In blog post of 9/29/2014: So, what should you eat for optimal health?, I listed the seven basic principles I have extracted from the many diet books and resources I have studied. These principles are:
- What you eat, how much you eat and when you eat, all matter
- Eat clean
- Eat lots of vegetables and fruits
- Use only healthy fats and fat sources
- Incorporate sufficient proteins in your diet
- Best beverage to drink is pure water
- Add or subtract specific foods based on your personal needs
In the last posts, we discussed the first five of these principles. Today, let’s focus on the fifth principle: Best beverage to drink is pure water. And, as usual without any fluff stuff, let’s get to it.
I am sure by now you have heard over and over again, “Keep yourself hydrated.” Or “Drink plenty of water”. But why do we need to keep hydrated?
Water is the solvent for biochemical reactions and has unique physical properties (e.g., high specific heat) to absorb metabolic heat within the body.
Water is also essential for maintaining vascular volume and serves as the medium for transport within the body by supplying nutrients and removing waste. In addition, cell hydration has been has been suggested to be an important signal to regulate cell metabolism and gene expression.
Water is the largest component of human bodies. About 70% of our body weight is water. To maintain homeostasis, i.e., equilibrium in our biology, we need to replenish the daily water loss. Water loss comes from breathing out, sweating, urination and excretion.
You may have noticed feeling sluggish if you are dehydrated. In fact dehydration can bring on a variety of symptoms:
Mild to moderate dehydration is likely to cause:
- Dry, sticky mouth
- Sleepiness or tiredness — children are likely to be less active than usual
- Thirst
- Decreased urine output
- No wet diapers for three hours for infants
- Few or no tears when crying
- Dry skin
- Headache
- Constipation
- Dizziness or lightheadedness
Severe dehydration, a medical emergency, can cause:
- Extreme thirst
- Extreme fussiness or sleepiness in infants and children; irritability and confusion in adults
- Very dry mouth, skin and mucous membranes
- Little or no urination — any urine that is produced will be darker than normal
- Sunken eyes
- Shriveled and dry skin that lacks elasticity and doesn’t “bounce back” when pinched into a fold
- In infants, sunken fontanels — the soft spots on the top of a baby’s head
- Low blood pressure
- Rapid heartbeat
- Rapid breathing
- No tears when crying
- Fever
- In the most serious cases, delirium or unconsciousness
Many diseases are linked to dehydration. These include kidney stones, gall stones, bladder, colon and other cancers, arrhythmias, blood clots, Mitral Valve Prolapse, and Osteoporosis.
How much water do we need?
So, given that we need to keep body hydrated, that is, replace the H2O we lose daily with equivalent amount of H2O, how much water do we need everyday?
Institute of Medicine of the National Academies report on Dietary Reference Intake for Water, Potassium, Sodium, Chloride and Sulfate recommends the following DAILY Recommended intakes for water for different age groups:
For Children
1–3 years 1.3 L total; 0.9 L (4 cups) as beverages
4–8 years 1.7 L total; 1.2 L (5 cups) as beverages
For Males
9–13 years 2.4 L total; 1.8 L (8 cups) as beverages
14–18 years 3.3 L total; 2.6 L (11 cups) as beverages
Over 19 years 3.7 L total; 3.0 L (13 cups) as beverages
For Females
9–13 years 2.1 L/day of total water; 1.6 L (7 cups)
14–18 years 2.3 L/day of total water; 1.8 L (8 cups)
Over 19 years 2.7 L total; 2.2 L (9 cups) as beverages
Pregnant and Lactating women are exception and will need even more for each respective age group.
Can you drink too much water?
In very unusual circumstances, excess consumption of water and low sodium intake may lead to excess body water, resulting in hyponatremia and cellular edema. This condition comes from body getting too low in sodium rather than too much water.
What are the sources for water?
So, given that we need to keep body hydrated, that is replace the H2O we lose daily with equivalent amount of H2O, where do we get it from and where should we get it from?
Well first of all we do get a little bit of it when the body oxidizes hydrogen-containing substances during metabolism or energy production cycle. This water, called Metabolic Water is generally enough to offset the water we breathe out as vapors.
Rest of the water comes from what we consume, i.e., the stuff that crosses our lips. Of course, if you are taking nutrients intravenously (as saline solution or glucose solution in a hospital) that also counts.
All foods, especially, fruits and vegetables contain water. Beverages Coffees, tea, ice tea, milk, sodas, juices, beer all contain water. Institute of Medicine of the National Academies report on Dietary Reference Intake for Water, Potassium, Sodium, Chloride and Sulfate has the following table on daily water intake from a 2,200 calories daily diet. (Please click on the graphic below if it is not readable)
NOTE: This diet meets the Adequate Intake or the Recommended Dietary Allowance for adult men and women for all nutrients for which one has been established (for fiber, it meets the ratio of 14 g/1,000 kcal) and provides energy nutrients within the acceptable macronutrient distribution ranges. Nutrient totals may not equal the sum of the parts, due to rounding. Vegetables prepared without salt.
