Nutrition & Wellness
Nutrition is the science of food – the way the body ingests, digests, absorbs, transports, utilizes and excretes food. It is the process of nourishing your body with all the essentials it requires to thrive on a daily basis.
Just as exercise influences body weight,so does the nutritional value of foods. Nutrition is the one factor that can make or break the attainment of your weight loss goal, yet it is often overlooked.
Therefore, to get the most from the foods you eat; you should know:
- What nutrients your body needs in order to maintain optimal health and fitness.
- How these nutrients function.
- Which foods contain these nutrients.
- Changes you can make in your lifestyle and eating habits to achieve weight loss.
There are three types of macronutrients that your body needs to maintain health: carbohydrates, protein, and fat. Water is sometimes considered a fourth macronutrient since it is so vitally important. Vitamins and minerals are referred to as micronutrients, and are needed to assist the enzymes in our body. The function of these basic nutrients is described in the upcoming segments.
Remember: A healthy lifestyle is not about deprivation. It’s about setting reasonable expectations for yourself and having pride in your body and yourself, so that you can live life vigorously.
When it comes to weight loss, slow and steady wins the race. The most the body can lose in actual fat in a week is about 2 lbs. (almost 1 kg). So be happy with losing “only” one or two pounds a week! It is the only safe and effective way to lose weight – and keep it off. If you are not sure if you are overweight, check the Body Mass Index.
Our bodies work extremely hard to convert the food we eat into something useful. In fact, 70% of the energy our bodies produce each day goes into digesting our food. This is the task of the digestive system.
The digestive system begins in the mouth and ends at the anus. It is divided into several parts starting with the mouth, esophagus, stomach, small intestine and large intestine. The liver, pancreas and gallbladder are also part of the digestive system. Together they perform four main functions:
- Ingestion – the intake of food
- Digestion – the chemical breakdown of food into usable molecules
- Absorption – movement of usable (nutrient) molecules into the blood stream.
- Elimination – removal of solid waste products.
Friendly bacteria in our bowel help to fend off disease-causing organisms such as salmonella by producing natural antibiotics. These beneficial bacteria feed on undigested carbohydrates, producing lactic acid which helps keep other organisms such as yeast in check. Other important functions include:
- synthesizing vitamin K, and the B vitamins biotin and pantothenic acid
- synthesizing chemicals which heal the bowel lining and help prevent cancer
- synthesizing acetic acid which keeps the liver from making too much cholesterol
- helping to break down toxic environmental chemicals
The number of bacteria in our bowel can weigh a total of three pounds! Only certain bacteria are suitable residents, however. The type of bacteria that take up residence in our bowel depends to a great degree on the type of food we eat. Fibre-rich foods such as whole grains, legumes and fresh fruits and vegetables help to promote healthy populations of friendly bacteria and discourage harmful strains. Foods made with lactobacilli cultures such as yogurt help replenish supplies of beneficial bacteria. A diet high in refined foods such as white flour and white sugar attracts bacteria that produce large amounts of foul gases and other by-products that can irritate the bowel lining.
Carbohydrates are composed of only three elements – carbon, hydrogen and oxygen. When they are broken down, they produce large amounts of energy.
Without this energy, legs could not walk, the brain could not create and calculate, lungs could not inhale and exhale and the heart could not beat. Carbohydrates produce 4 calories for every gram.
A Clean-Burning Fuel
Carbohydrates are an abundant, easily obtained and clean burning fuel source, and therefore our primary fuel. There are three basic types:
Monosaccharides, like most families, have certain characteristics in common. They consist of only one single sugar. They are crystalline, dissolve easily in water, taste sweet, and are absorbed directly into the bloodstream from the digestive tract. Glucose and fructose are examples of single sugars that our digestive system can absorb. Ribose and deoxyribose are monosaccharides that are essential components of our genetic molecules Ribonucleic Acid (RNA) and Deoxyribonucleic Acid (DNA). Glucose is the sugar required in greatest quantity by the body, and most of that is used by the brain. Glucose can be utilized in three different ways:
- It can be “burned” for energy.
- It can be stored in small quantities as glycogen in muscle and liver cells.
- It can be changed to fat and stored in fatty tissues to serve as an energy bank.
While glucose may be the most important monosaccharide, fructose – which is found in fruits and honey – tastes the sweetest. It is also absorbed much more slowly from the digestive tract than glucose. Galactose, or milk sugar, is produced in breast milk.
How Sweet It Is
The next branch on our carbohydrate family tree is the disaccharides, which are formed by joining two monosaccharides together.
Disaccharides, like their simpler cousins, are crystalline, easily dissolved in water, and sweet to the taste. However, these double sugars cannot be absorbed by the digestive tract. To be useful in our bodies, disaccharides must first be split by specific enzymes into their component monosaccharides.
When glucose and fructose are joined together, the disaccharide formed is sucrose, or common table sugar. Sucrose is found in large quantities in beets and sugar cane. Lactose, the sugar associated with milk products, is a disaccharide formed from glucose and galactose. The enzyme required to split lactose is called lactase. People who lack this enzyme are unable to digest dairy products.
Both monosaccharides and disaccharides are referred to as simple sugars. These sugars are found in a wide variety of refined foods, under an equally wide variety of names. Corn syrup, invert sugar, corn sugar, sorbitol, levulose, dextrose and fructose are all aliases for simple sugars.
