Glossary of Nutritional Terms
Compiled by Ron Avidan

The most complete glossary of bodybuilding, fitness, and supplement related nutritional terms and definitions. This is by no means a complete list, and is a work in progress. This information is for educational purposes only, and is not intended to replace any health care professionals. It is a compilation of many sources, mixed in with our opinions.

  • A (Retinol)
    Vitamin A is a vitamin with antioxidant properties, important for eye protection and bone growth; protein and hormone synthesis (including GH and testosterone); supports tissue maintenance. Helps reduce susceptibility to infection. Essential for healthy skin, good blood, strong bones and teeth, kidneys, bladder, lungs and membranes.

  • Acesulfame-K
    An artificial sweetener. Approved in 1988, this sweetener is 200 times sweeter than sugar, yet has a bitter taste. The 'K' in its name stands or potassium. Acesulfame-K is not metabolized by the body. You can cook and bake with it. There are no reported side effects with this sweetener although it may increase insulun secretion, which can cause concern for diabetics.

  • Acetyl-L-Carnitine (ALC)
    The acetyl ester of carnitine, ALC acts as an antioxidant, has protective effects in the brain, and stimulates hormone (including testosterone) release.

  • Alanine
    An amino acid. BCAAs are used as a source of energy for muscle cells. During prolonged exercise, BCAAs are released from skeletal muscles and their carbon backbones are used as fuel, while their nitrogen portion is used to form another amino acid, Alanine. Alanine is then converted to Glucose by the liver. This form of energy production is called the Alanine-Glucose cycle, and it plays a major role in maintaining the body's blood sugar balance.

  • Alpha Lipoic Acid (ALA)
    A sulfur bearing phytonutrient with antioxidant properties; amplifies effects of other antioxidants. It is an insulin potentiator that may be, in some respects, the very best insulin mimicker. An analogy of what ALA does is that if ALA was an individual, he would be the one which yells at the muscle cells to pick up the key, open the door, and help bring in the creatine.

    ALA is a sulfur bearing compound with antioxidant properties. It plays a role in energy metabolism. ALA amplifies the ability of other antioxidants to combat free redicals and enhance recovery. Also may enhance insulin sensitivity, improving the body's ability to add lean mass and reduce fat.

  • Amino Acids
    Nitrogen-bearing organic acids that are the building blocks of protein. The branched chain amino acids are Leucine, Valine and Isoleucine.

  • Anabolic
    Metabolic condition in which new molecules are synthesized (growth).

  • Androstenedione
    An androgen (male hormone). Androgens are produced in two sites in the male body - most originate in the testes, but some potent male hormones are produced by the adrenal glands, located just above the kidneys. Androstenedione is a pivotal adrenal steroid that's actually one step closer to being converted to testosterone than DHEA. It raises your testosterone levels and can provide more strength.

    Androstenedione really does raise testosterone above normal levels and could be hazardous. Side effects include acne, male baldness, and a decrease in 'good' cholesterol, which may lead to heart disease. This supplement might be reclassified as a steroid by the FDA, and it is banned in the NFL, Olympics, and other major sports organizations.

  • Antioxidants
    Any substances that prevent or impede cell oxidation (destruction) by free radicals, etc.

  • Arginine
    A conditionally essential amino acid with anabolic and immune system supportive effects. It is required for growth, immune function, wound healing and many aspects of protein metabolism. Arginine is necessary for the production of growth hormone. It is also a precursor for nitric oxide, a critical substance that helps regulate the function of cardiovascular, nervous and immune systems and which is essential for muscle growth.Arginine is essential for sperm formation, so it plays a vital role in male fertility.

  • Ascorbic Acid
    Also known as Vitamin C. A water soluble vitamin, and an antioxidant. Your body cannot store Vitamin C, so you must supplement it regularly. It is not resistant to heat, so cooking will destroy it. Vitamin C functions primarily in the formation of collagen, the chief protein substance of your body's framework. It also helps in the production of vital body chemicals. Vitamin C also is a detoxifier (helping cleanse your body of toxins).

