This is an accepted version of this page
79-442: Creatine ( / ˈ k r iː ə t iː n / or / ˈ k r iː ə t ɪ n / ) is an organic compound with the nominal formula (H 2 N)(HN)CN(CH 3 )CH 2 CO 2 H . It exists in various tautomers in solutions (among which are neutral form and various zwitterionic forms). Creatine is found in vertebrates , where it facilitates recycling of adenosine triphosphate (ATP), primarily in muscle and brain tissue. Recycling
158-446: A clinical study focusing on people with various muscular dystrophies, using a pure form of creatine monohydrate can be beneficial in rehabilitation after injuries and immobilization. Creatine's impact on mitochondrial function has led to research on its efficacy and safety for slowing Parkinson's disease . As of 2014, the evidence did not provide a reliable foundation for treatment decisions, due to risk of bias, small sample sizes, and
237-510: A deficiency state that compromises growth, survival and reproduction. Consumer advisories for dietary nutrient intakes such as the United States Dietary Reference Intake , are based on the amount required to prevent deficiency and provide macronutrient and micronutrient guides for both lower and upper limits of intake. In many countries, regulations require that food product labels display information about
316-593: A dietary inadequacy". In setting human nutrient guidelines, government organizations do not necessarily agree on amounts needed to avoid deficiency or maximum amounts to avoid the risk of toxicity. For example, for vitamin C , recommended intakes range from 40 mg/day in India to 155 mg/day for the European Union. The table below shows U.S. Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for vitamins and minerals, PRIs for
395-597: A dozen minerals absorbed through roots, plus carbon dioxide and oxygen absorbed or released through leaves. All organisms obtain all their nutrients from the surrounding environment. Plants absorb carbon, hydrogen, and oxygen from air and soil as carbon dioxide and water. Other nutrients are absorbed from soil (exceptions include some parasitic or carnivorous plants). Counting these, there are 17 important nutrients for plants: these are macronutrients; nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sulfur (S), magnesium (Mg), carbon (C), oxygen(O) and hydrogen (H), and
474-441: A high dicyandiamide concentration. Heavy metals contamination was not found to be a concern, with only minor levels of mercury being detectable. Two studies reviewed in 2007 found no impurities. When creatine is mixed with protein and sugar at high temperatures (above 148 °C), the resulting reaction produces carcinogenic heterocyclic amines (HCAs). Such a reaction happens when grilling or pan-frying meat. Creatine content (as
553-412: A lower dose of 3 grams a day for 28 days can also increase total muscle creatine storage to the same amount as the rapid loading dose of 20 g/day for 6 days. However, a 28-day loading phase does not allow for ergogenic benefits of creatine supplementation to be realized until fully saturated muscle storage. This elevation in muscle creatine storage has been correlated with ergogenic benefits discussed in
632-624: A nutrient does harm to an organism. In the United States and Canada, recommended dietary intake levels of essential nutrients are based on the minimum level that "will maintain a defined level of nutriture in an individual", a definition somewhat different from that used by the World Health Organization and Food and Agriculture Organization of a "basal requirement to indicate the level of intake needed to prevent pathologically relevant and clinically detectable signs of
711-1161: A percentage of crude protein) can be used as an indicator of meat quality. Creatine-monohydrate is suitable for vegetarians and vegans, as the raw materials used for the production of the supplement have no animal origin. Organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond ; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane CH 4 ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic , such as halides of carbon without carbon-hydrogen and carbon-carbon bonds (e.g. carbon tetrachloride CCl 4 ), and certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion CN , hydrogen cyanide HCN , chloroformic acid ClCO 2 H , carbon dioxide CO 2 , and carbonate ion CO 2− 3 ). Due to carbon's ability to catenate (form chains with other carbon atoms ), millions of organic compounds are known. The study of
790-560: A range of 2–12 mg/L. A single 5 gram (5000 mg) oral dose in healthy adults results in a peak plasma creatine level of approximately 120 mg/L at 1–2 hours post-ingestion. Creatine has a fairly short elimination half life, averaging just less than 3 hours, so to maintain an elevated plasma level it would be necessary to take small oral doses every 3–6 hours throughout the day. Creatine supplements are marketed in ethyl ester , gluconate , monohydrate , and nitrate forms. Creatine supplementation for sporting performance enhancement
869-474: A regulative force must exist within living bodies. Berzelius also contended that compounds could be distinguished by whether they required any organisms in their synthesis (organic compounds) or whether they did not ( inorganic compounds ). Vitalism taught that formation of these "organic" compounds were fundamentally different from the "inorganic" compounds that could be obtained from the elements by chemical manipulations in laboratories. Vitalism survived for
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#1732797833875948-452: A short period after the formulation of modern ideas about the atomic theory and chemical elements . It first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid , a compound known to occur only in living organisms, from cyanogen . A further experiment was Wöhler's 1828 synthesis of urea from the inorganic salts potassium cyanate and ammonium sulfate . Urea had long been considered an "organic" compound, as it
1027-522: A significant impact on health. Dietary fiber is not absorbed in the human digestive tract. Soluble fiber is metabolized to butyrate and other short-chain fatty acids by bacteria residing in the large intestine. Soluble fiber is marketed as serving a prebiotic function with claims for promoting "healthy" intestinal bacteria. Ethanol (C 2 H 5 OH) is not an essential nutrient, but it does supply approximately 29 kilojoules (7 kilocalories) of food energy per gram. For spirits (vodka, gin, rum, etc.)