The Complex Cousin
The last branch on our carbohydrate family tree is the polysaccharides, carbohydrates with three or more sugar molecules linked together. Most naturally occurring carbohydrates come in this form. When compared to their monosaccharide and disaccharide cousins, this family group exhibits very different characteristics.
Polysaccharides are powdery instead of crystalline, they are too large to dissolve in water, and they are not sweet to the taste! Cornstarch is an example.
Starch, glycogen and fibre are the most common polysaccharides. They are called complex carbohydrates because of their large, branching structures.
Starch is a plant polysaccharide made up of hundreds and even thousands of individual sugar molecules linked together in long branching chains much like an intricate Indian bead design. This type of carbohydrate is found in grains, beans, peas, potatoes, squash and other vegetables.
In order to be absorbed, each of the hundreds or thousands of single sugars making up the starch molecule must be broken off, one by one, by the proper enzymes. For this reason, starch provides a slow but steady supply of sugar to the blood.
Glycogen is a polysaccharide made by animals. When we consume more carbohydrate then we need for energy, the liver converts the excess to glycogen for storage. Glycogen is a very large molecule, and may contain up to 10,000 glucose sugars linked in long chains. Muscle cells also store glycogen.
Between the liver and muscle, approximately 425 g, not quite one pound, of glycogen is stored in the body. This is a relatively small energy bank, so it must be continually renewed through the food supply.
During exercise or when we skip a meal, glycogen is broken down to glucose to provide a source of quick energy.
Five kinds of plant polysaccharides fall under the label of fibre. They are cellulose, hemicellulose, lignins, pectins and gums.
Fibre is not a nutrient because we do not have the enzymes necessary to break it down and absorb it. However, it is an essential component of a good diet and provides many health benefits.
Cellulose, hemicellulose, and lignins are not soluble in water and are called insoluble fibre or roughage. Wheat bran that you use to make bran muffins contains this kind of fibre. Pectins and gums are water soluble fibre found in oats, flaxseed, apples and other foods. Together they aid the digestive system by moving stool through the large intestine more quickly and binding toxins, thereby limiting the time they can be in contact with the intestinal wall. Soluble fibres bind cholesterol in the gut, preventing it from being reabsorbed and making it easier to excrete in the stool. This action can actually lower blood cholesterol levels.
Carbohydrates run our engine and we need a steady supply every day if we want to perform our best. Eating a variety of whole foods such as whole grain breads and cereals, pasta (whole grain), fresh fruits and vegetables, and peas and beans helps keep blood sugar levels steady and ensures an adequate supply of fibre.
Whole foods supply both the carbohydrates we need, and all the nutrients required to metabolize them. They protect us from “nutrient debt” caused by eating foods stripped of fibre, vitamins and minerals. Limiting the use of simple sugars and refined white flours can help prevent hypoglycemia. That means reducing intake of table sugar, many processed breakfast cereals, soft drinks, candies, cakes, cookies and white breads.
Proteins provide the building material for the growth, maintenance and repair of all body tissues. They function as enzymes, hormones, antibodies and hemoglobin to carry oxygen.
Maintenance of water and acid-base balance in the body are other important functions.
Proteins give shape and strength to living things. Hair and nails are made of protein, and within our cells, protein strands provide shape and structure.
Proteins even help hold us upright! Bones are composed of calcium and phosphorus embedded in a protein lattice work, while a special protein called collagen makes up most of our connective tissues – it keeps our complexions, tendons and ligaments strong and supple.
Proteins are instrumental in the growth, maintenance, and repair of all tissues. When you cut your finger, the proteins fibrin and thrombin help your blood clot to stop the bleeding. If bacteria enter the wound, then antibodies – special proteins formed by the immune system – attack these invaders. Then, to speed healing, new skin cells are formed under the scab.
Perhaps the cut looks quite deep, and you have to head to the emergency room for stitches. While waiting, you grab a candy bar from the vending machine. The refined sugar in the candy bar causes a rapid rise in your blood glucose, triggering a release of insulin from your pancreas.
Insulin, a protein hormone, “unlocks” the doors to the cells and lets in the glucose, where it can be used for energy. How fast your body is able to break down food is decided by yet other protein hormones made in the thyroid gland!
There are many more proteins with specialized functions. Muscle fibres can contract because of unique proteins that respond to electrical impulses. Some proteins control the balance of water, acidity and salt levels in the blood. And most of us are familiar with hemoglobin, a red protein that makes up most of red blood cells and carries oxygen to every cell in the body.
Proteins can be used for energy when carbohydrates or fats are scarce, but produce byproducts that the body must detoxify and eliminate.
Carbohydrates and fats are composed only of carbon, hydrogen and oxygen, and are used to provide energy. Proteins contain nitrogen as well, and can be “burned” for energy when carbohydrates and fats are scarce. One gram of protein provides the same amount of heat energy as one gram of carbohydrates – 4 calories.
When proteins are burned for energy, the nitrogen forms ammonia, a toxic by-product that must be converted to urea by the liver. Urea must then be eliminated from the body by the kidneys.
You can see why the body prefers to use carbohydrates or fats for energy–they are clean-burning fuels!
Proteins are extremely large, complex molecules whose shape is essential to biological function.
Proteins are able to perform so many varied functions because of their unique composition and structure. Just as large starch molecules are made up of many single sugars joined together, proteins are made up of many small organic molecules called amino acids linked together in chains.