  • Aspartame
    An artificial sweetener. Known by the trade name NutraSweet, it is an artificial sweetener. Certain people should avoid products that contain Aspartame. They are people who cannot metabolize the amino acid Phenylalanine, which is an ingredient in aspartame; and people who are suspectable to headaches.

    It is nearly 200 times sweeter than sugar. Aspartame is produced from the amino acids L-asartic acid and L=phenylalannine. It has been approved for use in certain goods since 1981. Heat causes aspartame to lose its sweetness, therefore, you can't bake with it. Unlike some sweetners, it has no aftertaste.

  • Aspirin
    Can reduce soreness after a hard workout, or lower your risk of heart disease. Can also reduce your risk for throat or stomach cancer.

  • ATP (Adenosine Triphosphate)
    The body's energy currency, released when fuel molecules are broken down.

  • B-Complex Vitamins
    A group of eleven known vitamins that work together in your body. All play vital roles in the conversion of food into energy. Essential for the normal functioning of the nervous system, and the maintenance of good digestion. Helps promote healthy skin, hair, and eyes. These are water soluble vitamins, which means they cannot be stored by your body and must be replaced every day.

  • B-1 (Thiamin)
    A vitamin which maintains energy levels, supports brain function (memory). Aids in digestion. Necessary for metabolism of sugar and starch to provide energy. Maintains a healthy nervous system. Alcohol can cause deficiencies of this vitamin and all the B-complex vitamins.

  • B-2 (Riboflavin)
    A vitamin which helps with energy production and amino acid production. Helps body obtain energy from protein, carbohydrates, and fats. Helps maintain good vision and healthy skin.

  • B-3 (Niacin)
    A vitamin Important in carbohydrate metabolism, formation of testosterone and other hormones, formation of red blood cells and maintaining the integrity of all cells. Helps body utilize protein, fats, and carbohydrates. Necessary for a healthy nervous system and digestive system. It also lowers elevated blood cholesterol levels when taken in large amounts of more than 1,000 milligrams a day.

  • B-5 (Pantothenic Acid)
    A vitamin which supports carbohydrate, protein and fat metabolism; hemoglobin synthesis. Helps release energy from protein, carbohydrates, and fat. Needed to support a variety of body functions, including the maintenance of a healthy digestive system.

  • B-6 (Pyridoxine)
    A vitamin which supports glycogen and nitrogen metabolism; production and transport of amino acids; production and maintenance of red blood cells (hemoglobin) Essential for the body's utilization of protein. Needed for the production of red blood cells, nerve tissues, and antibodies. Women taking oral contraceptives have lower levels of B-6.

  • B-12 (Cobalamin)
    Necessary for carbohydrate, protein and fat metabolism. Important to amino acid and fatty acid synthesis; essential for hemoglobin and nerve cell growth and maintenance. The anti-stress vitamin, sometimes prescribed for stress reduction.

  • BCAA's (Branch Chain Amino Acids)
    Leucine, Valine, and Isoleucine are called "branch chain" aminos due to their molecular structure, and are important essential amino acids well known for their anticatabolic (muscle-saving) benefits. They are called BCAA's because they structurally branch off another chain of atoms instead of forming a line. Studies have shown that BCAA's postively affect skeletal muscle growth, enhance fat loss, help to stimulate protein synthesis and inhibit its breakdown, so BCAA's have powerful anabolic and anticatabolic effects on the body. They may also potentiate the release of some anabolic hormones, such as growth hormone. Regular ingestion of BCAA's help to keep the body in a state of postive nitrogen balance. In this state, your body much more readily builds muscle and burns fat. Studies have shown that athletes taking extra BCAA's have shown a loss of more bodyfat than those not taking BCAA's.

    BCAAs are used as a source of energy for muscle cells. During prolonged exercise, BCAAs are released from skeletal muscles and their carbon backbones are used as fuel, while their nitrogen portion is used to form another amino acid, Alanine. Alanine is then converted to Glucose by the liver. This form of energy production is called the Alanine-Glucose cycle, and it plays a major role in maintaining the body's blood sugar balance.