Food composition data: U.S. Department of Agriculture, Agricultural Research Service, Nutrient Database for Standard Reference, Release 16.
DATA SOURCE: ENVIRON International
So, what is the optimal source of hydration?
When I came to the US, 37 years ago, I somehow created associations that beer is the only drink that really goes with pizza and at McDonald’s you always ate hamburger with French fries and Coke. I don’t know how those associations happened, since I did not eat pizzas or McDonald’s’ hamburgers before coming to the US. I guess it was from watching all those TV commercials or just mimicking what everyone else around me was doing. In fact, it was four years later that watching a friend of mine, I learned that you could actually ask for water at McDonalds.
Fruits and vegetables are definitely good sources for water. Other than getting water from food, what about beverages? Are all beverages, coffees, tea, ice tea, milk, sodas, juices, beer, and wine as good a source of water?
Given the western culture, the answer could be quite confusing.
In research literature, there seems to be some controversy about whether coffee and alcohol are only transitional diuretics or permanent diuretics. Some say that caffeine and alcohol actually cause dehydration. Others disagree.
And, the citrus industry convinced us over two decades ago that “orange juice is not just for breakfast anymore”, so we should be drinking that all day long.
Coke and Pepsi, of course, promise us sex and happiness.
“Got Milk” teaches us that all the hip people drink milk and it is a fun drink and of course, it is the only source of calcium out there.
Beer is the real beverage to quench thirst, besides it gets us sex and popularity.
Wine is definitely one for sophisticated people and of course makes us live longer.
All this just to get people to drink their stuff to get hydrated! So, what is one to do?
I tend to agree with Joe Dillon, who likes to say, “Just because it is wet, does not mean it will hydrate you.”
Bottom Line
My take on all this is to ask the basic question: when I drink a beverage for hydration, do I want the collateral stuff?
Whether it is caffeine, or alcohol, or sugars or artificial sweeteners, or artificial colors, or whatever else, if I do want the collateral stuff, then the particular beverage at that moment is an acceptable, desirable or even a good source of hydration. If not, I rather just drink water.
And, in most of the situations, when I am looking to hydrate myself, I rather go directly to the source of hydration that my body is ultimately looking for, which, of course, is Water.
What do you think of this approach?
Do you feel that this simplifies the confusion about water and hydration?
Do you see a hole in this approach? What would you do differently?
Purposely Live to120 
Nice timing on this post, my friend and I were actually having a discussion on this very topic just the other day. She often gets dizzy during yoga when coming up from a pose that requires your head below your heart. When seeking advice from the teacher after class, among other remedies, hydration was mentioned.
We talked for a while about how she finds hydrating difficult because she doesn’t like the taste of water. This lead to a further discussion about whether the water in other beverages are as good of a source, and we were unable to settle on a clear answer. You bring up a lot of points that touch upon the subject, but still seems to offer inconclusive evidence.
At the end of our discussion, our solution was for my friend to start drinking water infused with flavors from things like lemons, oranges, cucumber and mint (thus adding a more pleasurable taste while keeping collateral to a minimum). It’d be interesting to learn more about that particular aspect of water.
Justin – Thank you for your very thoughtful comments.
Just to clarify, my conclusion is that water in other beverages is good or not good is based on weather the “collateral” stuff that comes along with that beverage is desirable or undesirable.
In my post, I only mentioned of examples of “collateral” stuff in beverages being undesirable. Infused waters is an example when “collateral” stuff is good. When you mix lemon, orange, cucumber or mint, it only enhances the water – may be more desirable taste and may be even some extra vitamins and minerals.
On another thought, you may want to remind your friend not to hold her breath while in that specific yoga posture (or any other posture for that matter) and continue to breathe . Holding breath can also lead to dizziness.
A friend sent his comment via email that I think is worth sharing:
I eat about 4-5 pieces of fruit in a normal day, but I’m pretty sure that I don’t drink enough water to reach the “standard” requirement.
Doing better with that, i.e., drinking more water-and doing more resistance training are two health areas where I have the most room for improvement
My response:
Here are a few helpful hints that I use to make sure I drink enough water:
1. Every once in a while, I actually count at the end of the day how many ounces I drank that day. And, see how it compares with what I need.
2. We bought a box of two dozen Nalgene water bottles. So, they are always with me: in my car, on my desk, in the plane, when we go walking, etc.
3. Justin’s comment above is good one: His friend decided she will enhance the taste of water and drink infused water instead. Many people use that that trick for better hydration.
4. When in cars or in our plane for long distance travel, water with slice of lemon or lime actually stays in the system much longer and you don’t have to stop for bathrooms as frequently.
5. I have rituals for drinking water. For example, first thing in the morning I drink a glass of water.
Hope these hints in keeping well hydrated.