Many proteins have thousands of amino acids in their sequence. With even one amino acid out of sequence, the protein cannot properly perform its job.
Essential Amino Acids
Humans use about 20 different amino acids, combined in a vast variety of ways, to construct all the different proteins required by our bodies. The body is able to formulate 12 of the 20 amino acids used to make proteins, but eight of them (10 in infants) cannot be manufactured and must be obtained in food. These are called essential amino acids because they are essential for health.
The basic unit of protein structure is the amino acid. All amino acids contain carbon, hydrogen, oxygen and nitrogen. Human proteins are manufactured using 20 different amino acids, eight of which adults must obtain from our food supply. Both plant and animal foods can supply all the essential amino acids.
The body is only able to store excess carbohydrates and fats – not protein. Fortunately, plant and animal foods are able to supply us with a steady source of the essential amino acids that make up protein. This is very important because there is constant protein destruction in the body, so we must continually replenish the supply of essential amino acids.
Foods containing all the essential amino acids are labeled “complete proteins,” while foods providing only some of the essential amino acids are called “incomplete proteins.”
COMPLETE PROTEINS: Eggs, fish, dairy products, meat, and poultry provide complete, good quality protein. However, they are high in saturated fats and cholesterol, and completely lacking in carbohydrates and fibre.
INCOMPLETE PROTEINS: Grains and legumes are incomplete proteins. Generally, grains lack the essential amino acid lysine, and legumes lack methionine.
Alone, grains and legumes are incomplete proteins, but eaten together their amino-acid profiles complement each other to provide complete protein. Grains supply the methionine that legumes lack, and legumes can supply the lysine that’s missing in grains.
Grains such as brown rice, corn, whole wheat, millet, quinoa and legumes such as peas, beans and lentils are excellent sources of protein when eaten together. Depending on the method of preparation, these foods are very low in saturated fats and cholesterol.
There are many benefits to the traditional pairings of beans and rice, tortillas and beans, and pitas with hummus. These complementary proteins provide both carbohydrates and protein, a wide variety of vitamins and minerals, and fibre.
Fats are lipids. These compounds tend to be oily or waxy, and are not soluble in water. They include:
- fats, which tend to be solid
- oils, which are liquid
- and cholesterol
Gram for gram, fats produce slightly more than double the amount of energy that carbohydrates produce. Lightweight and energy dense, fat burns slowly and gives off an enormous amount of heat energy. Every gram of fat burned creates 9 calories of heat energy.
If people stored all their energy reserves in carbohydrates, our bodies would be much larger than they are! That is because fats contain no water in their molecules, whereas carbs are carbon plus water.
Think of diving into a pool with your clothes and running shoes still on. Those clothes seemed to weigh nothing when dry but are an enormous burden when wet! Glycogen, the storage form of carbohydrates, is much bulkier than fat.
Besides storing energy, fats, cholesterol and other lipids perform many vital functions. Cholesterol is the chemical backbone for sex hormones such as estrogen and testosterone, anti-inflammatory hormones such as cortisol, and bile needed for fat digestion. The layer of fat under the skin provides a thermal blanket for the body much like the insulation in your attic. Fats are also required for the absorption and storage of the fat-soluble vitamins, A, D, E and K. People who consume extremely low fat diets may be susceptible to deficiencies in these vitamins. Fats are responsible for the particular mouth feel and flavour of many foods. They also contribute to a feeling of fullness, a signal to stop eating.
After energy storage, the most critical role that fats play is in the formation of cellular membranes. All the membranes in the cell are composed mainly of compound fats called phospholipids and cholesterol. These membranes are the site for energy production within the cell and protein production. They also serve as the gatekeepers for the entry of nutrients and the exit of toxic wastes. Phospholipids are also involved in blood-clotting.
Saturated and Unsaturated Fats
Fats are composed of fatty acids joined to a small molecule called glycerol. Each glycerol molecule can hold up to three fatty acids. When it contains three fatty acids it is called a triglyceride. Fat is stored in our body in the form of triglycerides. Your doctor may decide to measure the amount of triglycerides in your blood when you go for a physical examination. Fatty acids are straight chains of carbon atoms. The chains can be anywhere from 4 to 22 carbon atoms long. Saturated fatty acids, the ones you should limit in your diet, contain as many hydrogen atoms as the carbons can hold on to. In other words, the carbon chain is saturated with hydrogen. If any of those hydrogen atoms are removed, the fatty acid becomes unsaturated.
One double bond in a fatty acid makes it monounsaturated. More than one and it is polyunsaturated. Olive oil is monounsaturated oil and corn oil is polyunsaturated. Saturated fats are very stable, do not change when heated, and do not easily go rancid. Unsaturated fatty acids are vulnerable to attack by heat, light, moisture and air. Most of the fats found in foods have a combination of saturated and unsaturated fatty acids. The fats of animals are mostly saturated. Saturated fats are found in beef, pork, dairy products, lamb, and chicken.
Vegetable oils that have been hydrogenated, or hardened, to create shortening and most margarines, are saturated. Hydrogenation creates trans fats, which are not made by the body and have no known health benefits. These unsaturated fats have been straightened out at the double bonds. By altering the essential shape of the molecules, trans fats are biologically inactive, and detrimental to health. They act more like saturated fats, sticking to artery walls. Plants tend to have unsaturated fats with the exception of tropical oils. Since palm and coconut trees are exposed to extreme heat, humidity, and intense sunlight in their tropical setting – all conditions that can damage double bonds – nature gave them saturated fats without double bonds!