  • Beta-carotene
    A phytonutrient carotenoid with antioxidant and provitamin A activity. In addition to providing the body with a safe source of Vitamin A, beta carotene works with other natural protectors to defend your cells from harmful free radical damage. This is an important micrinutrient in helping the body with metabolic functions, such as recovery from exercise. Beta-Carotene is the plant derived form of Vitamin A, which is important for several bodily functiosn, including eyesight, immune function and even bone growth. Beta-Carotene is nontoxic. Good sources of Beta Carotene include Carrots, Sweet Potatoes, Pumpkins, Cantaloupes, Acricots, Spinach and Broccoli.

  • Beta-Hydroxy Beta-Methylbutyrate (HMB)
    It is a compound mande in the body and a metabolite of the essential amino acid Leucine. Studies have found that HMB has a decrease in stress-induced muscle protein breakdown. Studies also found that HMB may enhance increases in both muscle size and strength when combined with resistance training.

    There are a number of theories why you may need HMB. The first, is that under stressful conditions, the body may not make enough HMB to satisfy the increased needs of tissues. It could also be that stress may alter enzymes or concentration of certain biochemicals that decrease normal HMB production. Another theory is that HMB may regulated enzymes sresponsible for muscle tissue breakdown.

  • Biological Value (BV)
    An attempt to measure how efficiently protein us used in the body. Biological Value is derived from providing a measure intake of protein, then noting the nitrogen uptake versus nitrogen excretion. The actually process is much more complicated though. In theory, a BV value of 100 is maximal. Some studies claim they have a higher BV than 100, but they refer to a chemical score, not the biological value of whey.

  • Biotin
    A vitamin that helps with energy metabolism, fatty acid and nucleic acid synthesis.

  • Boron
    It is a trace mineral. Studies show that Boron helps the body retain minerals, such as Calcium and Magnesium. Large amounts of Boron, over 10 milligrams a day, can be toxic, particularly to the organs that manufacture testosterone. You can find traces of Boron in all the food groups, even in wine, with the greatest concentration in prunes, raisins, parsley flakes, and almonds. A 1987 study showed that Boron could dramatically increase testosterone levels, however, the study was for postmenopausal women who had testosterone deficiencies. Once their boron-rich diets brought their testosterone levels back up to normal, those levels stabilized, and they didn't get any higher no matter how many more prunes or parsley flakes that they ate. Thus, it is somewhat unproven that boron can help build muscle mass by increasing your testosterone levels. However, a lack of boron in your diet may have a 'negative' impact on energy utilization.

  • Bovine cartilage
    A source of mucopolysaccharides which have anti-inflamatory and joint protective properties.

  • Bovine Colostrum
    Usually from cows, a dairy product that has similar properties to human colostrum. Normally, adults cannot absorb colotrum's antobodies and growth factors the way a newborn can. But it still has superior nutritional values which may make it a useful supplement.

  • Brown Adipose Tissue (BAT)
    A type of specialized fat that is known to convert fat calories into heat, thereby disspating excess calories.

  • Buckwheat
    A plan native to Asia that has fragrant white flowers and small triangular seeds. The edible seeds are often ground into flour. According to animal studies, buckwheat is better than casein (a milk protein) for promoting muscle growth and body growth and decreasing blood lipds. For persons allergic to wheat gluten, it provides a gluten-free food with uses similar to gains. Roasted buckwheat is known as Kasha. Buckwheat is usually available as flour.

  • Caffeine
    Alkaloid that stimulates alertness and boosts energy. A herbal compound that enhances alertness and fights fatigue. Caffeine increases endurance during prolonged submaximal activity by increasing blood epinephrine (adrenaline) levels, thereby allowing fat cells to break down more readily during aerobic activity. Caffeine also makes a muscle contraction more forceful.

  • Calcium
    Most abundant mineral in the body; essential for the formation and repair of bone and teeth, but also essential to nerve transmission, muscle contraction, blood clotting and other metabolic activities as well. Long term calcium deficiency is linked to degenerative bone diseases.

