1
Water
Biol 135 Lecture:
VI. Structure, Function and Source of Micronutrients.
A. Water
Water is Essential and the Basis to Life
Water makes up 60 to 70% of the human body at any given time. Structures within the body contain significant water. For example, blood is 83% water; the liver is 86% water; muscleis composed of 75% water; even fat is up to 20 percent water.Every component of the human body demonstrates the predominance and importance of water.Individuals will have varying percentages of water. In general, men have a slightly higher body % of waterthan women;young children, infants and athletes have a highercompositioncompared with sedentary adults or older individuals.
Molecular Structure of Water
The water molecule is H2O. It is composed of 1 Oxygen atom making covalent bonds with 2 Hydrogens atoms. These are polar covalent bonds, because the oxygen is more electronegative than the hydrogen and pulls the electrons closer to it, ‘having’ them more often that then hydrogen. This is what “polarizes” the molecule, that is, creates a sidedness to this molecule. There is a slightly negative pole and a slightly positive pole (see below). This has significant implications on the properties of water and how water interacts with itself and other molecules.
Figure 1. The water molecule is composed of an Oxygen atom and two Hydrogens atoms. An important quality of water is its ability to form hydrogens bonds with itself.
In terms of understanding the human body, it is important to know two basic categories ofmolecules:Polar and Non-polar. Water is polar and other polar molecules will easily dissolve in it. Non-polar molecules will not be as soluble in water.
Figure 2. The polarity of the water molecule gives it a sidedness in terms of electrical charge.
The Many Functions of Water in the Body
Since our body is about 70%water, it is the most abundant single component of the body! As such, it is involved in every aspect of how our body functions and the most significant way we get our water is through our diet. Outlined briefly below are some general functions of water in the human body.
Transportation
The blood that travels through our blood vessels and the lymph in lymphatic vessels is the primary way that substances are moved throughout our body. The transportation of nutrients throughout the body occurs based predominantly on what is dissolved in the plasma - the watery portion of blood. The plasma also transports the gases O2, and CO2around the body and hormones to and from cells.
List of Substances Dissolved in Plasma
Water is necessary in order to remove the waste products normally generated by your body. Referred to as ‘metabolic wastes’. We always need to lose some water in the processes of excretionof fluid waste that occurs in the kidneys called Urine and solid waste generated by the gastrointestinal tract called Feces.
Water plays an important role in the Digestionof nutrients in the body. Water is required for the breakdown (Hydrolysis) of the 3 organic macronutrients that are energy yielding.
Water helps to maintainstable body temperature (Tb)–It is especially crucial for the regulation of Cooling the body down!
Water is an important Lubricant for many areas of the body that are either heavily used (like joints, internal body cavities and muscles) or exposed to the outside environment:
•Joints
•Internal Body Cavities
•Eyes
•Mouth and Gastrointestinal Tract
•Lungs
•Urogenital Tract
ProtectiveCushion
Water anywhere in the body provides an insulative cushion that protects us against physical trauma. Also, in Pregnancy, the fetus is surrounded by watery amniotic fluid and this offers protection and insulation.
Water provides the Structure to Cells – the intracellular fluid (inside the cell) and the extracellular fluid (outside the cell) are mostly water and contribute to the shape and structure of all cells in the body.Water also provides structure and bulk to muscle cells, for example. This is especially true under the influence of a carbohydrate-loading diet and the generous storage of glycogen in muscle cells.
The 4 Properties of Water are:
1) Solvency – the Universal Solvent.
2) Cohesion – has a high affinity for itself.
3) Thermostability – has a very stable temperature.
4) Reactivity – participates in chemical reactions in the body.
Water is a Universal Solventand Transport medium. It is a polar molecule and many things can make H-bonds with it and dissolve in solution. It contributes to the dissolving of particles, digestion, and nutrient and waste transportation.The polarity of water attracts charged particles and dissolves other polar substances, including proteins, glucose, and many minerals.The water in blood allows for the transportation of oxygen (O2), nutrients, and hormones to all cells in the body. Since everything we eat and absorb goes into our blood stream, the types of food we eat will have a significant impact on the water in our body. Water is essential to maintaining acid-base balance in the body, and the various foods that we eat will also have an impact on the pH of our body fluids (which of course are mostly water).
Water Helps Maintain Body Temperature
Heat is absorbed in the body’s internal core and carried to the skin for release.Water has a high heat capacity (specific heat), allowing it to absorb and hold heat longer with little change in temperature.
Waterhas a High Heat Capacity: This means it takes a lot of heat energy to change the temperature of water.