1106-404: A single element and so not generally considered chemical compounds . The word "organic" in this context does not mean "natural". Vitalism was a widespread conception that substances found in organic nature are formed from the chemical elements by the action of a "vital force" or "life-force" ( vis vitalis ) that only living organisms possess. In the 1810s, Jöns Jacob Berzelius argued that
1185-634: A small percentage of Earth's crust , they are of central importance because all known life is based on organic compounds. Living things incorporate inorganic carbon compounds into organic compounds through a network of processes ( the carbon cycle ) that begins with the conversion of carbon dioxide and a hydrogen source like water into simple sugars and other organic molecules by autotrophic organisms using light ( photosynthesis ) or other sources of energy. Most synthetically-produced organic compounds are ultimately derived from petrochemicals consisting mainly of hydrocarbons , which are themselves formed from
1264-726: A standard serving in the United States is 44 millilitres ( 1 + 1 ⁄ 2 US fluid ounces), which at 40% ethanol (80 proof) would be 14 grams and 410 kJ (98 kcal). At 50% alcohol, 17.5 g and 513 kJ (122.5 kcal). Wine and beer contain a similar amount of ethanol in servings of 150 and 350 mL (5 and 12 US fl oz), respectively, but these beverages also contribute to food energy intake from components other than ethanol. A 150 mL (5 US fl oz) serving of wine contains 420 to 540 kJ (100 to 130 kcal). A 350 mL (12 US fl oz) serving of beer contains 400 to 840 kJ (95 to 200 kcal). According to
1343-421: A transition metal and to oxygen, and are often prepared directly from metal and carbon monoxide . Nickel tetracarbonyl is typically classified as an organometallic compound as it satisfies the broad definition that organometallic chemistry covers all compounds that contain at least one carbon to metal covalent bond; it is unknown whether organometallic compounds form a subset of organic compounds. For example,
1422-1692: A variety of ways. One major distinction is between natural and synthetic compounds. Organic compounds can also be classified or subdivided by the presence of heteroatoms , e.g., organometallic compounds , which feature bonds between carbon and a metal , and organophosphorus compounds , which feature bonds between carbon and a phosphorus . Another distinction, based on the size of organic compounds, distinguishes between small molecules and polymers . Natural compounds refer to those that are produced by plants or animals. Many of these are still extracted from natural sources because they would be more expensive to produce artificially. Examples include most sugars , some alkaloids and terpenoids , certain nutrients such as vitamin B 12 , and, in general, those natural products with large or stereoisometrically complicated molecules present in reasonable concentrations in living organisms. Further compounds of prime importance in biochemistry are antigens , carbohydrates , enzymes , hormones , lipids and fatty acids , neurotransmitters , nucleic acids , proteins , peptides and amino acids , lectins , vitamins , and fats and oils . Compounds that are prepared by reaction of other compounds are known as " synthetic ". They may be either compounds that are already found in plants/animals or those artificial compounds that do not occur naturally . Most polymers (a category that includes all plastics and rubbers ) are organic synthetic or semi-synthetic compounds. Many organic compounds—two examples are ethanol and insulin —are manufactured industrially using organisms such as bacteria and yeast. Typically,
1501-420: Is 120 mmol per kilogram of dry muscle mass, but can reach up to 160 mmol/kg through supplementation. Approximately 1–2% of intramuscular creatine is degraded per day and an individual would need about 1–3 grams of creatine per day to maintain average (unsupplemented) creatine storage. An omnivorous diet provides roughly half of this value, with the remainder synthesized in the liver and kidneys. Creatine
1580-445: Is a component of Vitamin B 12 which is essential. There are other minerals which are essential for some plants and animals, but may or may not be essential for humans, such as boron and silicon . Choline is an essential nutrient. The cholines are a family of water-soluble quaternary ammonium compounds . Choline is the parent compound of the cholines class, consisting of ethanolamine having three methyl substituents attached to
1659-559: Is a deficiency. Deficiencies can be due to several causes, including an inadequacy in nutrient intake, called a dietary deficiency, or any of several conditions that interfere with the utilization of a nutrient within an organism. Some of the conditions that can interfere with nutrient utilization include problems with nutrient absorption, substances that cause a greater-than-normal need for a nutrient, conditions that cause nutrient destruction, and conditions that cause greater nutrient excretion. Nutrient toxicity occurs when excess consumption of