  • Carbohydrate
    There are two basic forms of carbohydrates: Simple & Complex. Simple carbs are usually devoid of fiber and include such foods as refined sugars, fruit juices, and apple sauce. The problem with simple carbs is that they promote a large insulin surge, which can lead to hypoglycemia. Complex carbs are absorbed more slowly, so they don't cause as great an insulin surge as the simple type. Primary macronutrient source of energy in the body; burned as glucose and stored in muscle as glycogen (excess stored as fat) and includes all sugars (1 gram yields 4 calories).

  • Carnitine (L-Carnitine)
    Non-structural amino acid that transports fatty acids into muscle cells for use as energy fuel. Carnitine is water-soluble and can be made in the body from the amino acids lysine and methionine with the assistance of vitamins C, B6 and Niacin, which act as coenzymes in the process.

    Carnitine as discovered in meat in 1905, and was once called Vitamin T, because they thought it was a vitamin at first. 98% of te body's carntine exists in the heart and skelatal muscles. Carnitine is synthesized in the liver from Lysiine and Methionine, but half of the body's daily requirement for Carnitine comes from foods sources, including meat, poultry, fish and some diary products. Without supplemental carnitine, some people cannot use fat as energy.

  • Casein
    Primary protein found in milk, along with whey protein. Casein is the insoluble protein fraction of milk. It is absorbed more slowly than whey and provides the body with amino acids over an extended period in comparison to whey protein, the soluble protein fraction in milk.

  • Catabolic
    Metabolic condition in which muscle is broken down and energy is released.

  • Catabolism
    Protein breakdown in muscles.

  • Cat's Claw
    An herb used in South American folk medicine for its anti-inflamatory and immune system protective properties.

  • Chick Embroyo Extract
    This type of extract contains short amino acid chains called oligopeptides, plus additional essential amino acids and trace elements (iron, copper, cobalt, selenium, and zinc). The peptides in the extract possess both cell stimulating and protective properties. The peptides indicated that they were activating growth factor receptors in them. The extract works as a general tonic and stimulates the adrenal gland, normalizing its function. It also acts as a mild stimulant and an antidepressant; and it improves libido, erectile function, sparmatogenesis and other aspects of sexual function in men and women. It also improves sleep and promotes weight loss.

  • Chitosan
    Chitosan is a natural product extracted from Chitin (by products of Crustacean shell extracts). Chitosan and chitin are waste products of the crab and shrimp industry. It can be used to inhibit fat digestion and as a drug delivery transport agent. It also has been used as a cholesterol lowering substance. Chitosan is marketed as a 'fat blocker'. It appears that it can impede fat absorption by 'gelling' with fat in the small intestine. Side effect of Chitosan is that since it is made from sea food, some people have allergic responses to it. Also, you need a high concentration of Chitosan for it to 'gel' with fat.

  • Choline
    A B-fatty acid involved in the production of neurotransmitters in the brain that regulate mood, appetite, behavior, memory, etc. Most effective in phosphatidyl choline form. It is beleived to help concentration and alertness. Studies indicate that it improves cognitive performance. Blood levels of choline decrease during prolonged exercise.

  • Cholesterol
    A fat-like sterol used by the body for production of hormones (including testosterone), vitamin D and cell membranes; high levels in the blood stream are a marker for heart disease.

  • Choline
    One of the elements that is found in lecithin. Considered important in the transmission of nerve impulses. Choline is involved in the formation of the neurotransmitter acetycholine. Choline has been linked to reducing bodyfat and improving exercise performance.

  • Chondroitin
    Chondroitin is extracted from bovine tracheas or shark cartilage. It is a major component of connective tissue, especially cartilage. Chondroitin can stimulate repair of cartilage cells and also black enzymes that damage joints.

  • Chromium / Chrimium Picolinate
    Chromium increases the efficiency of the hormone insulin, which the pancreas releases after you eat carbohydrates or protein. Chromium acts to make the receptor of muscle cells more sensitive to insulin (which allows you to store more carbohydrates in the muscle cells as glycogen rather than in fat cells as lipids). Insulin also helps muscles use amino acids for building protein rather than breaking them down. Chromium can promote modest muscular gains and decreases in bodyfat (thus helps build lean mass). Exercise increases the excretion rate of chromium.

