Glossary

What Is Coenzyme Q10? Coenzyme Q10 is also known as ubiquinone-10, ubiquinone, or Q10. It is a molecule that is essential for the function of numerous proteins. It can be thought of as an electron carrier for larger proteins, as it transports electrons and protons between proteins that generate energy from the food we consume. Since humans produce approximately 95% of their energy through this process, Q10 has become a major focus of scientific research. In particular, researchers are investigating Q10 deficiency and the effects of Q10 supplementation. Scientists are also examining whether Q10 supplementation may be beneficial in the treatment and prevention of conditions such as heart attack, stroke, and Parkinson's disease. Where Does Coenzyme Q10 Naturally Occur? Q10 possesses a fat-soluble (lipophilic) side chain. This enables the quinone derivative to position itself precisely where it is needed to perform its function as an electron carrier. It anchors itself within the mitochondrial membrane—the membrane of the cell's powerhouses. Every cell in the human body contains mitochondria, which convert fatty acids and glucose into usable energy.Q10 is an endogenous substance produced naturally by the body. Although we also obtain it through food, this contribution is relatively small. Assuming the body requires approximately 500 mg of Q10 per day, only about 5 mg—or roughly 1%—is supplied through the diet. Organs with the highest energy demands also contain the highest concentrations of Q10, including the heart, brain, muscles, and lungs. On a per-gram basis, the liver contains the highest concentration of Q10 and appears to be the primary site of Q10 biosynthesis.Q10 supplementation has attracted considerable interest because reduced Q10 concentrations in the blood and cells are associated with various diseases. The reasons for impaired production or deficiency are not yet fully understood. What is well established, however, is that the body's Q10 production peaks at around 25 years of age and declines by approximately 50% by the age of 65. What Is the Primary Function of Coenzyme Q10 in the Body? Coenzyme Q10 is an essential component of the respiratory chain. It is called the respiratory chain because the process depends on oxygen, and a chain because it consists of a sequence of reactions that occur one after another. More specifically, it is an electron transport chain in which electrons are transferred to ultimately produce adenosine triphosphate (ATP), the body's universal energy currency. Q10 functions as the molecule that transfers electrons between individual reactions within this chain.In simplified terms, mitochondria use the respiratory chain to convert glucose into carbon dioxide, water, and energy (ATP) with the help of oxygen. This process explains why we inhale oxygen and exhale carbon dioxide. The respiratory chain therefore converts energy from food into biologically usable energy in the form of ATP. Q10 transfers this energy between two consecutive steps of the chain.As remarkable as the respiratory chain is, it also produces reactive oxygen species (ROS) as by-products. These free radicals oxidize cellular components such as membranes and DNA, causing oxidative damage. ROS are the reason antioxidants such as vitamin C and vitamin E are so important. Antioxidants reduce oxidative stress by neutralizing these reactive molecules before they can damage sensitive cellular structures. In doing so, they help prevent the accumulation of damage that may ultimately contribute to disease.Q10 also plays a vital role in this process. It helps protect mitochondrial membranes and the proteins embedded within them from oxidative damage. Thus, Q10 is not only essential for efficient energy metabolism but also serves as an important antioxidant. In addition, it helps regenerate other antioxidants after they have been oxidized and used by the body. What Are the Benefits of Coenzyme Q10 Supplementation? Studies have shown that individuals with certain diseases and health conditions often exhibit low blood levels of Q10. These conditions include type 2 diabetes, cardiovascular diseases, and neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Other factors associated with reduced Q10 levels include smoking and physical inactivity. Declining Q10 concentrations have also been linked to biological aging, muscle loss, and reduced muscle function.These observations have led to the hypothesis that Q10 supplementation may be beneficial both for treating existing diseases and for helping to prevent the development of various health conditions. Today, sufficient randomized controlled clinical trials are available in several areas, allowing researchers to systematically investigate the role of Q10—particularly supplemental Q10—in human health.Authors of several meta-analyses have reported evidence supporting beneficial effects of Q10 supplementation. Positive outcomes have been observed with regard to longevity, muscle function, and inflammatory markers. Q10 has also shown potential in reducing fatigue associated with disease or medication side effects, as well as in conditions such as Parkinson's disease, migraine, and acute heart