Nutrition Explained

Macronutrients are the components of foods that provide calories (or energy) to the body. There are three main macronutrients:

➜ Carbohydrates ➜ Fats ➜ Proteins

Each of these macronutrients plays an essential role in how the body utilizes and stores energy for basic functions, activities of daily life, and more strenuous activities.

Micronutrients (absorbed) are the minute but essential amounts of elements in food that your body needs to sustain function and good health. Vitamins and minerals are examples of micronutrients.

Phytonutrients (phytochemicals, phytonutrients) are found in plant foods. These compounds appear to offer protective benefits against disease in humans. A number of compounds fall into the category of phytonutrients, including flavonoids, phenolic acids, lignans, and stilbenes.

The digestion and absorption of macronutrients (carbohydrates, lipids, proteins) and micronutrients (vitamins and minerals), essential for the requirements of the human body, take place mostly in the small intestine. In most cases digestion occurs both in the gastrointestinal lumen and at the mucosal surface, continuing in some cases within the enterocytes themselves. Substrate-specific enzyme processes exist for polysaccharide carbohydrates and polypeptides, linked with digest-specific active co-transporters to aid absorption at the cellular level. The hydrophobicity of fats makes lipid handling more complex, requiring the creation of intraluminal emulsions and micelles which present lipid degradation products to the enterocytes. The intestine (small bowel and colon) has additional mechanisms for absorption and re-absorption of water and key electrolytes. In most cases micronutrients are liberated from dietary macromolecules by non-specific digestion and then absorbed passively (or as other lipid-soluble moieties in the case of the fat-soluble vitamins) but some specific transporters are also involved as in the case of vitamin B12. Quantitatively minor but important digestion and nutrient absorption also occur in the colon. (src)

The body’s machinery to process food and turn it into nutrients is not only efficient but elegant.

The action unfolds in the digestive tract in two stages: ➜ digestion - the breaking apart of foods into smaller and smaller units ➜ absorption - the movement of those small units from the gut into the bloodstream or lymphatic system for circulation.

Your digestive system is designed to digest carbohydrates, proteins, and fats simultaneously, while at the same time preparing other substances (vitamins, minerals, and cholesterol) for absorption. Remarkably, your digestive system doesn’t need any help!

You probably wouldn’t eat a food if it didn’t appeal in some way to your senses. Smell and taste belong to our chemical sensing system, or the chemosenses. The complicated processes of smelling and tasting begin when tiny molecules released by the substances around us bind to receptors on special cells in the nose, mouth, or throat. These special sensory cells transmit messages through nerves to the brain, where specific smells or tastes are identified.

The Chemosenses

Olfactory (smell) cells are stimulated by the odors around us, such as the fragrance of a gardenia or the smell of bread baking. These nerve cells are found in a small patch of tissue high inside the nose, and they connect directly to the brain. Gustatory (taste) cells react to food and beverages. These surface cells in the mouth send taste information along their nerve fibers to the brain. The taste cells are clustered in the taste buds of the mouth and throat. Many of the visible small bumps on the tongue contain taste buds. A third chemosensory mechanism, the common chemical sense, contributes to our senses of smell and taste. In this system, thousands of nerve endings—especially on the moist surfaces of the eyes, nose, mouth, and throat—give rise to sensations such as the sting of ammonia, the coolness of menthol, and the irritation of chili peppers. In the mouth, along with texture, temperature, and the sensations from the common chemical sense, tastes combine with odors to produce a perception of flavor. Flavor lets us know whether we are eating a pear or an apple. You recognize flavors mainly through the sense of smell. If you hold your nose while eating chocolate, for example, you will have trouble identifying it—even though you can distinguish the food’s sweetness or bitterness. That’s because the familiar flavor of chocolate is sensed largely by odor, as is the well-known flavor of coffee.

➜ Alcohol, absorbed directly from the stomach. ➜ Plant proteins tend to be less digestible than animal proteins. ➜ When food is consumed on an empty stomach, it has more contact with gastric secretions and is absorbed faster than if it were consumed on a full stomach. ➜ Certain medicines inhibit nutrient absorption, and in turn, certain foods interact with medicines, making the drugs less effective or toxic. (src)

Whole Foods

The most nutritious foods for your body are whole, minimally processed foods. Foods that fall into this category include: ➜ Fruits and vegetables ➜ Herbs and spices ➜ Meat, seafood, fish, and poultry ➜ Eggs ➜ Whole, minimally processed grains such as brown rice and buckwheat ➜ Dairy products ➜ Nuts, seeds, and legumes

If you enjoy soda and buy the standard 20-ounce bottle, you’ll be getting 65 grams of sugar, which amounts to nearly two shot glasses full of sugar.

According to the US Department of Agriculture (USDA), the American food supply provides about 3,800 calories per day per person, about 800 calories more per day than in the 1950s.

Dr. Andrew Weil notes that almost 50 percent of Americans get at least a third of their daily calories from junk food.

According to the Center for Food Safety, about 75 percent of the processed foods in supermarkets contain some genetically modified ingredients (GMO). Most of these ingredients are derived from genetically modified corn and soy.

One egg has about 140 mg of cholesterol, mostly in the yolk. Eggs are also high in protein and contain a number of nutrients, including vitamins A, B6, B12, and D, as well as magnesium and potassium.

Salmon high in fat (for a fish), but it’s also high in healthy omega-3 fatty acids also high in vitamin D and serves as an excellent source of protein.

Spinach is delicious raw, in salads, or sauteed with a little olive oil and lemon juice. Is very low in calories and contains a moderate amount of fiber. Spinach is high in vitamin A, vitamin C, iron, potassium, vitamin B6, and magnesium.

Both omega-6 and omega-3 fatty acids are essential fatty acids, and your body needs an omega-6 to omega-3 ratio of about 1:1 to 2:1.

