A vitamin is an organic molecule that are essential to an organism in small quantities for proper metabolic function. Essential nutrients cannot be synthesized in the organism in sufficient quantities for survival, and therefore must be obtained through the diet. For example, Vitamin C can be synthesized by some species but not by others; it is not considered a vitamin in the first instance but is in the second. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, there are eight vitamers of vitamin E: four tocopherols and four tocotrienols.
Leucine (symbol Leu or L) is an essential amino acid that is used in the biosynthesis of proteins. Leucine is an α-amino acid, meaning it contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isobutyl group, making it a non-polar aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it: it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, and beans and other legumes. It is encoded by the codons UUA, UUG, CUU, CUC, CUA, and CUG.
A dietary supplement is a manufactured product intended to supplement one's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources or that are synthetic in order to increase the quantity of their consumption. The class of nutrient compounds includes vitamins, minerals, fiber, fatty acids, and amino acids. Dietary supplements can also contain substances that have not been confirmed as being essential to life, but are marketed as having a beneficial biological effect, such as plant pigments or polyphenols. Animals can also be a source of supplement ingredients, such as collagen from chickens or fish for example. These are also sold individually and in combination, and may be combined with nutrient ingredients. The European Commission has also established harmonized rules to help insure that food supplements are safe and appropriately labeled.
Ephedrine is a central nervous system (CNS) stimulant that is often used to prevent low blood pressure during anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken by mouth or by injection into a muscle, vein, or just under the skin. Onset with intravenous use is fast, while injection into a muscle can take 20 minutes, and by mouth can take an hour for effect. When given by injection it lasts about an hour and when taken by mouth it can last up to four hours.
Life extension is the concept of extending the human lifespan, either modestly through improvements in medicine or dramatically by increasing the maximum lifespan beyond its generally-settled limit of 125 years.
B vitamins are a class of water-soluble vitamins that play important roles in cell metabolism and synthesis of red blood cells. Though these vitamins share similar names (B1, B2, B3, etc.), they are chemically distinct compounds that often coexist in the same foods. In general, dietary supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific number or name of each vitamin, such as B1 for thiamine, B2 for riboflavin, and B3 for niacin. Some are more commonly recognized by name than by number, for example pantothenic acid, biotin, and folate.
Controversies regarding the use of human growth hormone (HGH) as treatment method have centered on the claims, products, and businesses related to the use of growth hormone as an anti-aging therapy. Most of these controversies fall into two categories:
- Claims of exaggerated, misleading, or unfounded assertions that growth hormone treatment safely and effectively slows or reverses the effects of aging.
- The sale of products that fraudulently or misleadingly purport to be growth hormone or to increase the user's own secretion of natural human growth hormone to a beneficial degree.
Calorie restriction mimetics (CRM), also known as energy restriction mimetics, are a hypothetical class of dietary supplements or drug candidates that would, in principle, mimic the substantial anti-aging effects that calorie restriction (CR) has on many laboratory animals and humans. CR is defined as a reduction in calorie intake of 20% to 50% without incurring malnutrition or a reduction in essential nutrients. An effective CRM would alter the key metabolic pathways involved in the effects of CR itself, leading to preserved youthful health and longer lifespan without the need to reduce food intake. The term was coined by Lane, Ingram, Roth of the National Institute on Aging in a seminal 1998 paper in the Journal of Anti-Aging Medicine, the forerunner of Rejuvenation Research. A number of genes and pathways have been shown to be involved with the actions of CR in model organisms and these represent attractive targets for drug discovery and for developing CRM. However, no effective CRM have been identified to date.
Nootropics are numerous natural, semi-synthetic and synthetic molecules that claim to improve cognitive functions.
Yohimbine, also known as quebrachine, is an indole alkaloid derived from the bark of the African tree Pausinystalia johimbe; also from the bark of the unrelated South American tree Aspidosperma quebracho-blanco. Yohimbine is an α2-adrenergic receptor antagonist, and has been used in a variety of research projects. It is a veterinary drug used to reverse sedation in dogs and deer.
Aniracetam, also known as N-anisoyl-2-pyrrolidinone, is a racetam which is sold in Europe as a prescription drug. It is not approved by the Food and Drug Administration for use in the United States as a prescription medication or dietary supplement. Despite the FDA's lack of approval, the drug is readily available over-the-counter in the US as a dietary supplement.
Dimethylethanolamine is an organic compound with the formula (CH3)2NCH2CH2OH. It is bifunctional, containing both a tertiary amine and primary alcohol functional groups. It is a colorless viscous liquid. It is used in skin care products for improving skin tone and also taken orally as a nootropic. It is prepared by the ethoxylation of dimethylamine.
Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. Bodybuilding supplements may contain ingredients that are advertised to increase a person's muscle, body weight, athletic performance, and decrease a person's percent body fat for desired muscle definition. Among the most widely used are high protein drinks, pre-workout blends, branched-chain amino acids (BCAA), glutamine, arginine, essential fatty acids, creatine, HMB, whey protein, ZMA, and weight loss products. Supplements are sold either as single ingredient preparations or in the form of "stacks" – proprietary blends of various supplements marketed as offering synergistic advantages.
The vitamin E family comprise four tocotrienols and four tocopherols. The critical chemical structural difference between tocotrienols and tocopherols is that tocotrienols have unsaturated isoprenoid side chains with three carbon-carbon double bonds versus saturated side chains for tocopherols.
Prasterone, also known as dehydroepiandrosterone (DHEA) and sold under the brand names Intrarosa, Diandrone, and Gynodian Depot among others, is a medication as well as over-the-counter dietary supplement which is used to correct DHEA deficiency due to adrenal insufficiency or old age, as a component of menopausal hormone therapy, to treat painful sexual intercourse due to vaginal atrophy, and to prepare the cervix for childbirth, among other uses. It is taken by mouth, by application to the skin, in through the vagina, or by injection into muscle.
Vinpocetine is a synthetic derivative of the vinca alkaloid vincamine, differing by the removal of a hydroxyl group. Vincamine is extracted from either the seeds of Voacanga africana or the leaves of Vinca minor.
Muscle atrophy is the loss of skeletal muscle mass. It can be caused by immobility, aging, malnutrition, medications, or a wide range of injuries or diseases that impact the musculoskeletal or nervous system. Muscle atrophy leads to muscle weakness and causes disability.
Chlordiazepoxide, trade name Librium among others, is a sedative and hypnotic medication of the benzodiazepine class; it is used to treat anxiety, insomnia and symptoms of withdrawal from alcohol and other drugs.
Performance-enhancing substances, also known as performance-enhancing drugs (PEDs), are substances that are used to improve any form of activity performance in humans. A well-known example of cheating in sports involves doping in sport, where banned physical performance-enhancing drugs are used by athletes and bodybuilders. Athletic performance-enhancing substances are sometimes referred as ergogenic aids. Cognitive performance-enhancing drugs, commonly called nootropics, are sometimes used by students to improve academic performance. Performance-enhancing substances are also used by military personnel to enhance combat performance.
Ageing or aging is the process of becoming older. The term refers mainly to humans, many other animals, and fungi, whereas for example, bacteria, perennial plants and some simple animals are potentially biologically immortal. In a broader sense, ageing can refer to single cells within an organism which have ceased dividing, or to the population of a species.
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