Waterhas a High Heat of Vaporization: This means when water goes from a liquid to a gas, it takes a lot of heat energy with it.
When our internal body temperature rises higher due to physical activity or other factors, the increased heat breaks down hydrogen bonds, transforming the water from sweat to vapor, releasing the heat and further cooling the body. As we know, when water goes from a liquid to a vapor form it takes a lot of heat energy with it and leave you cooler.
The watery fluids, like the tears in your eyes and the saliva in your mouth are ~ 95% water, but they also contain oils, proteins and antimicrobial agents (like lysozymes). Interestingly, human milk and mucus have significant water and also contain antimicrobial agents and immunoglobbins to protect us.
Water Participates in Chemical Reactions: Dehydration Synthesis (Condensation) and Hydrolysis Reactions.
The three energy yielding organic macronutrients that we eat - Carbohydrates, Lipids and Proteins – all require water to hydrolyzetheir covalent bonds that hold these molecules together. This occurs during digestion.As the body uses ingested nutrients to make other molecules, water is pulled out of these molecules by dehydration synthesis.
When we consume polymers of any of these organic nutrients, they undergo Hydrolysis, this involves anaddition of a hydrogen ion to one molecule and a hydroxyl group to the other end of the newly formed molecule. This releases the energy stored in the chemical bonds as the nutrient is metabolized.When our bodies are combining smaller molecules to make a larger, more complex molecule, it does so removing a water molecule is from every bond that is formed when adding more ‘pieces’ to the larger molecule. Energy is being stored in the new covalent bonds that are made through this process calledDehydration Synthesis.
Water plays a role in Acid-Base Balance
Because water is polar, it can be used to decrease or increase pH levels by either breaking down or forming carbonic acid. That is, it can act as either an acid or a base.
What is the body's pH?
As we know, water is the most abundant compound in the human body. The various compartments of the body have different ranges of pH’s, depending on their primary function, some may be more or less acid.
The term pH means “potential of Hydrogen” it is actually a measure of the [H+] (reads: hydrogen ion concentration) in a fluid by taking the negative of the logarithmic scale! This is done so that the numbers are not 0.000001 but are between 0 and 14 and are easy to compare.
The higher the pH reading, the more alkaline (or basic) and oxygenrich the fluid is.
The lower the pH reading, the more acidic and oxygen deprived the fluid is.
The pH range is from 0 to 14, with 7.0 being neutral. Anything above 7.0 is alkaline, anything below 7.0 is considered acidic. Going up or down one number, say from 7 to 6, represents an order of magnitude difference, in other words the solution going from 7 to 6 just got 10 times more acidic! If it does to 5 it is now 100 times as acidic as the solution at 7.
The pH of human blood is slightly alkaline and should be within the range of 7.35 - 7.45. Below or above this range means unhealthy symptoms and disease. If blood pH moves below 6.8 or above 7.8, cells stop functioning completely and the body dies! The body therefore continually strives to balance pH.When this balance is compromised many problems can occur.
The most common imbalance in the American diet is a condition called acidosis, when the pH of our body fluids fall below the low end of that safe range. For example a blood pH of 7.30 creates a condition of metabolic acidosis, even though technically that value is still an alkaline solution (above 7.0), it is acidic as far as the homeostatic mechanisms of the human body are concerned and your systems will strive to get your pH back into the normal range (7.35 to 7.45).
A diet high in acidic-producing foods such as sugar, alcohol, highly processed foodsand high levels of caffeine (see Table 1) puts pressure on the body's regulating systems to maintain pH neutrality. The extra buffering required can deplete the body of alkaline minerals such as sodium, potassium, magnesium, and calcium, making the person prone to chronic and degenerative disease. Minerals are borrowed from vital organs and bones to buffer (neutralize) the acidic conditions and safely eliminatethe excess acids from the body. Because of this strain, the body can suffer severe and prolonged damage.
Health Problems Caused by Acidosis
Research shows that unless the body's pH level is slightly alkaline, the body cannot heal itself. So no matter what means you choose to take care of your health, it won't be effective until the pH level is balanced. If your body's pH is not balanced, for example, you cannot effectively assimilate vitamins, minerals and food supplements. Your body pH affects everything.
Acidosis will decrease the body's ability to absorbminerals and other nutrients, decrease the energy production in the cells, decrease its ability to repair damaged cells, decrease its ability to detoxify heavy metals, and make your body more susceptible to fatigue and illness. In addition, these kinds of conditions are ripe for caners and make tumor cells thrive.
Table 1. A general list of foods and their estimated Acid or Alkaline forming tendencies.