Pregnant women need to eat foods rich in this nutrient, such as spinach, asparagus, oranges, and legumes. Pregnant women need 600 mcg of folic acid daily.

Lentils - 9gr Carbs / 9gr Protein / 2gr natural sugar (when half cup) (src)

Lactose is the primary carbohydrate in milk.

Approximately 85 percent of the water absorption by the gut occurs in the jejunum (is the second part of the small intestine).

Digestion

When you eat or drink, your body begins to break down the foods and move them through the digestive tract. In the stomach, the food mixes with stomach acid, which breaks down proteins. Next, it moves into your small intestine. There, bile acids from the liver and pancreatic juice from the pancreas mix with the foods to break down fat and further break down starches and proteins. When the breakdown of food is complete in the small intestine, small fingerlike structures on the walls of the intestine called villi absorb the nutrients from the broken-down food and feed them into the bloodstream so they can nourish your body. Finally, the remainder waste products, now relatively devoid of nutrients, mix with water in the large intestine to form stool. From there, the stool travels into the rectum and exits the body through the anus.

While the stomach supplies acid to break down foods and controls the speed of release of food particles into the small intestine, the only substance the stomach absorbs and feeds into the bloodstream is alcohol. The small intestine in an adult is about 22 feet long stretched to its full length, but it is so tightly packed together that it fits within your abdominal cavity.

The small intestine contains three separate parts:

➜ duodenum ➜ jejunum ➜ ileum

In the duodenum, the broken-down food mixes with bile and pancreatic juices, which contain enzymes to break down food and extract individual nutrients. The jejunum is lined with mucosal folds to increase its surface area in order to optimize absorption. The jejunum also contains small fingerlike projections called villi as well as tightly packed microvilli. These tiny projections absorb the nutrients, passing them through the mucosal folds and into the bloodstream to nourish the body. Finally, the remaining mixture moves into the ileum, where the body reabsorbs the bile acids to be returned to the liver. While most nutrients are absorbed in the jejunum, it is in the ileum where the body absorbs vitamin B12 into the bloodstream.

Metabolism of fuel in your body requires chemicals and hormones to convert food or body fat into energy. During the process of digestion, food mixes with digestive juices and is broken down into its energy-containing macronutrients (protein, carbohydrates, and fats). This process releases specific vitamins and minerals for absorption into the body. Macronutrients are further broken down into energy-containing units the body can absorb easily, such as amino acids, glucose (simple sugars), and fatty acids. Once absorbed into the bloodstream, these particles travel to the body’s cells, where they are metabolized as energy. If the energy supplied to the body via food (measured as kilocalories, but known simply as “calories”) is sufficient to meet the body’s energy needs, then all of the food energy is used. If food energy exceeds the body’s needs, then the body stores the surplus energy in the fat cells for later use. If food energy isn’t sufficient to meet the body’s needs, then the body pulls energy from its fat stores. This is a simplified explanation of metabolism, but the conversion of food to energy can vary significantly from person to person based on a number of factors, including hormonal levels in the body, the age and sex of the person, the amount of lean body mass, and so on.

Carrots are high in beta-carotene, which converts to vitamin A in the body. According to Scientific American, vitamin A allows the eye to convert low light signals, and it helps keep the cornea healthy.

Vitamin D, synthesized from sunlight and found in fortified dairy products, is an essential hormonal regulator within the endocrine system, so consuming adequate levels is necessary for endocrine health.

Cholesterol is an essential component in hormone creation throughout the body. Consuming moderate amounts of dietary cholesterol, found in animal proteins, can also help with hormone balancing and creation. Antioxidants such as vitamins C, E, and A can help keep hormones balanced by preventing or reversing oxidative stress.

Brain accounts for about 20 percent of the body’s total energy usage on a daily basis. A majority of this energy usage goes to the firing of neurons to send signals throughout the body.

GLUCOSE

Your brain and nervous system need glucose for fuel.

Because neurons can’t store glucose on their own, they must get them from supplies of glucose in the bloodstream. Glucose, or blood sugar, comes from consumption of simple and complex carbohydrates, as well as from the synthesis of proteins. Complex carbohydrates are the most consistent and efficient form of glucose to fuel your brain. Because they contain complex sugars and often fiber, the body absorbs them more slowly into the bloodstream, which ensures steady delivery of glucose to the brain. Simple carbohydrates raise blood sugar rapidly, causing the pancreas to release insulin quickly into the bloodstream. Insulin is a hormone that reduces blood sugar levels by moving the fuel that the blood glucose provides into storage. It also controls the release of stored fuel from the fat cells into the bloodstream for immediate use.

PROTEIN

The body uses amino acids from the protein you eat to make neurotransmitters, or other brain chemicals that enhance or inhibit brain function. Different amino acids have differing effects on the brain. For example, tryptophan has a light sedating effect on the brain, while tyrosine stimulates it. Because of the brain’s use of amino acids, you need to have protein in your diet. Good sources of protein include meat and poultry, dairy products, soy, and plant combinations that together make a complete protein, such as rice and beans.

FAT

About two-thirds of your brain volume consists of fat. Brain neurons have layers of fatty acid molecules in their cell membranes, which come from the fat in your diet. Neurons are also protected in a myelin sheath, which is mostly made up of fatty acids. Along with providing protection for neurons, your brain also requires fatty acids, particularly omega-3 and omega-6 fatty acids, to make long-chain fatty acids used in cell membranes. Fatty acids also assist in the release of neurotransmitters, as well as in cognitive function. Omega-3 and omega-6 fatty acids are often called essential fatty acids (EFAs) because, while your body needs them, it does not produce them on its own. Instead, you need to get these EFAs from dietary sources such as plant and animal foods. EFAs are so important to the brain that some medical studies link low EFA levels to diseases such as depression, Alzheimer’s, and Parkinson’s.