  • Chrysin
    An anti-aromatase, which means it stops a lot of excess testosterone from converting to estrogen. Also, a compound with significant antiviral activity - especially in relation to the HIV. A an effect on the benzodiazapene receptors (which have a calming, antistress effect). It is possible that Chrysin taken in the correct dosage could reduce cortisol secretion due to the body's sensing less stress. Chrysin may act as an antiestrogen by inhibiting aromatase activity, limiting the conversion of testosterone to estrogen.

  • Citrimax
    See Hydroxycitrate

  • Clenbuterol
    This drug is classified as a Beta-2 agonist, and is used for treating asthma. It is not an anabolic steroid, or a growth hormone. Currently, it is not approved for sale in the United States, but it is sold in Europe, under various names, such as Spiropent, Monores, and Ventipulmin. Researchers in 1987 noted an unusual effect in animals when using this drug. Their muscles grew, while they lost body fat. The main side effects associated with this drug include tremors, heart rhythm disturbances, headaches, nervousness, excessive sweating and insomnia. Bodybuilders use it because it mimics the actions of Epinephrine. It simulates a process called Thermogenesis, which turns fat calories into heat and which results in a loss of body fat. The side effects start when you use more than 80 micrograms or more. The dosage that's used to treat asthma is around 20 to 40 micrograms twice a day. The muscle building dose would be over 80 micrograms in humans, but scientists consider it to be dangerous and unethical. Another problem is that any effects you get from it wears off rapidly. Bodybuilders who have used this drug shows that it is better for promoting fat burning than for muscle building.

  • Coenzyme Q10
    This antioxidant is shown to have heart protective and energy productive properties. COQ10 is involved in cellular energy production. Several studies have reported improved endurance after taking CoQ10. It is considered one of the best antioxidants. It may be an ergogenic aid because it plays a pivital role in a cellular process that leads to ATP synthesis and is known as the electron transport system.

  • Colostrum
    Colostrum is a fluid produced by the mammary glands of female mammals prior to milk production. It has a high concentration of immunoglobins, antimicrobial agents and hormone factors. Colostrum provides major immune and gastrointestinal system benefits.

    Bovine Colostrum usually comes from cows, a dairy product that has similar properties to human colostrum. Normally, adults cannot absorb colotrum's antobodies and growth factors the way a newborn can. But it still has superior nutritional values which may make it a useful supplement.

  • Conjugated Linoleic Acid (CLA)
    CLA occurs naturally in whole milk and red meat. A collective term used to designate a mixture of positional and geometric isomers of the essential fat linoleic acid. It is actually a fat, derived from linoleic acid (an essential fatty acid). Studies have shown that CLA can increase lean body mass and decrease fat, inhibit the growth of tumors and enhance immune function. CLA is found naturally in beef, cheese and whole milk.

  • Copper
    Active in the storage and release of iron to form hemoglobin for red blood cells.

  • Cortisol
    A catabolic hormone that is released and increases in response to stress when the body is subjected to trauma such as intense exercises, including weight training. Excess cortisol is known to increase catabolism (protein breakdown in muscles). Cortisol leads to muscle breakdown through promoting a release of muscle amino acids for transport to the liver, where the amino acids are coverted into glucose.

  • Creatine (monohydrate)
    A muscle fuel that is extracted naturally from meat and fish, or synthesized in the lab. Once it is in the muscles, creatine combines with phosphorous to make Creatine Phosphate (CP), a high powered chemical that rebuilds the muscles ultimate energy source, Adenosine Triphosphate (ATP). CP powers your muscles for high intensity exercise for short periods only, consequently, athletes who compete in power and sprint event will have an advantage if they take supplemental creatine. More CP in the muscle cell translates into a greater resistance to fatigue. Also, CP helps with the transfer of energy in the muscle cells, thus speeding up the action, which may enhance performances that are aerobically taxing. Reports says people who take creatine supplements may recover from intense activity faster and experience less postexercise muscle soreness.