Although tropical oils are saturated, they contain medium-chain fatty acids and micronutrients that support well being. Their major fatty acids are used for energy nearly as quickly as sugars, and are less likely to be stored as fat. You can probably find 100% palm oil at your local health food store, labeled as “trans-fat free, organic shortening.”
Essential Fatty Acids
If most of the fats in our bodies are saturated fats, then why are we told to limit saturated fats and eat unsaturated fats instead?
Humans can manufacture all but two of the fatty acids our bodies require, using excess carbohydrates and protein. These two fatty acids, linoleic acid and linoleic acid, are called Essential Fatty Acids (EFAs) because they are essential to health and must be obtained from the diet. Both are polyunsaturated and found in plant foods. Once again we are dependent on plants for essential nutrients. Good sources are whole grains, seeds, nuts, dried beans, and dark green leafy vegetables.
Polyunsaturated oils pressed from corn, sunflower, sesame, soybean and flaxseed are potentially excellent sources of EFAs. Unfortunately, once these oils are pressed, they are very perishable. For example, whole flax seeds can be safely stored in a cool, dry place for up to one year, but flax oil must be refrigerated in a dark container and used within two weeks of opening.
To extract seed oils and prevent spoilage, food processors put cooking oils through an extensive process of heating, bleaching and deodorizing. To ensure a nutritious product, look for cold-pressed polyunsaturated oils. Do not use these oils for cooking. Keep them refrigerated in dark containers. They make excellent oils for salad dressings. For cooking, monounsaturated, cold-pressed extra virgin olive oil is a delicious and healthy choice. The best advice – get your EFAs (essential fatty acids) from whole foods. Eating rancid or altered fats is worse than eating saturated fats.
The Cholesterol Conundrum
There are two sources of this waxy-like substance – the cholesterol we consume in our diet, obtained only in animal products, and the cholesterol produced by the liver. Cholesterol is essential for good health yet we are bombarded by news about its health hazards. High levels of blood cholesterol are a serious risk factor in heart disease and stroke. Then we’re told there is “good cholesterol” and “bad cholesterol.”
Our brains do not work very well without cholesterol. And without cholesterol, our body cannot make several hormones, bile for digestion or cell membranes. Since cholesterol and triglycerides are not soluble in the watery medium of the blood, they are transported by a class of compounds called lipoproteins, which prevents them from floating to the surface like the oil in an oil and vinegar salad dressing.
There are different types of lipoproteins. All contain cholesterol and triglycerides at the centre and an outer coating of protein and phospholipid to make them soluble. They differ in the amounts of these components. HDL (high density lipoprotein), or the “good cholesterol” contains the most protein and the least cholesterol and triglyceride. LDL (low density lipoprotein) or “bad cholesterol” contains comparatively more cholesterol and triglyceride and less protein.
To help yourself remember which is better, think of keeping your “LDL Low” (low because it’s the bad one) and “HDL High” (high because it’s the good one). LDL cholesterol carries cholesterol and triglycerides to the cells to produce hormones or energy or membranes, etc. Unfortunately, LDL cholesterol seems to have a greater tendency to attach to artery walls, contributing to arteriosclerosis, or hardening of the arteries. About 50% of all cholesterol is transported by LDL. HDL cholesterol acts in the opposite direction, picking cholesterol up from artery walls and returning it to the liver. There it is incorporated into bile, and begins its journey out of the body through the intestinal tract. As you can see, both types of cholesterol are necessary to good health, but like everything else in nature, it is the balance that is important.
Cholesterol & Saturated Fats–the Connection
Diets high in saturated fats and cholesterol have been associated with increased risk of heart disease. Health authorities advise us to decrease the total amount of dietary fat, and especially cut down on saturated fats and cholesterol. What is the link when cholesterol contains no fatty acids at all, saturated or unsaturated, and in fact it is a completely different type of lipid?
There is a reason for the recommendation. A diet high in saturated fat seems to encourage the liver to produce more cholesterol internally. This leads to an increase in LDL or “bad cholesterol.” The Omega 3 oils in cold-water fish and some seed oils such as flaxseed or hemp oil seem to increase levels of HDL and decrease levels of LDL. Beware of products that advertise “cholesterol free.” They may still be very high in total fat, and if they contain hydrogenated vegetable oils, they may be high in trans fats too, which are detrimental to health.
|Vitamins and Minerals|
|Biotin||Phosphorus||Vitamin B6 (Pyridoxine)|
|Chlorine||Sodium||Vitamin B Complex|
|Copper||Vitamin A||Vitamin C|
|Folic Acid||Vitamin B1 (Thiamin)||Vitamin D|
|Iodine||Vitamin B2 (Riboflavin)||Vitamin E|
|Iron||Vitamin B3 (Niacinamide/Niacin)||Vitamin K|
|Magnesium||Vitamin B5 (Pantothenic Acid)||Zinc|
Vitamins and minerals assist the enzymes in our body. Without them, body processes would grind to a halt, which is why they are so vital to good health.
They are called “micronutrients” (micro means small) since the amounts in which we need them are so minute, they are measured in milligrams or micrograms. In contrast, a macronutrient such as protein is measured in grams.
Vitamins are either fat-soluble (vitamins A, D, E, K), which means they require some fat to be absorbed and are stored in the liver and fatty tissues of the body, or water-soluble (the B vitamins and vitamin C), which are not generally stored in the body and therefore need to be replaced daily, thus are less likely to cause toxicity than fat soluble vitamins.