CHOLESTEROL

Because cholesterol is closely correlated with heart disease, many people believe that foods containing cholesterol should be completely avoided. In fact, your body needs cholesterol, which is naturally produced in the liver. Cholesterol is essential for brain function. Approximately 25 percent of the body’s cholesterol is used to help build membranes in the brain and assist in the synthesis of important substances like vitamin D, cortisol and sex hormones.

There are dietary approaches to improving HDL (good cholesterol) while decreasing LDL (bad cholesterol) :

➜ Choose foods high in soluble fiber, such as oatmeal, bran,and vegetables. ➜ Eat plenty of fish, seafood, and other foods high in omega-3 fatty acids. ➜ Enjoy extra-virgin olive oil in moderation. ➜ Cut back on saturated fats and eliminate trans fats. ➜ Include plenty of fresh fruits, vegetables, and whole grains in your diet.

FLAVONOIDS

Flavonoids have been shown to improve blood flow to the brain, which can help provide fuel and improve cognitive function. Flavonoids are polyphenol phytonutrients. They have antioxidant properties, and also help fight inflammation. You can find them in :

➜ red wine ➜ chocolate ➜ apples ➜ tomatoes ➜ bananas ➜ blueberries ➜ cherries ➜ raspberries, and many other plant foods.

VITAMINS

According to an article in the Natural Review of Neuroscience, the brain needs an array of vitamins for proper functioning. Rather than popping a pill, the best source of vitamins is a natural one: the foods you eat. Obtaining vitamins mostly from supplements doesn’t nourish your body in the same way and, in some cases, may even be toxic. Vitamins are generally classed as either water-soluble or fat-soluble. The water-soluble vitamins generally act as precursors to coenzymes (coenzyme = substance that enhances the action of an enzyme). In short :

VITAMIN A Is a group of fat-soluble compounds crucial for many functions in the body. The majority of the vitamin A in the body is stored in the liver as retinyl esters. There are two types of chemicals in this group.

PREFORMED VITAMIN A Retinoids are fat-soluble compounds (retinol, retinoic acid, and others) that are found in animal sources. The body can use these preformed types of vitamin A right away.

PROVITAMIN A Are substances that the body converts into vitamins. Carotenoids are a source of provitamin A. Of the more than 500 different carotenoids, about 10 percent are considered to be vitamin A sources, the most important of which is beta-carotene.

VITAMIN B Comprises a group of water-soluble vitamins that are essential for converting carbohydrates into usable energy and metabolizing fats and proteins. There are eight B vitamins, each of which plays a unique role in healthy body function.

VITAMIN B1 (THIAMINE) Is also known as thiamine or thiamin. It is essential for the formation of adenosine triphosphate (ATP), which the cells use for energy. It also helps strengthen the immune system.

VITAMIN B2 (RIBOFLAVIN) Riboflavin is an antioxidant vitamin that helps counteract the effects of the free radicals that form as a result of oxidative stress in the body. It also works synergistically with other B vitamins including folate and vitamin B6, converting them to usable forms. Along with vitamins B12 and B5, riboflavin helps the body produce red blood cells.

VITAMIN B3 (NIACIN) Has several different names, including nicotinic acid and niacin. It also comes in multiple forms, including niacinamide, nicotinamide, and inositol hexanicotinate. Vitamin B3 has multiple functions in the body, including hormone production and aiding circulation.

VITAMIN B5 (PANTOTHENIC ACID) Plays several roles in the body, working synergistically with other B vitamins. For example, it works with vitamin B2 and vitamin B12 in red blood cell formation, and it helps the body use the other B vitamins.

VITAMIN B6 (PYRIDOXINE) Pyridoxine is essential for the production of neurotransmitters, which are necessary for normal nerve function. It also plays an important role in brain function, helping produce hormones such as serotonin, melatonin, and norepinephrine.

VITAMIN B7 (BIOTIN) Is also known as biotin or vitamin H. This vitamin is especially essential during pregnancy because it supports growth of the embryo.

VITAMIN B9 (FOLIC ACID) Also known as folate, folic acid plays important roles in the body, including healthy brain function, fetal development, and mental health. It is also essential for the development of RNA and DNA, as well as red blood cells and tissue growth.

VITAMIN B12 (COBALAMIN) This is one of the most important B vitamins. It plays a key role in DNA and RNA development, helps form healthy blood cells, provides energy, and controls homocysteine levels in the blood.

VITAMIN E This vitamin exists in eight forms: alpha-, beta-, delta-, and gamma-tocopherol, and alpha-, beta-, delta-, and gamma-tocotrienol. The form your body uses the most is alpha-tocopherol. Research at Oregon State University in 2015 showed that low levels of vitamin E increased the risk of developing Alzheimer’s disease. You can get more vitamin E in your diet by eating avocados, almonds, and sunflower seeds.

B-COMPLEX VITAMINS Your brain needs B-complex vitamins for good health. According to an article in the December 2010 issue of the journal Nutrition Review, deficiencies in folate and vitamins B6 and B12 correlated with reduced cognitive function. All types of animal proteins are excellent sources of B-complex vitamins.

VITAMIN D Is a fat-soluble vitamin. While it is present in a few foods, most of the vitamin D the body receives is synthesized from the sun. According to the Vitamin D Council, low blood levels of vitamin D correlate with a higher risk of developing cognitive impairment. Vitamin D has protective benefits for the brain, including reducing the risk of developing brain diseases, regulating immunities, and decreasing toxins in the body. Fatty fish and cod liver oil are the best food sources of this vitamin. If you live in a low-sun climate or don’t spend much time in the sun, then supplementation may be a good choice for you. Before relying on vitamin D supplements, discuss your vitamin D status with your primary health care provider to avoid potential toxicity.

VITAMIN C Works in the brain in an antioxidant capacity. It also assists in a number of brain functions such as collagen production. Studies show it provides a protective benefit against stroke and Alzheimer’s disease. Good dietary sources of vitamin C include cantaloupe, citrus fruits, and kiwis.