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#17327978338751738-412: Is a naturally occurring non-protein compound and the primary constituent of phosphocreatine, which is used to regenerate ATP within the cell. 95% of the human body's total creatine and phosphocreatine stores are found in skeletal muscle, while the remainder is distributed in the blood , brain, testes, and other tissues. The typical creatine content of skeletal muscle (as both creatine and phosphocreatine)
1817-795: Is a nutrient required for normal physiological function that cannot be synthesized in the body – either at all or in sufficient quantities – and thus must be obtained from a dietary source. Apart from water , which is universally required for the maintenance of homeostasis in mammals, essential nutrients are indispensable for various cellular metabolic processes and for the maintenance and function of tissues and organs. The nutrients considered essential for humans comprise nine amino acids, two fatty acids, thirteen vitamins , fifteen minerals and choline . In addition, there are several molecules that are considered conditionally essential nutrients since they are indispensable in certain developmental and pathological states. An essential amino acid
1896-502: Is achieved by converting adenosine diphosphate (ADP) back to ATP via donation of phosphate groups . Creatine also acts as a buffer . Creatine was first identified in 1832 when Michel Eugène Chevreul isolated it from the basified water-extract of skeletal muscle . He later named the crystallized precipitate after the Greek word for meat, κρέας ( kreas ). In 1928, creatine was shown to exist in equilibrium with creatinine . Studies in
1975-597: Is addressed by requirements set for protein, which is composed of nitrogen-containing amino acids. Sulfur is essential, but again does not have a recommended intake. Instead, recommended intakes are identified for the sulfur-containing amino acids methionine and cysteine . The essential nutrient trace elements for humans, listed in order of Recommended Dietary Allowance (expressed as a mass), are potassium , chloride , sodium , calcium , phosphorus , magnesium , iron , zinc , manganese , copper , iodine , chromium , molybdenum , and selenium . Additionally, cobalt
2054-474: Is an accepted version of this page A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals , plants , fungi and protists . Nutrients can be incorporated into cells for metabolic purposes or excreted by cells to create non-cellular structures such as hair , scales , feathers , or exoskeletons . Some nutrients can be metabolically converted into smaller molecules in
2133-469: Is an amino acid that is required by an organism but cannot be synthesized de novo by it, and therefore must be supplied in its diet. Out of the twenty standard protein-producing amino acids, nine cannot be endogenously synthesized by humans: phenylalanine , valine , threonine , tryptophan , methionine , leucine , isoleucine , lysine , and histidine . Essential fatty acids (EFAs) are fatty acids that humans and other animals must ingest because
2212-972: Is any compound that contains a significant amount of carbon—even though many of the organic compounds known today have no connection to any substance found in living organisms. The term carbogenic has been proposed by E. J. Corey as a modern alternative to organic , but this neologism remains relatively obscure. The organic compound L -isoleucine molecule presents some features typical of organic compounds: carbon–carbon bonds , carbon–hydrogen bonds , as well as covalent bonds from carbon to oxygen and to nitrogen. As described in detail below, any definition of organic compound that uses simple, broadly-applicable criteria turns out to be unsatisfactory, to varying degrees. The modern, commonly accepted definition of organic compound essentially amounts to any carbon-containing compound, excluding several classes of substances traditionally considered "inorganic". The list of substances so excluded varies from author to author. Still, it
2291-500: Is conditional, as people who get sufficient exposure to ultraviolet light, either from the sun or an artificial source, synthesize vitamin D in the skin. Minerals are the exogenous chemical elements indispensable for life. Although the four elements: carbon , hydrogen , oxygen , and nitrogen ( CHON ) are essential for life, they are so plentiful in food and drink that these are not considered nutrients and there are no recommended intakes for these as minerals. The need for nitrogen
2370-799: Is considered safe for short-term use but there is a lack of safety data for long term use, or for use in children and adolescents. Some athletes choose to cycle on and off creatine. A 2018 review article in the Journal of the International Society of Sports Nutrition said that creatine monohydrate might help with energy availability for high-intensity exercise. Creatine use can increase maximum power and performance in high-intensity anaerobic repetitive work (periods of work and rest) by 5% to 15%. Creatine has no significant effect on aerobic endurance , though it will increase power during short sessions of high-intensity aerobic exercise. Creatine
2449-462: Is continuously and efficiently replenished from the large pools of PCr and CK. A proposed representation has been illustrated by Krieder et al. Creatine has the ability to increase muscle stores of PCr, potentially increasing the muscle's ability to resynthesize ATP from ADP to meet increased energy demands. Creatine supplementation appears to increase the number of myonuclei that satellite cells will 'donate' to damaged muscle fibers , which increases