Vitamin A – for healthy skin and eyes
Vitamin A is critical for normal vision, especially night vision, as well as the growth and formation of bones.
Healthy skin also depends on vitamin A. This includes our inner “skins” – the linings of the digestive, respiratory, and urinary tracts. Vitamin A keeps them soft, supple, and covered in protective mucus. Since these “skins” are the first physical barriers to bacteria and viruses, vitamin A helps prevent infections.
Foods provide us with two forms of vitamin A:
Preformed vitamin A is found in animal foods such as liver, butter, whole milk, fortified low-fat milk, and fish liver oils.
Beta-carotene, which is converted to vitamin A in the body, is found in plant foods such as dark orange vegetables and fruits (carrots, sweet potatoes, squash, apricots, mangoes) and dark green leafy vegetables (spinach, kale, collard greens).
Carotenes are a group of antioxidant pigments which act like shields, helping neutralize free radicals. Free radicals are unstable molecules that can be destructive to healthy cells in the body.
Vitamin D – the sunshine vitamin; for bone health
Vitamin D is needed for bone growth because it promotes calcium absorption, and helps
maintain mineral balance in the body. A deficiency results in rickets in children and osteomalacia in adults. These conditions are characterized by soft bones, which cause bowed legs and a curved spine.
Our bodies produce vitamin D when the ultraviolet rays of sunlight interact with the skin. However in high amounts, vitamin D is toxic. The symptoms associated with sun sickness – stomach cramps, nausea and vomiting – are actually signs of vitamin D toxicity.
Food sources include fortified milk, egg yolks, butter, cod liver oil, cold-water fish such as salmon, mackerel, and herring. Dark green leafy vegetables provide small amounts of vitamin D.
Vitamin E – the anti-sterility; antioxidant vitamin
In 1922, researchers noted that rats fed a diet devoid of vitamin E could not reproduce. Since then, vitamin E has been known as the fertility or anti-sterility vitamin. Tocopherol, the chemical name for vitamin E, literally means “to bear children.”
Vitamin E has powerful antioxidant properties, giving it the ability to protect cell membranes and its immune function. It becomes part of the fatty portion of cell membranes, protecting them from toxic metals, free radicals and other harmful compounds. In addition, it is vital to normal immune function, since it shields the thymus gland and white blood cells from damage.
There is growing evidence that vitamin E supplementation may help prevent heart disease by protecting artery walls from free-radical damage. It also acts as a natural blood thinner.
As a first-aid treatment, topically-applied vitamin E oil is very helpful for wounds, especially burns. It speeds healing and reduces scarring.
The best food sources of vitamin E are polyunsaturated vegetable oils. Fresh seeds and nuts, whole grains and cold-pressed, unprocessed vegetable oils are good sources of vitamin E. Dark green leafy vegetables, wheat germ and wheat germ oil, egg yolk, butter and liver are other sources. Processing of oils destroys most of their vitamin E.
Vitamin K – the clotting factor
When you cut your finger, vitamin K comes to the rescue, helping the body make several factors that make blood clot. Research indicates that vitamin K also helps hold calcium in place in the bones.
Beneficial bacteria in the large intestine produce vitamin K in amounts that can equal half of our daily need. Food such as dark green leafy vegetables and green tea are excellent sources of vitamin K. Asparagus, oats, whole wheat and fresh green peas are also good sources. It is interesting to note that most of the foods high in vitamin K are also high in calcium.
Vitamin C – For wound healing, collagen production and antioxidant
Numerous studies show that vitamin C increases the activity of white blood cells and antibodies that help us fight off bacteria and viruses.
Vitamin C is perhaps the most important antioxidant in the body. Where vitamin E protects the fatty components of the body, vitamin C protects all the watery areas of the body, both inside and outside the cells. In addition, it protects the fats circulating in the blood, especially so-called “bad” LDL cholesterol.
“C & E” work as a team. As soon as vitamin E neutralizes a free radical, it becomes inactive, and goes off duty. Vitamin C makes it functional again, and sends it back into action.
Collagen formation is vitamin C’s other key role. Collagen is the protein produced by all connective tissues for strength and support. It is found in virtually every tissue of the body, and forms the backbone for blood vessels, bones, teeth, tendons, skin and fatty tissue. People with scurvy, a disease caused by a deficiency of vitamin C, show bruising and bleeding gums as the first symptoms.
Vitamin C is needed to form neurotransmitters, chemical signals that transmit messages down a nerve fibre. It also helps prepare excess cholesterol for removal from the body, and is essential for the absorption of iron and folic acid (folacin) from the digestive tract.
Food sources include fruits and vegetables, especially citrus fruits, cantaloupe, strawberries, tomatoes, green peppers, dark green leafy vegetables, broccoli, potatoes, fresh peas and lettuce. Unfortunately, this wonder nutrient is easily lost in cooking water or when exposed to air, baking soda or antacids.
The B Complex – produce energy by breaking down carbohydrates, protein and fat
The B complex includes vitamins B1 (thiamin), B2 (riboflavin), B3 (niacin, niacinamide), B5 (pantothenic acid), B6 (pyridoxine), folic acid or folacin, B12 (cyanocobalamin) and biotin.
All the B complex vitamins act as enzyme helpers or coenzymes, most often in the pathways that break down food for energy. Many also aid normal nerve and brain function. Often the first signs of B vitamin deficiency are neurological, emotional and psychological in nature.