VITAMIN C (ASCORBIC ACID) Is an essential water-soluble vitamin. It is an antioxidant that fights free radicals, and the body uses it for a number of important functions. *some studies show that high-dose supplementation of vitamin C may slow reproduction of cancerous cells for certain types of cancer, including prostate, pancreatic, colon, and liver cancers.

VITAMIN K Is a fat-soluble vitamin that is necessary for blood clotting. Infants are born without vitamin K, which is why hospitals routinely administer a vitamin K shot at birth.

CHOLINE Plays an essential role in normal brain function. While it can be made in the liver, you can also get it from dietary sources, such as quinoa, soy, and cruciferous vegetables. Choline is particularly important in the developing brain, so pregnant women should consume a diet rich in this nutrient. According to a 2004 study in the Journal of the American College of Nutrition, adequate choline during pregnancy can improve lifelong memory for the fetus.

BETA-CAROTENE An antioxidant that converts to vitamin A, may boost longterm cognitive development, according to the Physicians’ Health Study II. The study followed men over the short term and long term and discovered that those with long-term beta-carotene supplementation scored much better on cognition than their counterparts, who received a placebo.

MINERALS

A number of minerals may also provide protective benefits in the brain. The best way to make sure you get enough of these trace elements is to eat a variety of foods rather than relying on supplementation.

SELENIUM Deficiency can suppress or alter hormone production. Foods high in selenium include Brazil nuts, brown rice, chia seeds, and shiitake mushrooms. It is a component of about 24 selenoproteins that are crucial for protection from free radicals, reproduction, and the metabolism of thyroid hormones. These selenoproteins can be found in the blood, organs, testicles, prostate gland, and cell membranes. Selenium is absorbed easily in the gut.

CALCIUM Eating a diet with adequate calcium may provide protection against development of Alzheimer’s disease. Calcium deficiency has been linked with some forms of mental illness. Is the most plentiful mineral in the human body and is best known as a component of bones and teeth.

ZINC Is essential for brain development and neurotransmission. Low consumption of zinc during pregnancy correlates with nervous system abnormalities in the fetus, according to an article in the journal Biological Psychiatry. Foods high in zinc include shellfish, red meat, and legumes. Is an important trace mineral necessary for good health. It also works as a cofactor with a number of enzymes. Zinc naturally occurs in foods and is found in cells throughout the body.

IRON Serves as a cofactor in neurotransmitter synthesis. It also plays a key role in transporting oxygen to the brain. Foods high in iron include organ meats, shellfish, red meat, and dark leafy greens.

COPPER Plays a key role in a number of brain functions. Copper also protects against Alzheimer’s disease, Parkinson’s disease, and other illnesses. Foods high in copper include dark leafy greens, summer squash, and asparagus. is an essential trace element that is critical for many body functions. Very little copper is stored in the body, about 80 to 100 mg, or less than the amount in a penny. Copper is stored mostly in the liver, brain, and muscles.

ALUMINUM Is the most abundant metallic element on earth, making up about 12 percent of the earth’s crust. This mineral is found in every biological entity on the planet—animal, plant, and human. Aluminum is not considered highly toxic because it is not easily available. However, it is not considered nutritionally beneficial for living organisms, either. Aluminum can interfere with the absorption of calcium, iron, and magnesium because it has a similar size and electrical charge to these minerals. When someone is healthy, only about 0.3 percent of ingested aluminum is absorbed and then eliminated through the kidneys.

BISMUTH Is a heavy metal but not considered to be as toxic as lead or arsenic. It is about 86 percent as dense as lead, and some countries, such as Denmark, the United States, and England, use it as a replacement for the more toxic metal for plumbing and soldering purposes.

CHLORIDE Is a mineral that is essential for good health. It is an electrolyte as well, which means it is water-soluble and carries an electrical charge.

CHROMIUM Is considered to be a trace mineral, and more research is required to determine exactly how much is needed for optimal health. The absorption rate of chromium in the small intestine is not high, about 0.4 to 2.5 percent, and the unabsorbed mineral is excreted through feces. The liver, soft tissues, spleen, and bones contain most of the body’s stored chromium.

FLUORIDE Is a trace element that is important for dental health. There are approximately 2.6 g of fluoride present in adults, about 99 percent of which is located in the bones and teeth. When ingested, fluoride is absorbed in the stomach and small intestine into the bloodstream, where it travels to mineralized tissue such as teeth and bones.

IODINE Is a trace element that is essential to healthy thyroid function. A common dietary form of iodine is iodide, a salt that is absorbed very quickly in the stomach and small intestine. Iodide then travels to the thyroid gland, where it is used in thyroid hormone synthesis, and any excess is excreted in the urine. Most adults store 15 to 20 mg of iodine, 70 to 80 percent of which is in the thyroid gland. Iodine is a component of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). Thyroid function is controlled by thyroid stimulating hormone (TSH), which is secreted by the pituitary gland.

LEAD Is a toxic mineral. It is the most common contaminant in the human body and environment. Lead naturally occurs deep in the ground, and humans were mostly shielded from dangerous levels of this mineral until the advent of silver smelting, of which lead is a by-product.

MANGANESE Is an essential mineral and is crucial for bone growth, healthy nerves, immune system functioning, and blood sugar regulation. Manganese is found in cellular enzymes, in particular in mitochondria. When ingested, the absorption rate of manganese is between 1 and 4 percent, and manganese is then carried to the liver and other tissues to be stored. Most people store 15 to 20 mg in the bones, liver, kidneys, pituitary gland, adrenal glands, and pancreas. Manganese is excreted through feces and bile, with a little in the urine.

MOLYBDENUM Is a trace element that is necessary for the human body to function. When ingested, molybdenum is quickly absorbed in the stomach and small intestine. It travels through the blood in red blood cells and, bound to alpha-macro globulin, to the liver and other tissues.