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2528-1045: Is essential to humans and some animal species but most other animals and many plants are able to synthesize it. Nutrients may be organic or inorganic: organic compounds include most compounds containing carbon, while all other chemicals are inorganic. Inorganic nutrients include nutrients such as iron , selenium , and zinc , while organic nutrients include, protein, fats, sugars and vitamins. A classification used primarily to describe nutrient needs of animals divides nutrients into macronutrients and micronutrients . Consumed in relatively large amounts ( grams or ounces ), macronutrients (carbohydrates, fats , proteins, water) are primarily used to generate energy or to incorporate into tissues for growth and repair. Micronutrients are needed in smaller amounts ( milligrams or micrograms ); they have subtle biochemical and physiological roles in cellular processes, like vascular functions or nerve conduction . Inadequate amounts of essential nutrients or diseases that interfere with absorption, result in
2607-710: Is generally agreed upon that there are (at least) a few carbon-containing compounds that should not be considered organic. For instance, almost all authorities would require the exclusion of alloys that contain carbon, including steel (which contains cementite , Fe 3 C ), as well as other metal and semimetal carbides (including "ionic" carbides, e.g, Al 4 C 3 and CaC 2 and "covalent" carbides, e.g. B 4 C and SiC , and graphite intercalation compounds, e.g. KC 8 ). Other compounds and materials that are considered 'inorganic' by most authorities include: metal carbonates , simple oxides of carbon ( CO , CO 2 , and arguably, C 3 O 2 ),
2686-475: Is important to mention that kidneys themselves, for normal physiological function, need phosphocreatine and creatine and indeed kidneys express significant amounts of creatine kinases (BB-CK and u-mtCK isoenzymes). At the same time, the first of two steps for endogenous creatine synthesis takes place in the kidneys themselves. Patients with kidney disease and those undergoing dialysis treatment generally show significantly lower levels of creatine in their organs, since
2765-427: Is not an essential nutrient . It is an amino acid derivative , naturally produced in the human body from the amino acids glycine and arginine , with an additional requirement for S-Adenosyl methionine (a derivative of methionine ) to catalyze the transformation of guanidinoacetate to creatine. In the first step of the biosynthesis , the enzyme arginine:glycine amidinotransferase (AGAT, EC:2.1.4.1 ) mediates
2844-643: Is not sufficient information to set EARs and RDAs. PRI Population Reference Intake is European Union equivalent of RDA; higher for adults than for children, and may be even higher for women who are pregnant or lactating. For Thiamin and Niacin, the PRIs are expressed as amounts per megajoule (239 kilocalories) of food energy consumed. Upper Limit Tolerable upper intake levels. ND ULs have not been determined. NE EARs, PRIs or AIs have not yet been established or will not be (EU does not consider chromium an essential nutrient). Plant nutrients consist of more than
2923-479: Is on a carbon atom. For historical reasons discussed below, a few types of carbon-containing compounds, such as carbides , carbonates (excluding carbonate esters ), simple oxides of carbon (for example, CO and CO 2 ) and cyanides are generally considered inorganic compounds . Different forms ( allotropes ) of pure carbon, such as diamond , graphite , fullerenes and carbon nanotubes are also excluded because they are simple substances composed of
3002-504: Is proven to boost the recovery and work capacity of an athlete, and multi-applicable capabilities upon athletes have given it a lot of interest over the course of the past decade. A survey of 21,000 college athletes showed that 14% of athletes take creatine supplements to try to improve performance. Compared to normal athletes, those with creatine supplementation have been shown to produce better athletic performance. Non-athletes report taking creatine supplements to improve appearance. Creatine
3081-869: Is related to the transport of creatine into the brain. Vegan and vegetarian diets are associated with lower levels of muscle creatine, and athletes on these diets may benefit from creatine supplementation. Most of the research to-date on creatine has predominantly focused on the pharmacological properties of creatine, yet there is a lack of research into the pharmacokinetics of creatine. Studies have not established pharmacokinetic parameters for clinical usage of creatine such as volume of distribution, clearance, bioavailability, mean residence time, absorption rate, and half life. A clear pharmacokinetic profile would need to be established prior to optimal clinical dosing. An approximation of 0.3 g/kg/day divided into 4 equal spaced intervals has been suggested since creatine needs may vary based on body weight. It has also been shown that taking