B1 (Thiamin) – release energy from carbohydrates
Vitamin B1, or thiamin, helps burn carbohydrates. A deficiency leads to beriberi, characterized by fatigue, depression, tingling or numbness in the legs and constipation. Untreated, beriberi can lead to permanent nervous-system damage. Mild B1 deficiency can produce these same symptoms, especially in the elderly.
Whole grains are a good source, as well as beef, organ meats, nuts, cooked and dried beans, milk, cauliflower, spinach provide some B1.
B2 (Riboflavin) – energy metabolism
This nutrient is essential for cell growth because it helps build fatty acids and amino acids and produces energy from glucose. A lack of B2 causes cracks at the corners of the mouth, an inflamed tongue, sensitivity to light, and cataracts.
Food sources include organ meats (liver, kidney, heart), milk products, almonds, mushrooms, whole grains, soybeans, and dark green leafy vegetables. This vitamin is destroyed by exposure to light but not by cooking temperatures.
B3 (Niacinamide/Niacin) – Energy metabolism and tissue formation
Vitamin B3, or niacin, a coenzyme takes part in more than 50 metabolic reactions, including the burning of fats and carbohydrates for energy, and the production of sex and adrenal-cortex hormones. A severe deficiency of niacin results in pellagra, a disease characterized by the “3Ds:” dermatitis, dementia and diarrhea.
B3 comes in two forms: niacin (nicotinic acid) and niacinamide. High doses of niacin can cause a temporary red flushing of the face called the “niacin flush.”
The body can make some niacin out of tryptophan, an amino acid. Rich sources of niacin and tryptophan include liver, eggs, fish and peanuts. Other sources of this vitamin include legumes, whole grains (except corn), milk and avocados.
B5 (Pantothenic Acid) – Energy metabolism and tissue formation
Like the other B vitamins, B5 helps extract energy from carbohydrates and fats. It is converted to coenzyme A in the body, which operates in carbohydrate, fat and protein metabolism, and also helps form red blood cells and the neurotransmitter acetylcholine, a chemical that sends messages from one nerve cell to another.
B5 is important in the formation of cell membrane components and special phospholipids needed by the brain. Since the adrenal gland is especially dependent on it, B5 is often called the “anti-stress” vitamin.
Fatigue, numbness and shooting pains in the feet are symptoms of pantothenic acid deficiency. A deficiency is rare because pantothenic acid is widely distributed in foods. Highest levels are found in organ meats, milk, fish, and poultry. Good plant sources include legumes, sweet potatoes, broccoli, cauliflower, oranges, strawberries and whole grains.
B6 (Pyridoxine) – Energy metabolism and tissue formation
Vitamin B6, or pyridoxine takes part in more than 60 chemical reactions. Because B6 is required for all cells to multiply, it is extremely important in maintaining a healthy pregnancy, good immune function, normal “lining” tissues and red blood cells.
B6 is vital to normal brain function because it helps produce many neurotransmitters, or chemical messengers. A lack of B6 can cause depression, convulsions, impaired nerve function, anemia and cracking of the lips and tongue. Pyridoxine shows some nerve toxicity at doses greater than 2,000 mg per day.
Meat, poultry, fish, egg yolks, soybeans and other legumes, bananas, seeds, nuts, potatoes, cauliflower and brussels sprouts are all sources of B6.
Folic acid (folacin) – Fetal development
Folic acid or folacin is converted to its active form in the body by niacin and vitamin C.
Folic acid has been shown to prevent certain birth defects. Folic acid is needed to manufacture DNA, so it is critical to cell division and the development of a fetus’s nervous system.
A deficiency of folic acid affects all cells, especially the ones with a quick turnover like red blood cells, and those lining the intestinal and genital tracts. Symptoms range from depression, irritability, forgetfulness, diarrhea, fatigue, poor growth and shortness of breath. Pernicious anemia is a hallmark of both folic acid and B12 deficiency.
Folic acid occurs widely in plant foods such as dark green leafy vegetables, legumes, asparagus, oranges, root vegetables and whole grains. It is easily destroyed by food processing, so eat some of your greens raw.
Vitamin B12 – Red blood cell formation
B12 has many of the same functions as folic acid, including DNA synthesis and red-blood-cell formation. In addition, B12 is necessary for the insulation, or myelin sheath, surrounding nerves. When this sheath is damaged, nerves cannot send messages properly.
As mentioned, a deficiency of either folate or B12 can lead to pernicious anemia, a disease showing large, immature red blood cells. If left untreated, pernicious anemia leads to irreversible nerve damage and madness.
B12 is found only in animal foods. Liver and kidney provide the highest amounts. Eggs, meat, cheese and fish have good quantities as well. Vegans, strict vegetarians who eat no animal products, should supplement with B12.
Biotin – Helps metabolize amino acids and carbohydrates
Biotin promotes strong nails and healthy hair. If your infant had cradle cap, it was probably due to a biotin deficiency. Biotin deficiency in adults causes dry, scaly skin, nausea and lack of appetite.
Biotin functions as four different coenzymes involved in breaking down glucose and fatty acids for energy. It is also required for cell growth and division. A good array of intestinal bacteria will produce biotin. A vegetarian diet attracts intestinal bacteria that produce more biotin and enhance its absorption.