SILICON Is the second most common element on earth. Silicon represents about 1 percent of human body weight and is found in the skin, blood vessels, cartilage, tendons, and bones. Silicon provides stability and strength, so it is essential for helping to strengthen connective tissues in the human body.

SODIUM Is an essential mineral that is crucial for life. Salt is formed when sodium combines with chloride. Sodium is an electrolyte, a positively charged cation, formed when salts dissolve in a fluid. There is more sodium outside the cells than inside, where potassium is the principal cation. Studies have shown that between 20 and 40 percent of resting energy of the body goes toward regulating sodium and potassium concentrations across the cell membranes (called membrane potential).

SULFUR Is considered to be an essential mineral and is stored in every cell in the body, especially the muscles, hair, joints, and skin. Adults store approximately 140 g of sulfur in the body, mostly in the form of amino acids such as cysteine and methionine. Dietary sources of sulfur are needed to replenish its supply in the body, because sulfur is used daily by the body for an array of functions.

TIN Tin is a trace mineral that can be found in small amounts in the body, especially in the suprarenal glands, brain, liver, thyroid gland, and spleen. Researchers are not sure exactly how necessary tin is to good health because it is not found in newborns or many animals, but some studies indicate that this mineral merits a closer look.

VANADIUM Is considered to be an essential trace element, but more research needs to be conducted on its effects. Vanadium is found in the soil, and the amount present influences how much of this element ends up in the food that grows in the soil. When ingested, 5 to 10 percent of vanadium is absorbed. Vanadium is used rapidly in the body and then excreted in the urine if not needed. Any unabsorbed vanadium is eliminated in the feces. Vanadium is stored in tiny amounts all over the body, about 20 to 25 mg in total, especially in the fat tissue.

CARBOHYDRATES

come in two forms: ➜ simple ➜ complex

Simple carbohydrates are either monosaccharides (consisting of one sugar molecule) or disaccharides (two sugar molecules). Glucose is the most plentiful monosaccharide, while sucrose and lactose are the most common disaccharides.

Complex carbohydrates contain multiple sugar molecules. They include oligosaccharides (three to ten sugar molecules linked into chains) and polysaccharides (chains of up to thousands of sugar molecules). Oligosaccharides are mostly indigestible by humans, acting as a prebiotic, meaning that they feed the ‘good’ bacteria in the gut. Polysaccharides are classified as either starch (digestible) or fiber (indigestible) and are highly beneficial to the body.

THE ROLE OF CARBOHYDRATES

The primary role of carbohydrates is to provide the body with energy. The digestive system breaks down carbohydrates, converting them to glucose. The cells in the body then burn the glucose to produce a molecule called adenosine triphosphate (ATP), which regulates the storage and release of energy from cells. Insulin, which is secreted in the pancreas, acts as an energy storage hormone. Insulin prompts the use of glucose to meet the body’s energy needs or to be stored in the form of body fat. So, if more carbohydrates are consumed than are needed, the resulting glucose will be stored as fat. Simple carbohydrates can be absorbed so quickly that insulin cannot be released efficiently enough to return blood glucose levels to a desirable level, creating spikes in blood sugar levels. Complex carbohydrates take longer to digest than simple carbohydrates, making them less likely to cause dramatic spikes in blood sugar. Any excess glucose is converted to glucagon. The body stores about 400 g (1,800 calories) of glucagon in the liver and muscles for later use, in case glucose levels drop too low. The stored energy is then released into the blood to balance blood sugar levels.

The USDA recommends that carbohydrates make up 45 to 65 percent of the daily calories for older children and adults, which is about 130 g in a 2000-calorie daily diet.

FATS

Fats (lipids) contain mixtures of fatty acids crucial for a healthy body. Fatty acids can be :

➜ saturated ➜ unsaturated

All fats are composed of chains of carbon atoms with attached hydrogen atoms. The carbon atoms of a saturated fat are attached with a single bond, whereas an unsaturated fat has carbon atoms attached with double bonds. Within unsaturated fats, there are two categories: a monounsaturated fatty acid has only one double bond, while a polyunsaturated fatty acid has more than one.

OMEGA-6 AND OMEGA-3 Two essential fatty acids are linoleic acid (omega-6 fatty acid) and alpha linoleic acid (omega-3 fatty acid). These essential fatty acids must come from food because the body cannot make them. Omega-6 fatty acids are important for cell growth, brain development, and nerve message transmission. Omega-3 fatty acids, including ALA, EPA, and DHA, are crucial for maintaining a healthy heart, ameliorating inflammatory diseases, reducing bad cholesterol, and promoting brain development.

THE ROLE OF FAT

Fat is not absorbed easily in the stomach, thereby making you feel full longer. When the fat reaches the intestine, the gallbladder releases bile, an emulsifier that allows fat to mix with water and enzymes to break it down into fatty acids and glycerol. The fatty acids are either used to make the lipoproteins that carry fats throughout the body, or are stored in fat cells to use as energy. Fats have many functions in the body:

➜ Help regulate blood sugar ➜ Transport hormones and fat-soluble vitamins, such as vitamins A, D, E, and K, throughout the body ➜ Produce hormones, such as testosterone and estrogen ➜ Insulate the body ➜ Promote a healthy brain, which is 60 percent fat ➜ Provide a source of immediate and stored energy ➜ Supply essential nutrients for cell function and repair

PROTEINS

Are composed of long chains of amino acids and are present in every cell in the body. Cells in the digestive tract, however, cannot absorb anything bigger than one or two connected amino acids, called peptides. Digestive enzymes are required to break up the long chains into individual amino acids. Once the peptides are absorbed, enzymes in the cells use the amino acids to build new proteins. This process, called protein synthesis, releases other elements used by the body. The leftover carbon, oxygen, and hydrogen from this process are converted to glucose and used for energy. The nitrogen residue (ammonia) is transported to the liver and converted to urea, which makes urine. The body uses protein quickly, requiring a consistent supply from food sources. Your body needs 22 different amino acids to create all the proteins it needs, 10 of which must come from food sources. These 10 are called essential amino acids. Your body makes the remaining 12 amino acids.