3160-530: Is required with stressed populations, as supplementation does appear to significantly affect brain content. A meta-analysis found that creatine treatment increased muscle strength in muscular dystrophies , and potentially improved functional performance. Creatine treatment does not appear to improve muscle strength in people who have metabolic myopathies . High doses of creatine lead to increased muscle pain and an impairment in activities of daily living when taken by people who have McArdle disease . According to
3239-652: Is sometimes reported to have a beneficial effect on brain function and cognitive processing, although the evidence is difficult to interpret systematically and the appropriate dosing is unknown. The greatest effect appears to be in individuals who are stressed (due, for instance, to sleep deprivation ) or cognitively impaired. A 2018 systematic review found that "generally, there was evidence that short term memory and intelligence/reasoning may be improved by creatine administration", whereas for other cognitive domains "the results were conflicting". Another 2023 review initially found evidence of improved memory function. However, it
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3318-414: Is transported through the blood and taken up by tissues with high energy demands, such as the brain and skeletal muscle, through an active transport system. The concentration of ATP in skeletal muscle is usually 2–5 mM, which would result in a muscle contraction of only a few seconds. During times of increased energy demands, the phosphagen (or ATP/PCr) system rapidly resynthesizes ATP from ADP with
3397-526: Is weight gain within the first week of the supplement schedule, likely attributable to greater water retention due to the increased muscle creatine concentrations by means of osmosis . A 2009 systematic review discredited concerns that creatine supplementation could affect hydration status and heat tolerance and lead to muscle cramping and diarrhea. Despite weight gain due to water retention and potential cramps being two seemingly "common" side effects, new research indicates that these side effects are likely not
3476-520: The DNA of an organism is altered to express compounds not ordinarily produced by the organism. Many such biotechnology -engineered compounds did not previously exist in nature. A great number of more specialized databases exist for diverse branches of organic chemistry. The main tools are proton and carbon-13 NMR spectroscopy , IR Spectroscopy , Mass spectrometry , UV/Vis Spectroscopy and X-ray crystallography . Essential nutrient This
3555-490: The European Food Safety Authority recommendations in at least one contaminant. The most prevalent of these contaminants was creatinine , a breakdown product of creatine also produced by the body. Creatinine was present in higher concentrations than the European Food Safety Authority recommendations in 44% of the samples. About 15% of the samples had detectable levels of dihydro-1,3,5-triazine or
3634-679: The National Kidney Foundation investigated whether creatine supplementation had adverse effects on renal function. They identified 15 studies from 1997 to 2013 that looked at standard creatine loading and maintenance protocols of 4–20 g/day of creatine versus placebo. They utilized serum creatinine, creatinine clearance, and serum urea levels as a measure of renal damage. While in general creatine supplementation resulted in slightly elevated creatinine levels that remained within normal limits, supplementation did not induce renal damage (P value< 0.001). Special populations included in
3713-781: The allotropes of carbon, cyanide derivatives not containing an organic residue (e.g., KCN , (CN) 2 , BrCN , cyanate anion OCN , etc.), and heavier analogs thereof (e.g., cyaphide anion CP , CSe 2 , COS ; although carbon disulfide CS 2 is often classed as an organic solvent). Halides of carbon without hydrogen (e.g., CF 4 and CClF 3 ), phosgene ( COCl 2 ), carboranes , metal carbonyls (e.g., nickel tetracarbonyl ), mellitic anhydride ( C 12 O 9 ), and other exotic oxocarbons are also considered inorganic by some authorities. Nickel tetracarbonyl ( Ni(CO) 4 ) and other metal carbonyls are often volatile liquids, like many organic compounds, yet they contain only carbon bonded to
3792-402: The 1920s showed that consumption of large amounts of creatine did not result in its excretion. This result pointed to the ability of the body to store creatine, which in turn suggested its use as a dietary supplement. In 1912, Harvard University researchers Otto Folin and Willey Glover Denis found evidence that ingesting creatine can dramatically boost the creatine content of the muscle. In
3871-563: The 2019 Systematic review included type 2 diabetic patients and post-menopausal women, bodybuilders, athletes, and resistance trained populations. The study also discussed 3 case studies where there were reports that creatine affected renal function. In a joint statement between the American College of Sports Medicine , Academy of Nutrition and Dietetics , and Dietitians in Canada on performance enhancing nutrition strategies, creatine
3950-501: The European Union (same concept as RDAs), followed by what three government organizations deem to be the safe upper intake. RDAs are set higher than EARs to cover people with higher-than-average needs. Adequate Intakes (AIs) are set when there is insufficient information to establish EARs and RDAs. Countries establish tolerable upper intake levels , also referred to as upper limits (ULs), based on amounts that cause adverse effects. Governments are slow to revise information of this nature. For