Food sources include cheese, organ meats, soybeans, cauliflower, eggs, mushrooms, nuts, peanuts, and whole wheat.
These elements consist of two categories: major minerals (calcium, phosphorus, magnesium, potassium, sodium and chloride) and trace minerals, or trace elements (chromium, cobalt, copper, iodine, iron, manganese, selenium, zinc and many others).
When talking about minerals, it is important to understand the principle of synergy. Synergy says that each mineral influences the effect of all the other minerals. Each one is required in its proper amount for optimal function.
Nature has devised several methods to keep many minerals within proper limits in the body. The digestive tract will absorb more of a mineral in which the body is deficient. For instance, someone with iron-deficiency anemia will absorb more iron from their food. An excess of a mineral will be excreted through the kidneys or bowel.
Many minerals are kept in balance by being forced to compete with another mineral. Iron and copper, for example, are transported by a protein called transferrin. These two minerals compete for the limited amount of transferrin available.
Calcium – for strong bones and teeth
Calcium is the most abundant mineral in the body. In bones and teeth, calcium combines with phosphorus to form the crystalline structure that gives bone its strength. Calcium is needed for muscle contraction, the sending of nerve messages, activation of enzymes, blood clotting and maintenance of fluid balance.
A deficiency of calcium is one of the factors in rickets (see vitamin D) and the bone-thinning disease osteoporosis (brittle bones). Calcium by itself, however, will not build strong bones; calcium works in synergy with magnesium and vitamin D and will not be absorbed without its two partners. Many other minerals such as boron, manganese, copper, zinc and phosphorus, plus many vitamins such as the B complex, and protein, are needed to build bone. Hormones also influence bone density.
The best food sources of calcium include dairy products, canned fish such as salmon or sardines with the bones, and dark green leafy vegetables like kale and collard greens. Spinach is loaded with calcium but it is not well absorbed. Almonds, sunflower seeds, and fortified soy beverages are also good sources.
Magnesium – energy production and heart health
About 60% of the magnesium in your body is found in bone tissue; the remainder is in muscle (especially heart muscle) and soft tissues.
This mineral forms part of more than 300 enzymes. It is critical for the production of energy from food, the formation of DNA, muscle contraction and nerve impulses, protein synthesis, and the functioning of many hormones.
The best food sources of magnesium are whole grains and legumes, green leafy vegetables and sunflower seeds. More than 80% of the magnesium of grains is lost in refining and it is not added back when white flour is enriched. In addition, high levels of calcium intake can depress magnesium absorption.
Signs of magnesium deficiency include fatigue, confusion, muscle cramps, irritability, and heart disturbances. Low magnesium levels may increase the risk of heart disease, high blood pressure, kidney stones or menstrual cramps.
Phosphorus – works with calcium strengthening bones and teeth.
Phosphorus is a very versatile mineral and serves a wide variety of functions in the body. Most phosphorus is found in the bones, where it combines with calcium to give bones and teeth strength and rigidity. Phosphorus is a major component in DNA, RNA and cell membranes. It is also required for the growth, maintenance and repair of all tissues, and is necessary for protein synthesis. Phosphorus is the “P” in ATP (adenosine triphosphate), the cell’s preferred source of energy.
Most people consume twice the required amount of this mineral. While dairy products provide a very absorbable source of calcium, they are also very high in phosphorus. High intakes of phosphorus can cause calcium to be pulled from the bones, resulting in a net calcium loss.
Nutritious food sources include meats, fish, poultry, eggs and dairy products.
Sodium, Potassium and Chlorine – Maintain water balance
These three minerals are always discussed together because they function together as a system called electrolytes.
Electrolytes are charged particles called ions, and they will conduct electricity when dissolved in water. Electrolytes start the sparks flying that make our muscles contract and our nerves send messages.
Electrolytes always work in pairs: one negatively-charged ion pairs up with a positively-charged ion. Sodium and potassium are positive ions and they attract chlorine, which has a negative charge. Together, they control water flowing into and out of cells. These minerals also function to maintain water balance between cells and blood, acid-base balance in the blood, proper heart function, kidney and adrenal gland function.
The body functions best when it has more potassium than sodium. Most fruits and vegetables in their natural state have at least 50 times more potassium than sodium. Unfortunately, most people consume twice as much sodium as potassium. Sodium sneaks in during cooking, and by way of prepared foods, restaurant foods, condiments and salting food at the table.
Iron – Red blood cell formation
This mineral literally sits in the middle of the hemoglobin molecule in red blood cells, carrying life-giving oxygen to all the cells of the body. It also accepts the waste product carbon dioxide from tissues, returning it to the lungs to be exhaled. Iron also works with several enzymes involved with energy production and DNA synthesis.
Iron comes in two forms and is found in many foods.
Heme iron, which is found mainly in red meats and liver, is the most easily absorbed.
Non-heme iron is found in whole grains, sardines, dried fruits, dark green leafy vegetables, eggs, prune juice, oysters, and many other foods.
Unfortunately, the body finds it very difficult to absorb heme iron and even more difficult to absorb non-heme iron. High levels of calcium, fibre and antacids taken with iron-rich foods further inhibit absorption. Vitamin C enhances iron absorption, so grab a glass of orange juice with your raisins.
Iron deficiency is the most common nutrient deficiency in North America, with more women deficient than men. This causes impaired oxygen delivery to the tissues, leading to anemia, learning disabilities, decreased energy levels and excessive menstrual blood flow.