THE ROLE OF PROTEIN

The proteins in the body have unique tasks:

➜ Proteins such as keratin and collagen give strength and structure to hair, nails, skin, bones, and teeth. ➜ Enzymes are made using about half of your dietary protein. Enzymes are the catalysts for the complex reactions in the body. ➜ Antibodies are blood proteins in the immune system that neutralize and attack invaders in the body such as bacteria and viruses. ➜ The outer and inner membranes of all cells contain protein that helps move nutrients and waste to and from every part of the body. ➜ Hormones are chemicals that carry messages around the body. Insulin and glucagon are well-known protein hormones that regulate blood sugar. ➜ Minerals and proteins keep the body fluid level in balance. Proteins attract water and are too big to pass through membranes, so they maintain the correct amount of fluid in the blood. ➜ The brain needs a constant supply of glucose to function, so when no energy is available from carbohydrates and fat, the body takes protein from the muscles and other tissues. ➜ Protein is negatively charged, allowing it to pick up hydrogen atoms (positive charge) when the blood is too acidic, or release them if the blood is too alkaline. This allows the body to maintain a very precise pH. ➜ Ferritin is a protein that is the main storage form of iron in the body, holding 4500 iron molecules per protein molecule.

Animal-based proteins, such as meat, poultry, fish, seafood, dairy products, and eggs, provide all 10 essential amino acids. With the exception of soy and quinoa, plant-based proteins are incomplete. No one protein source contains all 10 essential amino acids. Plant foods, then, must be combined to create a complete protein.

WATER

Over half of the volume of your body is made up of water. It is integrated into every piece of you, and it plays a vital role in every single part and process of your body. Next to air, water is the most important substance you provide your body with. In fact, you can live for only about eight days without water.

WHERE THE WATER GOES

Different parts of your body are thirstier than others. For example, your skin is about 64 percent water, while your brain and heart are composed of about 73 percent water. Even your bones contain more than 30 percent of their volume in water.

WHAT THE WATER DOES

Water plays so many roles in your body that it is essential to life itself. In the body, water:

➜ is a building block for cells, assisting in cell reproduction and growth, and forming part of the cell’s structure. ➜ regulates your body temperature, helping to keep you within a safe and healthy range. For example, when you get too hot, you sweat. ➜ plays a vital role in digestion, helping to convert food to energy and nutrients. It is also part of saliva, which starts the process of breakdown as you chew and swallow your foods. ➜ is used to manufacture chemicals in the brain, such as neurotransmitters and hormones. ➜ transports micro- and macronutrients in the bloodstream to every cell in your body. ➜ protects your organs, nerves, and bones, and provides a cushion for your spinal cord. ➜ carries oxygen to every cell in your body. ➜ helps flush waste products that your body does not need, via sweat and urine. ➜ protects the developing fetus as a part of amniotic fluid. ➜ keeps your joints from getting creaky by forming synovial fluid, which provides lubrication and cushioning. ➜ keeps all of your mucous membranes, such as your eyes, moist and supple.

In general, a male adult needs approximately 3 liters of water each day, while an adult female needs around 2.2 liters.

WATER AND ELECTROLYTES

In your body, water mixes with other chemicals and fluids, including electrolytes. The water and electrolytes in your body coexist in a delicate balance, and the body does everything it can to maintain this balance. Electrolytes are minerals that have an electrical charge. They cause the contraction and relaxation of every muscle in your body, including your heart. When you have too much water in your system, your electrolytes may become diluted and inefficient. When you have too little water, your electrolytes may become too concentrated. To a great extent, your body maintains this delicate balance very well, holding onto water when the concentration gets a little high, and excreting water when the electrolytes are too dilute. Sometimes extreme conditions may affect this delicate balance. These may include intense exercise, extremely hot weather, drinking a lot very quickly, vomiting, and diarrhea.

*electrolytes = are minerals in the body that have an electrical charge. They control muscle relaxation and contraction, including your heartbeat. Electrolyte imbalances can have mild effects, such as muscle cramping, or severe effects, such as heart arrhythmia. In extreme circumstances, such as when you engage in intense physical exercise, when you are vomiting or having diarrhea, or when you sweat a great deal, you may lose electrolytes rapidly.

ANTIOXIDANTS

The metabolism of oxygen in the body creates free radicals, which are compounds that remove electrons from healthy molecules, causing damage and deterioration. This condition is called oxidative stress. Antioxidants are substances that fight or decrease the effects of oxidative stress in the body.

FREE RADICALS

These free radicals may provide pathways for degeneration and disease, and they are also the primary cause of aging. Free radicals can damage cells and DNA. A number of factors can increase the amount of free radicals your body produces and the oxidative stress it encounters. These include:

➜ Smoking ➜ Heavy alcohol consumption ➜ Cooking fats and oils at very high temperatures or consuming oxidized fats and oils ➜ Consuming highly processed foods ➜ Consuming processed meats ➜ Cooking meats at very high temperatures

ANTIOXIDANTS TO THE RESCUE

Free radicals can do a lot of damage in the body, but there is something that can counteract their effects: antioxidants. These substances can delay or counteract the damage caused by free radicals. Substances that work as antioxidants in your body include vitamins A, C, and E, beta-carotene, lutein, and lycopene.

AGING

Since free radicals and oxidative stress play such a large role in aging, antioxidants may help slow this process. A correlation exists between consumption of a high level of antioxidants and longevity in mammals. Studies have shown that consumption of a diet high in antioxidants helps delay or prevent the onset of age-related diseases, such as macular degeneration and dementia.

