your next snack or meal. Getting the 'freeze' under control was one of my bigger problems. Instead, drink water, decaffeinated green tea. ...Part of what makes soup a 'comfort food' is the warmth." 
• Finding information about the impact of ice water isn't easy on the internet as the web is flooded with posts about burning fat with ice water.  However I found this information from PubMed.gov which is the "US National Library of Medicine National Institute of Health."  Here I found a medical report on sudden death from ingesting ice cold liquids in patients with underlying heart disease. To read this click  link to the report however here is the content:  "We report a case of sudden cardiac death in a 12-year-old boy after rapid ingestion of a frozen slurry drink. The cause of death was determined to be a cardiac arrhythmia secondary to a previously undiagnosed cardiac rhabdomyoma with associated myocardial scarring. Ingestion of cold liquids has been associated with syncope, but not sudden cardiac death. In this case, bradycardia induced by cold-induced vasovagal reflex may have precipitated the terminal arrhythmia. Ingestion of cold liquids should be considered a potential trigger for fatal cardiac arrhythmias in patients with underlying heart disease."
• One more interesting report from San Diego’s personal trainers of holistic health page on Gastrointestinal Disorders reports that 50% of people over 65 have a lowered production of HCI digestive acid or hydrochloric stomach acid.  This condition is called hypochlorhydria and is not limited to people over 65, they list drinking liquids either to hot or ice cold included in the risk factors for the this condition.
  
  

I have asked a few random people about their experience with ice cold water and here is what I have found.  Some people love ice water and can't drink it any other way as they say it improves the taste and palatability.  Others have reported discomfort and difficulty in swallowing ice water and having it give them hiccups, pain in the chest and stomach discomfort.  While not easy to find the reports due to the sheer volume of reports on the weight loss from ice water there are cases where ice water can be a concern for people with underlying conditions like asthma, heart disease or digestive issues.  If you can tolerate ice water and prefer it then by all means drink it as you like but for proper food digestion and water absorption room temperature water appears to be your best option.

Side Note:
Drinking too much water is also a concern as you can dilute the electrolytes needed to keep your body running properly, this condition is called Hyponatremia.  Babies are at risk from this condition and so are athletes.  Athletes sweat heavily which causes them to lose both water and electrolytes at a rapid rate.  Ingesting water only and not replacing the accompanying electrolytes can cause the cells to burst due to an improper balance.  For the full explanation check it out here: Water Intoxication & Hyponatremia  Keeping in mind that unless you are in a water drinking contest it is hard to ingest the amount of water needed to cause death from Hyponatremia.  Of course there is coconut water, natures natural gatorade, drink that and skip the added sugars in processed sports drinks..