4029-620: The Olympics. At the time, low-potency creatine supplements were available in Britain, but creatine supplements designed for strength enhancement were not commercially available until 1993 when a company called Experimental and Applied Sciences (EAS) introduced the compound to the sports nutrition market under the name Phosphagen . Research performed thereafter demonstrated that the consumption of high glycemic carbohydrates in conjunction with creatine increases creatine muscle stores. Creatine
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#17327978338754108-970: The U.S. Department of Agriculture, based on NHANES 2013–2014 surveys, women ages 20 and up consume on average 6.8 grams of alcohol per day and men consume on average 15.5 grams per day. Ignoring the non-alcohol contribution of those beverages, the average ethanol contributions to daily food energy intake are 200 and 450 kJ (48 and 108 kcal), respectively. Alcoholic beverages are considered empty calorie foods because, while providing energy, they contribute no essential nutrients. By definition, phytochemicals include all nutritional and non-nutritional components of edible plants. Included as nutritional constituents are provitamin A carotenoids , whereas those without nutrient status are diverse polyphenols , flavonoids , resveratrol , and lignans that are present in numerous plant foods. Some phytochemical compounds are under preliminary research for their potential effects on human diseases and health. However,
4187-546: The U.S. values, except calcium and vitamin D, all data date from 1997 to 2004. * The daily recommended amounts of niacin and magnesium are higher than the tolerable upper limit because, for both nutrients, the ULs identify the amounts which will not increase risk of adverse effects when the nutrients are consumed as a serving of a dietary supplement. Magnesium supplementation above the UL may cause diarrhea. Supplementation with niacin above
4266-459: The UL may cause flushing of the face and a sensation of body warmth. Each country or regional regulatory agency decides on a safety margin below when symptoms may occur, so the ULs may differ based on source. EAR U.S. Estimated Average Requirements. RDA U.S. Recommended Dietary Allowances; higher for adults than for children, and may be even higher for women who are pregnant or lactating. AI U.S. Adequate Intake; AIs established when there
4345-836: The amino function. Healthy humans fed artificially composed diets that are deficient in choline develop fatty liver, liver damage, and muscle damage. Choline was not initially classified as essential because the human body can produce choline in small amounts through phosphatidylcholine metabolism. Conditionally essential nutrients are certain organic molecules that can normally be synthesized by an organism, but under certain conditions in insufficient quantities. In humans, such conditions include premature birth , limited nutrient intake, rapid growth, and certain disease states. Inositol , taurine , arginine , glutamine and nucleotides are classified as conditionally essential and are particularly important in neonatal diet and metabolism. Non-essential nutrients are substances within foods that can have
4424-679: The amount of any macronutrients and micronutrients present in the food in significant quantities. Nutrients in larger quantities than the body needs may have harmful effects. Edible plants also contain thousands of compounds generally called phytochemicals which have unknown effects on disease or health including a diverse class with non-nutrient status called polyphenols which remain poorly understood as of 2024. Macronutrients are defined in several ways. Macronutrients provide energy: Micronutrients are essential dietary elements required in varying quantities throughout life to serve metabolic and physiological functions . An essential nutrient
4503-1006: The body requires them for good health but cannot synthesize them. Only two fatty acids are known to be essential for humans: alpha-linolenic acid (an omega-3 fatty acid ) and linoleic acid (an omega-6 fatty acid ). Vitamins occur in a variety of related forms known as vitamers . The vitamers of a given vitamin perform the functions of that vitamin and prevent symptoms of deficiency of that vitamin. Vitamins are those essential organic molecules that are not classified as amino acids or fatty acids. They commonly function as enzymatic cofactors , metabolic regulators or antioxidants . Humans require thirteen vitamins in their diet, most of which are actually groups of related molecules (e.g. vitamin E includes tocopherols and tocotrienols ): vitamins A, C, D, E, K, thiamine (B 1 ), riboflavin (B 2 ), niacin (B 3 ), pantothenic acid (B 5 ), pyridoxine (B 6 ), biotin (B 7 ), folate (B 9 ), and cobalamin (B 12 ). The requirement for vitamin D