PHYTONUTRIENTS

Also known as phytochemicals, are compounds derived from plants. While research remains ongoing, many people believe that phytochemicals are responsible for preventing disease. Unlike vitamins and minerals, phytonutrients aren’t necessary for survival, but they may help you be healthier. Plant foods contain more than 25,000 different types of phytonutrients. Some are antioxidants, while others may support cell pathways, improve eyesight, or prevent disease. You have probably heard the names of many types of phytonutrients in the news and health talk shows, such as carotenoids, resveratrol, lycopene, and phytoestrogens. Scientists are currently studying the effects these important plant compounds have on the human body.

PHENOLIC ACIDS

Phytochemicals in this class include anthocyanins, flavones, flavanones, and isoflavones. Phenolic acids defend plants against disease and assist in their cell growth. It is believed that when people consume plants high in phenolic acids, these may confer the antioxidant benefits that protect against diseases such as heart disease and certain cancers. While studies are ongoing into supplementation of phenolic acids such as soy isoflavones (crystalline compound) and their role in preventing diseases, the results are mixed at best. Ongoing research is still needed. However, consumption of phenolic acids in food may be beneficial to your health. Foods that are high in phenolic acids include:

➜ Apples ➜ Artichokes ➜ Barley ➜ Berries ➜ Broccoli ➜ Buckwheat ➜ Cabbage ➜ Celery ➜ Chiles ➜ Citrus fruits ➜ Cocoa ➜ Kale ➜ Legumes ➜ Oats ➜ Onions ➜ Peaches ➜ Potatoes ➜ Rye ➜ Soy ➜ Tomatoes

FLAVONOIDS

Are antioxidant compounds in plants with color-providing pigments. In human health, flavonoids may affect cell-signaling pathways as part of a complex system of communication concerning cell activity. They also have significant antioxidant properties. Some studies have shown that flavonoids provide a protective benefit in cardiac patients. They appear to help heart disease by facilitating relaxation of the arteries, known as vasodilation, as well as inhibition of platelet aggregation, which can lead to the formations of clots.

Eating a diet rich in plant foods in an array of vivid colors can ensure you get the disease-prevention benefits of these healthful compounds without any risks that may be associated with supplementation.

EATING A DIET HIGH IN PHYTONUTRIENTS

Here are some tips for adopting a diet high in phytonutrients:

➜ Eat several servings of fruits and vegetables every day. ➜ Choose 1 cup of food in each of the colors (dark greens, vibrant reds, bright oranges and yellows, purples, and whites) each day. ➜ Eat plant foods when they are in season, at the peak of ripeness. ➜ Drink green, black, or white tea. ➜ Enjoy moderate consumption of dark chocolate and red wine. ➜ Add fresh herbs to your foods, such as parsley and thyme. ➜ Add soy to your diet. (WARNING on dose) ➜ Eat a diet that is varied.

COLORS OF THE RAINBOW

Bright colors indicate high levels of phytonutrients.

Green Green fruits and vegetables contribute phytonutrients such as isoflavones, flavonoids, and lutein. Consider adding the following greens to your meals each day: ➜ Beet greens ➜ Broccoli ➜ Brussels sprouts ➜ Cabbage ➜ Collard greens ➜ Kale ➜ Mustard greens ➜ Peas ➜ Romaine lettuce ➜ Spinach ➜ Swiss chard

Red Red fruits and veggies add phytochemicals like lycopene and hydroxybenzoic acid. Adding red to your diet is easy: ➜ Cherries ➜ Pomegranate ➜ Raspberries ➜ Red cabbage ➜ Red chiles ➜ Red grapes ➜ Strawberries ➜ Tomatoes

Yellow/Orange Yellow and orange fruits, vegetables, and spices are high in beta-carotene, phthalides, and flavonols: ➜ Carrots ➜ Citrus fruits ➜ Ginger ➜ Mangos ➜ Nectarines ➜ Peaches ➜ Pineapple ➜ Pumpkin ➜ Sweet potatoes ➜ Turmeric ➜ Winter squash

White White fruits and vegetables contribute flavonols, quercetin, and allicin: ➜ Apples ➜ Coconut ➜ Garlic ➜ Onions ➜ Turnips

Blue/Purple these deeply colored fruits and veggies contain anthocyanins and resveratrol, among others: ➜ Beets ➜ Blackberries ➜ Blueberries ➜ Cocoa ➜ Eggplant ➜ Figs ➜ Purple grapes ➜ Purple potatoes ➜ Red wine

MEAT NUTRITION

Nutritionally, meat and poultry consist of protein and fat, and also contain vitamins and minerals. Meat and poultry offer an excellent source of complete protein. They are also a strong source of essential vitamins and minerals, including :

➜ iron ➜ vitamins B6 and B12, niacin, thiamin, riboflavin, vitamin E, magnesium, and zinc.

The fat in meat is mostly saturated fat. However, it does contain moderate amounts of polyunsaturated fatty acids (PUFAs) as well, which may provide protective benefits against heart disease. Organ meats (offal), such as liver, kidneys, and heart. Are especially high in iron, vitamin A, vitamins B2 and B12, zinc, and folate.

SEAFOOD

Fish and shellfish are a delicious and healthy part of a balanced diet. Foods in this category include freshwater fish, such as trout and catfish; ocean fish, such as halibut and salmon; and shellfish, such as shrimp, clams, and oysters.

SEAFOOD NUTRITION

Seafood is an excellent source of lean protein. While fish and shellfish do contain fat, the content tends to be low and mostly unsaturated. Because of this low level of fat, fish tends to be lower in calories than other types of animal proteins. Fish also contains a number of vital micronutrients.