    Creatine is a naturally occurring compound in the muscle tissue and when converted in the muscle tissue to phosphocreatine during exercise can provide sudden bursts of energy. Insufficient amounts of phosphocreatine could result in a fatigued feeling in the muscle. The Creatine Monohydrate Powder provides enough energy to delay to onset of fatigue. Creatine Monohydrate is a synthesized metabolite that is the powerful energizer providing instant energy and strength with better endurance and helps to maintain optimal levels of ATP production during intense exercise.

    Why Monohydrate? Creatine comes in several forms. Creatine Monohydrate, Creatine Phosphate, and liquid form. Creatine Phosphate is much more expensive to manufacture while it offers no advantage. Liquid creatine has many problems associated with it. When mixing creatine monohydrate with a protein drink, or water, the creatine starts to become unstable. Within 24 hours, the creatine begins to change or ‘fallout’ into creatinine. Creatinine is a useless substance to the body. Thus, buying a premixed liquid form of creatine is not a legitimate product. The best absorbed form of creatine is the creatine monohydrate. Creatine monohydrate is better absorbed because it is more stable, resulting in higher concentration of available creatine.

    Creatine & ATP. ATP is the molecule that releases the energy for contraction of muscles, the breakdown and synthesis of proteins and all other reactions requiring energy. In short, ATP is the energy molecule powering all of our movements. By giving off its energy through its high energy phosphate bond, ATP is reduced to ADP. The problem is that the amount of ATP that is stored in our cells is limited. Depending on the intensity of the activity, ATP supplies can be used up by converting to ADP within seconds. So how do athletes run or workout for long periods. We can do that because there are three way to replenish ATP.

    1) You can restore ATP using energy derived from the oxidation of fats and carbohydrates. This is a slow process that occurs in the mitochondria. 2) You can restore ATP through lactic acid, which is utilized to produce energy, which turns ADP back into ATP. 3) Through Creatine Monohydrate, which helps creatine phosphate create more ATP from ADP within seconds. It is a short term, high energy backup for ATP. It does not need carbohydrates, fats or oxygen to recharge ATP.

  • Creatine (titrate)
    Titrated creatine is less expensive than effervescent creatine, but has the same total solubality and absorbability. The result is free-ionized, soluble creatine. Titrated creatine acheives the process by titrating, or changing, the pH of the water when it's stirred in. The altered pH solution enables more than 95 percents of the creatine to go into solution, so you get dissolved creatine.

  • Diuretic
    Any agent or compound that increases the flow of urine from the body. They can range from herbal teas to powerful drugs that flush out electrolytes and water. They are classed based on the location and mechanism of action in the kidneys. Athletes use diuretics to eliminate water weight to further emphasize their muscular definitions. Most bodybuilding and fitness federations have banned the use of diurectics and test for them.

  • DHEA (Dehydroepiandrosterone)
    A hormone made by the adrenal glands used by the body to make male (androgen) and female (estrogen) hormones; possible positive effects on mood and energy on older individuals (40+) whose production of DHEA has declined. As been referred to as the 'Fountain of Youth' hotmone bacause it declines rapidly as we age, and supplementation with this hormone reverses many of the ravages associated with aging. Studies show that men with the highest DHEA levels have better cardiovascular health.

  • DMAE (Dimethyl-amino-ethanol)
    Supplement reported to minimize buildup of lipofuscin (age spots) in the brain. Plays a participatory role in acetycholine synthesis. DMAE has been shown to stimulate vivid, lucid dreams, suggesting possible sleep pattern enhancement.

  • DNP (2,4 dinitrophenol)
    The first weight loss drug ever offered to the public, around 1933. DNP is a yellow crystalline sold that's slightly soluabl;e in water. After being injected, it increases the metabolism an average of 30% over baseline in less than a minute, returning back to normal anywhere from 6 to 48 hours. However, DNP has way too many side effects, including blinding people, and if you take too much of it, it can cook you to death from the inside. You can lose weight with it, but it is highly dangerous. Street Names for DNP include Hexalon. DNP is now classified as a poison.

  • DOMS (Delayed-onset muscle soreness)
    The pain and soreness you feel a few days after a heavy workout.