4582-938: The evidence of covalent Fe-C bonding in cementite , a major component of steel, places it within this broad definition of organometallic, yet steel and other carbon-containing alloys are seldom regarded as organic compounds. Thus, it is unclear whether the definition of organometallic should be narrowed, whether these considerations imply that organometallic compounds are not necessarily organic, or both. Metal complexes with organic ligands but no carbon-metal bonds (e.g., (CH 3 CO 2 ) 2 Cu ) are not considered organometallic; instead, they are called metal-organic compounds (and might be considered organic). The relatively narrow definition of organic compounds as those containing C-H bonds excludes compounds that are (historically and practically) considered organic. Neither urea CO(NH 2 ) 2 nor oxalic acid (COOH) 2 are organic by this definition, yet they were two key compounds in
4661-539: The gold medal winner at 100 meters, had used creatine before the Olympics (however, it should also be noted that Christie was found guilty of doping later in his career). An article in Bodybuilding Monthly named Sally Gunnell , who was the gold medalist in the 400-meter hurdles, as another creatine user. In addition, The Times also noted that 100 meter hurdler Colin Jackson began taking creatine before
4740-404: The high pressure and temperature degradation of organic matter underground over geological timescales. This ultimate derivation notwithstanding, organic compounds are no longer defined as compounds originating in living things, as they were historically. In chemical nomenclature, an organyl group , frequently represented by the letter R, refers to any monovalent substituent whose open valence
4819-419: The late 1920s, after finding that the intramuscular stores of creatine can be increased by ingesting creatine in larger than normal amounts, scientists discovered phosphocreatine (creatine phosphate), and determined that creatine is a key player in the metabolism of skeletal muscle . It is naturally formed in vertebrates. The discovery of phosphocreatine was reported in 1927. In the 1960s, creatine kinase (CK)
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#17327978338754898-601: The mineral mellite ( Al 2 C 6 (COO) 6 ·16H 2 O ). A slightly broader definition of the organic compound includes all compounds bearing C-H or C-C bonds. This would still exclude urea. Moreover, this definition still leads to somewhat arbitrary divisions in sets of carbon-halogen compounds. For example, CF 4 and CCl 4 would be considered by this rule to be "inorganic", whereas CHF 3 , CHCl 3 , and C 2 Cl 6 would be organic, though these compounds share many physical and chemical properties. Organic compounds may be classified in
4977-560: The pathological kidneys are both hampered in creatine synthesis capability and are in back-resorption of creatine from the urine in the distal tubules. In addition, dialysis patients lose creatine due to wash out by the dialysis treatment itself and thus become chronically creatine depleted. This situation is exacerbated by the fact that dialysis patients generally consume less meat and fish, the alimentary sources of creatine. Therefore, to alleviate chronic creatine depletion in these patients and allow organs to replenish their stores of creatine, it
5056-404: The potential for growth of those fibers. This increase in myonuclei probably stems from creatine's ability to increase levels of the myogenic transcription factor MRF4. Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects . Clinically, there are three distinct disorders of creatine metabolism, termed cerebral creatine deficiencies . Deficiencies in
5135-701: The process of releasing energy such as for carbohydrates , lipids , proteins and fermentation products ( ethanol or vinegar ) leading to end-products of water and carbon dioxide . All organisms require water. Essential nutrients for animals are the energy sources, some of the amino acids that are combined to create proteins , a subset of fatty acids , vitamins and certain minerals . Plants require more diverse minerals absorbed through roots, plus carbon dioxide and oxygen absorbed through leaves. Fungi live on dead or living organic matter and meet nutrient needs from their host. Different types of organisms have different essential nutrients. Ascorbic acid ( vitamin C )
5214-647: The properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry . For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts ), along with a few other exceptions (e.g., carbon dioxide , and even hydrogen cyanide despite the fact it contains a carbon-hydrogen bond), are generally considered inorganic . Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only
5293-405: The qualification for nutrient status of compounds with poorly defined properties in vivo is that they must first be defined with a Dietary Reference Intake level to enable accurate food labeling, a condition not established for most phytochemicals that are claimed to provide antioxidant benefits. See Vitamin , Mineral (nutrient) , Protein (nutrient) An inadequate amount of a nutrient
5372-494: The reaction of glycine and arginine to form guanidinoacetate . This product is then methylated by guanidinoacetate N -methyltransferase (GAMT, EC:2.1.1.2 ), using S -adenosyl methionine as the methyl donor. Creatine itself can be phosphorylated by creatine kinase to form phosphocreatine , which is used as an energy buffer in skeletal muscles and the brain. A cyclic form of creatine, called creatinine , exists in equilibrium with its tautomer and with creatine. Creatine