➜ Protein: Protein in fish and shellfish ranges from 16 to 26 grams per 3-ounce serving. Because of the ratio of high protein to low fat, many people who are trying to cut back on calories and fat may prefer fish as their primary animal protein. ➜ Fat: A 3-ounce serving of fish and seafood contains 0.5 to 10 grams of fat per serving. That’s an extremely low-fat form of animal protein. Fish and shellfish that have the most fat include salmon, trout, mackerel, catfish, and oysters. While a small amount of the fat in some types of fish and shellfish (such as trout, oysters, salmon, perch, catfish, and tilapia) is saturated, fish is also an excellent source of PUFAs as well as beneficial omega-3 fatty acids. In fact, fish is the best dietary source of these essential omega-3 fatty acids. Fish highest in EFAs include wild-caught salmon, anchovies, mackerel, sablefish, whitefish, sardines, tuna, herring, and trout. ➜ Micronutrients: Seafood contains a number of essential vitamins and minerals, including B-complex vitamins, vitamin A, vitamin D, iodine, selenium, iron, and zinc.

FRUITS

Are foods that come from trees and contain seeds. There are a number of different types of fruits that confer various health benefits.

CITRUS FRUITS Are juicy, flavorful fruits with a thick peel. They include oranges, grapefruit, lemons, limes, and tangerines. They are high in flavonoids, as well as antioxidants such as vitamin C, folate, and B-complex vitamins. Citrus fruits have moderate levels of fructose, and they contain some fiber. Eating the whole fruit helps you limit the sugar consumption, while juicing increases the proportion of sugar and calories in each serving.

TREE FRUITS Like apples, pears, and figs, are fall-harvested fruits with an edible outer peel. Apples have moderate calories and fiber. They also contain a moderate amount of fructose, which is a simple sugar. They contain vitamin A and vitamin B6. Pears have a similar nutritional profile to apples, although they tend to be slightly sweeter and thus slightly higher in sugar. Figs are high in fiber and fructose. They contain vitamin B6.

STONE FRUITS Are those that contain a pit in the middle. They include peaches, plums, nectarines, cherries, and apricots. Stone fruits contain moderate levels of calories, fructose, and fiber. They are high in vitamins A and C, as well as phytonutrients and antioxidants.

BERRIES Are high in fiber and have relatively low levels of fructose. They are also low in calories. Because of their deep coloring, berries are high in antioxidants and phytochemicals.

MELONS Have a high water and fiber content, combined with a low fructose concentration. They tend to be relatively low in calories. They are also high in potassium and vitamins A, C, and B6 and contain a small amount of iron.

TROPICAL FRUITS Fruits include bananas, papayas, passion fruit, guavas, pineapples, and mangos. These fruits tend to be high in fructose and therefore more calorically dense than other fruits. These juicy fruits are high in potassium, vitamin C, phytonutrients, and enzymes.

DRIED FRUITS Such as apples, raisins, and dates, contain a concentration of nutrients. Because the water has been evaporated, they also tend to be quite high in fructose and calories per volume. After drying, they still retain the micronutrient properties of their fresh counterparts.

GRAPES Are high in water and vitamin K. They contain moderate amounts of fructose and fiber, and they are relatively low-calorie. Dark-skinned grapes contain high levels of flavonols, carotenoids, and phenolic acids, which are antioxidants.

HEALTH BENEFITS OF COFFEE

Fortunately, if you’re one of the millions of Americans addicted to your daily cup of joe, it could be conferring some health benefits as well:

➜ Some studies, including an 11-year study published in 2006 in the Archives of Internal Medicine, showed that coffee consumption seemed to provide protective benefits against the development of type 2 diabetes. ➜ Multiple studies have shown that coffee may have protective benefits against liver disease, and regular consumption may provide relief of certain symptoms associated with liver disease. ➜ Coffee is high in antioxidants, which can protect the body against and remove signs of oxidative stress caused by free radicals. ➜ A 2012 study showed that coffee consumption may help patients with Parkinson’s disease achieve better motor control. ➜ By itself, coffee is low in calories.

PROTEINS	FATS	CARBOHYDRATES
Beans (canned or dry)	Oils	Whole grains and grain products
Lentils (canned or dry)	Avocado and guacamole	Root vegetables
Dried peas	Nuts and nut butters	Winter Squashes
Tofu and Tempeh	Seeds and seed butters	Quinoa
Seitan	Coconut milk	Potatoes
Vegan meats	Dressings, sauces, and vinaigrettes	Beans (canned and dry)
Hemp seeds		Lentils (canned or dry)
Quinoa		Dried Peas

All whole-plant foods include protein and contain all 20 amino acids. For example, bananas contain 5 percent of their total calories from protein, white potatoes have 8 percent, and brown rice has 9 percent.

Furthermore, some plant foods are very high in protein, including beans, legumes, nuts, and seeds. Lentils have 36 percent, and believe it or not, leafy green vegetables have almost half their total calories from protein!

People assume that protein comes only from animal products and that anyone avoiding them will be deficient. That’s a myth! All essential amino acids originate from plants. Either you eat the plant or you eat the animal that ate the plant.

Protein combining is another myth. This idea to combine foods to get sufficient protein was popularized in the 1950s, but has since been repudiated. Ultimately, the human body is much more elegant than we give it credit. It’s able to pool together all the amino acids it absorbs from food and re-create the proteins it requires as necessary.

Food	% Calories from Protein	Protein (per serving)
Banana, 1 medium	4.6	1.2g
Brown rice, 1 cup cooked	8.5	4.9g
Barley, pearled, 1 cup cooked	9.4	16.4g
Quinoa, 1⁄2 cup cooked	14	11.1g
Whole-wheat bread, 1 slice	15.7	2.4g
Chickpeas, 1 cup cooked	21.6	14.5g
Lentils, 1 cup cooked	31	17.9g
Soy milk, 1 cup	33.4	6.6g
Broccoli, raw, 1⁄2 cup	43.3	1.3g
Tofu, raw, firm, 1⁄2 cup	43.5	19.9g
Spinach, frozen, 1⁄2 cup	44.4	3.0g