- aids collagen formation for healthy bones and connective tissue
- acts as a coenzyme in energy production and hemoglobin production
- forms copper superoxide dismutase, a powerful antioxidant enzyme
- helps form the myelin sheath, the protective covering surrounding nerves
- aids iron absorption
Copper deficiency leads to connective tissue and bone breakdown, brain disturbances, elevated levels of LDL (“bad”) cholesterol and decreased levels of HDL (“good’) cholesterol and reduced immune response.
Food sources include whole-grain breads and cereals, shellfish, nuts, eggs, poultry, dried beans and peas, and dark green leafy vegetables. Drinking water drawn from copper pipes provides some copper.
Zinc – for prostate gland, wound healing and immune function
Zinc is a component in more than 200 enzymes and performs a veritable encyclopedia of functions. It is necessary for protein synthesis, wound healing, immune function, insulin activity, prostate function, and a proper sense of taste, sight and smell. Zinc is also critical to the healthy production of sperm.
Oysters are the best food source of zinc, and other shellfish, fish and red meats provide it too. Plant sources include whole grains, legumes, nuts and seeds, although the zinc in plant foods is not well absorbed.
In adults, 55% to 65% of body weight is composed of water. In infants, the percentage rises to 75%. Virtually every body process depends on water, and every cell, tissue and body fluid contains water.
Composed of only one oxygen atom and two hydrogen atoms (H2O), water is an amazing substance.
How the Body Uses Water
If enzymes hold the keys to all our chemical reactions, then water is the medium where they all take place.
The blood, lymph fluid, digestive juices, urine, and perspiration are all mostly water. Gases and nutrients are carried in the watery medium of the blood.
Wastes are removed from the body in urine and stool which are mainly water. Even stool, which seems solid, is 70% water.
A flow of electricity is required for nerve impulses and muscle contraction. The minerals responsible for these electrical impulses require a water solution to send their messages.
The body uses water to maintain a constant body temperature because it takes a great deal of energy to raise the temperature of water. That’s why your internal body temperature remains at 37°C even when you are outside on the hottest summer day. Perspiration is the body’s refrigeration system. Water on the skin evaporates and releases heat from the body.
Water is essential to the build-up or breakdown of carbohydrates, proteins and fats. Every time an enzyme goes to break off a sugar, an amino acid or a fatty acid, a water molecule is needed to break the bonds. When our bodies build a protein, carbohydrate or triglyceride a water molecule is removed for every amino acid, simple sugar, or fatty acid that is added to the chain.
We must provide sufficient water for all metabolic processes, and replace water lost in urine (1.5L), feces (100-200 mL), sweat (500-700 mL), and water vapour in our exhaled breath (250-300 mL).
The normal sedentary adult requires six to eight 8-oz. glasses of water each day to maintain water balance. In hot weather and with increased activity, water requirements can increase five or six fold.
There are three sources of water: liquid drinks, food and metabolic processes.
Purified or spring water is the perfect drink to restore water balance. When exercising on a hot day, cold water with only small amounts of glucose or salts speeds the water through the stomach to the small intestine where it is absorbed and ready to help cool the body.
Fresh vegetables and fruits such as lettuce and tomatoes, oranges, watermelon, zucchini and cabbage have a high water content. That’s what makes salad or a juicy orange so appealing on a hot day. These foods are also low in calories.
When fats, proteins and carbohydrates are burned for energy, carbon dioxide and water are produced. A sedentary person derives approximately 350 mL of water from such daily metabolic processes.
Although we require a great amount of water daily and it is vital to life, water provides no direct nutritional value. In other words, water cannot produce energy, but energy cannot be produced without it!
Portions are the amounts of food we eat each day, while control can be defined as the activity of managing control over something – in this case our food.
So portion control is eating rationally and consuming adequate amounts of the appropriate foods.
And What Is An Appropriate Portion Size?
If you are able to follow Canada’s Food Guide and its recommendations, it can be simple. For adults, they recommend per day 6-8 servings of grains, 7-10 fruits and vegetables, 2-3 milk products and 2-3 meat and meat alternatives. The amount varies based on your age, sex, and physical activity.
Grains (breads, cereal, pasta and rice) — 1 slice of bread, 3/4 cup of cereal, 1/2 cup of cooked pasta or rice.
Fruits and vegetables — 1 medium sized fruit or vegetable, 1/2 cup vegetables or fruit, 1 cup of salad, 1/2 cup of fruit juice.
Milk products — 1 cup of milk, 3/4 cup of yogourt, 2 slices of cheese.
Meat and meat alternatives– 50-100 g or 2-4 oz of meat, poultry or fish, 1-2 eggs, 2 tablespoons of peanut butter.
When eating out at restaurants, portions are greatly exaggerated. Yes, we want to get what we pay for, but there is always room for leftovers. You can eat a portion, and save what you are not going to eat for lunch the next day. Or split your meal with a friend.
When shopping for groceries, read the labels. The serving size is listed on each label. Check to see if it’s reasonable for you.
Over time, portion control becomes easier. Just think before eating! There is no need to weigh your food, rather be conscious of the amount you are eating. Instead of multiple scoops of ice cream, enjoy just one scoop. When eating meat, a serving will be the size of the palm of your own hand (not your friend’s huge bear paw!), or a deck of cards. One medium sized fruit is the size of a tennis ball.
Be conscious of your health choices. What you eat is just as important as how much you eat. They go hand in hand.