5451-596: The research section. However, higher doses for longer periods of time are being studied to offset creatine synthesis deficiencies and mitigating diseases. After the 5–7 day loading phase, muscle creatine stores are fully saturated and supplementation only needs to cover the amount of creatine broken down per day. This maintenance dose was originally reported to be around 2–3 g/day (or 0.03 g/kg/day), however, some studies have suggested 3–5 g/day maintenance dose to maintain saturated muscle creatine. Endogenous serum or plasma creatine concentrations in healthy adults are normally in
5530-423: The result of creatine usage. In addition, the initial water retention is attributed to more short-term creatine use (the "loading" phase). Studies have shown that creatine usage does not necessarily affect total body water relative to muscle mass in the long-term. Long-term creatine supplementation has not been proven safe either in general or for people with kidney conditions. A 2019 systematic review published by
5609-518: The short duration of trials. Several primary studies have been completed but no systematic review on Huntington's disease has been completed yet. It is ineffective as a treatment for amyotrophic lateral sclerosis . A 2021 systemic review of studies found that "the current body of evidence does not indicate that creatine supplementation increases total testosterone , free testosterone , DHT or causes hair loss/baldness". Side effects include: One well-documented effect of creatine supplementation
5688-563: The two synthesis enzymes can cause L-arginine:glycine amidinotransferase deficiency caused by variants in GATM and guanidinoacetate methyltransferase deficiency , caused by variants in GAMT . Both biosynthetic defects are inherited in an autosomal recessive manner. A third defect, creatine transporter defect , is caused by mutations in SLC6A8 and is inherited in a X-linked manner. This condition
5767-517: The use of phosphocreatine (PCr) through a reversible reaction catalysed by the enzyme creatine kinase (CK). The phosphate group is attached to an NH center of the creatine. In skeletal muscle, PCr concentrations may reach 20–35 mM or more. Additionally, in most muscles, the ATP regeneration capacity of CK is very high and is therefore not a limiting factor. Although the cellular concentrations of ATP are small, changes are difficult to detect because ATP
5846-589: The vitalism debate. However, the IUPAC Blue Book on organic nomenclature specifically mentions urea and oxalic acid as organic compounds. Other compounds lacking C-H bonds but traditionally considered organic include benzenehexol , mesoxalic acid , and carbon tetrachloride . Mellitic acid , which contains no C-H bonds, is considered a possible organic compound in Martian soil. Terrestrially, it, and its anhydride, mellitic anhydride , are associated with
5925-412: Was included in their list of ergogenic aids and they do not list renal function as a concern for use. The most recent position stand on creatine from the Journal of International Society of Sports Nutrition states that creatine is safe to take in healthy populations from infants to the elderly to performance athletes. They also state that long term (5 years) use of creatine has been considered safe. It
6004-445: Was known to occur only in the urine of living organisms. Wöhler's experiments were followed by many others, in which increasingly complex "organic" substances were produced from "inorganic" ones without the involvement of any living organism, thus disproving vitalism. Although vitalism has been discredited, scientific nomenclature retains the distinction between organic and inorganic compounds. The modern meaning of organic compound
6083-425: Was later determined that faulty statistics lead to the statistical significance and after fixing the "double counting", the effect was only significant in older adults. A 2023 review study "...supported claims that creatine supplementation can increases [sic] brain creatine content but also demonstrated somewhat equivocal results for effects on cognition. It does, however, provide evidence to suggest that more research
6162-664: Was proposed in a 2017 article in Medical Hypotheses to supplement dialysis patients with extra creatine, preferably by intra-dialytic administration. Such a supplementation with creatine in dialysis patients is expected to significantly improve the health and quality of the patients by improving muscle strength, coordination of movement, brain function and to alleviate depression and chronic fatigue that are common in these patients. A 2011 survey of 33 supplements commercially available in Italy found that over 50% of them exceeded
6241-626: Was shown to phosphorylate ADP using phosphocreatine (PCr) to generate ATP. It follows that ATP - not PCr - is directly consumed in muscle contraction. CK uses creatine to "buffer" the ATP/ADP ratio. While creatine's influence on physical performance has been well documented since the early twentieth century, it came into public view following the 1992 Olympics in Barcelona . An August 7, 1992 article in The Times reported that Linford Christie ,
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