Strongly AcidicpH 4.0 / Mildly Acidic
pH 4.5 to 6.5 / Neutral
pH 7.0 / Mildly Alkaline
pH 7.5 to 9.5 / Strongly Alkaline
pH 10.0
White Bread, Processed Cheese / Meat and Fish,
Canned Fruits / De-ionized
Water / Many Fruits,
Coconut / Melon, Raisins,
Vegetable Juices
Alcohol, Beers / Legumes / Egg Yolks / Most Vegetables / Asparagus, Garlic
Sodas,
Tea, Coffee / Most Nuts / Raw Milk / Almonds / Cayenne Pepper
Cucumber
Sugar,
French Fries / Cooked Spinach / Raw Honey / Avocados / Raw Spinach
Kale
Peanuts, Walnuts / Brown Rice / Basmati Rice / Quinoa, Buckwheat / Kelp, Celery, Broccoli
Artificial Sweeteners / Dairy, Cocoa / Raw Cream, Whey / Falx Seed
Olive oil / Raw Swiss Chard
Note: There are various discrepancies between the acid- or alkaline-forming values given in the numerous lists provided by many websites and references. The table above is not to be taken as anything more than an approximate guide. We have many sources of informationat our fingertips and there are always likely to be errors or misconceptions in any format. From the many websites I’ve examined, the information compiled is like an amalgamation of the more common themes I have encountered. Many aspects are from sources that have cited personal experience and experience with clients, literally measuring body fluids with litmus paper before and after cleansing treatments. There has been a wealth of information gathered over time, much of which has not involved the scientific laboratory testing of isolated substances. This does not invalidate the positive results that can be seen in other types of studies. Often the physical, mental and spiritual transformation of an individual is quite a powerful piece of evidence.
The basic principles of good health seem remarkably clear: Eat Good Food.
Perhaps the issue for many people is that they may be uncertain as to what good food is. Could that be true? OR, is it that most people know what qualifies as good food but are unwilling to change the habits they have become accustomed to for most of their lives, regardless of their state of health?
The point of a class like this one is to present the best type of information so that you can make informed decisions about what you eat. The best informationreally means the most accurate – that is, the closest to the actual truth. The truth is often hiding in plain sight for all to see, if you are looking for it! Accurate information and thoughtful advice does not necessarily come from the big “trusted” icons of health, those amazing experts who would like you to believe that they know more than you do and onlythey know what is best for you. Strangely enough, finding the truth can sometimes come from your own experience. The best piece of advice I can give anyone is to dig deep and examine as much material as you can about a topic in nutrition that interests you. Be open-minded about what you might find, as it may be contrary to everything you have ever heard! Read carefully the many scientific and highly regarded studies that are out there to be found when it comes to any issue that is not in agreement with ‘conventional wisdom’. Often it takes quite a while for the real,truthful information to gain acceptance. This is partly because any ‘myth’ that is repeated over and over and over has become a belief for many (even regardless if it is a lie), and some people do not want to change their minds about anything! The other reason may be that many entities have a vested interest in the lie being perpetuated. That is, many actually benefit by others being poorly informed and making poor decisions about their health. They gain from your sickness – pretty terrible huh!? If you know the truth and still want to eat “Froot Loops” for breakfast, knock yourself out! The number one ingredient is sugar plus a host of artificial flavors and colors; notice the word Fruit is not used for a reason, no fruit item has come within a mile of that box – and they don’t want to lie to you after all! However, if you don’t want to be a victim, then educate yourself, it’s really not that hard to do. Examine all the information with an open mind and positive attitude and do not be afraid to go with your intuition – especially if you have practiced the art of trusting it!
So here is some truth about the good food to eat.
Eat whole foods. Basically anything that comes right out of the ground and you can eat directly!What this means is that a good diet that will keep you healthy should contain a significant portion of fresh organic vegetables and some fruit daily. Try not to eat too manygrain products, keep to whole grain and especially avoid the refined grains – that is, like the ones found in most breakfast cereals. They can be almost as bad as that highly addictive toxic substance called Sugar! If you know that your body does well with dairy products, then see if you can incorporate some raw dairy, like raw milk and raw cheese. It is highly nutritious because without the high temperature of pasteurization many more of the vital nutrients are retained to benefit you. Getting high quality protein directlyfromeggs, meat and fish is also recommended. If you are vegetarian, there are many nutrient dense whole grains (like quinoa, brown rice and buckwheat) legumes and nuts and many other viable options. Vegans (who do not eat any animal products) will need to take supplements, as there are several essential nutrients that your body must have to function optimally that can only be obtained from animals.