failure.However, recommendations are often differentiated according to individual circumstances. It is considered highly likely that people diagnosed with Q10 deficiency syndrome or with confirmed low Q10 levels benefit from supplementation. Whether otherwise healthy individuals without a history of Q10 deficiency also benefit remains less clear. Ongoing clinical trials with improved study designs and larger participant populations are expected to provide more definitive answers. References Further information and scientific studies on the active ingredient Coenzyme Q10 can be found here. Disorders of Human Coenzyme Q10 Metabolism: An Overviewwww.ncbi.nlm.nih.gov/pmc/articles/PMC7555759 Coenzyme Q10 for Heart Failurewww.pubmed.ncbi.nlm.nih.gov/35608922 Coenzyme Q10 Supplementation in Aging and Diseasewww.ncbi.nlm.nih.gov/pmc/articles/PMC5807419 Effects of Coenzyme Q10 Supplementation on Inflammatory Markers: A Systematic Review and Meta-Analysis of Randomized Controlled Trialswww.pubmed.ncbi.nlm.nih.gov/28179205 Coenzyme Q10 and Male Infertility: A Systematic Reviewwww.pubmed.ncbi.nlm.nih.gov/34070761 Coenzyme Q10 as Adjunctive Therapy for Cardiovascular Disease and Hypertension: A Systematic Reviewwww.pubmed.ncbi.nlm.nih.gov/35348726 Coenzyme Q10 to Manage Chronic Heart Failure with a Reduced Ejection Fraction: A Systematic Review and Economic Evaluationwww.pubmed.ncbi.nlm.nih.gov/35076012 Effects of Coenzyme Q10 on Statin-Induced Myopathy: An Updated Meta-Analysis of Randomized Controlled Trialswww.pubmed.ncbi.nlm.nih.gov/30371340

What Is Pterostilbene? Pterostilbene is a stilbenoid closely related to the well-known compound resveratrol and exhibits comparable beneficial effects on the human body. Due to subtle structural differences, however, the bioavailability of pterostilbene is approximately four times higher than that of resveratrol. For this reason, pterostilbene is sometimes referred to as the "better resveratrol." Where Does Pterostilbene Naturally Occur? Pterostilbene occurs naturally in various foods, including almonds, grapes, and blueberries, where it is the primary antioxidant. Plants produce this compound in response to attacks by bacteria, viruses, or fungi. Pterostilbene is found predominantly in the skin or peel of plants and possesses antioxidant and antimicrobial properties that help defend the plant against pathogens. What Is the Primary Function of Pterostilbene in the Body? Stilbenes such as pterostilbene are produced exclusively by plants. The only known exception is a stilbene synthesized by a specific bacterial species. Humans consume these compounds through their diet, and it is assumed that this is how stilbenes exert their biological effects within the body. Numerous studies using both in vitro and in vivo models indicate that the antioxidant properties of pterostilbene may contribute to the prevention and treatment of diseases such as cancer, diabetes, and cardiovascular disease. For example, blueberry extracts containing pterostilbene have been shown in experimental studies to inhibit the growth and metastasis of breast cancer cells, esophageal cancer, and colorectal cancer, and even to protect the offspring of mice from developing cancer. Several studies have also demonstrated cardioprotective effects of pterostilbene-rich blueberries, suggesting that their enhanced antioxidant capacity may help reduce the progression of atherosclerosis. Furthermore, the blood glucose-lowering effects observed with blueberries are believed to be largely attributable to pterostilbene, which has reduced average blood glucose levels by more than 50% and substantially lowered the blood marker HbA1c in experimental studies. Benefits May be absorbed more efficiently than resveratrol May reduce the formation of reactive oxygen species May help prevent oxidative stress What Are the Benefits of Pterostilbene Supplementation? Pterostilbene is of particular interest because it exhibits biological effects similar to those of resveratrol while being absorbed much more efficiently by the body. It demonstrates comparable anti-inflammatory, antioxidant, and anticancer properties, yet its bioavailability is approximately four times higher than that of other stilbenes such as resveratrol. Preclinical studies suggest that pterostilbene may reduce the formation of reactive oxygen species while simultaneously increasing the availability of endogenous antioxidants such as glutathione. In this way, supplementation may help maintain the balance between reactive oxygen species and antioxidant capacity, thereby preventing oxidative stress and potentially reducing the risk of many chronic diseases. At the same time, pterostilbene exerts numerous additional—and in some cases highly complex—biological effects that may help prevent chronic diseases. For example, in laboratory studies involving cancer cells, pterostilbene induced programmed cell death (apoptosis). In contrast, in studies of atherosclerosis, it prevented the programmed death of vascular cells, thereby helping to inhibit plaque formation. The key question remains whether these laboratory findings can be translated into meaningful clinical effects in humans. In one study involving participants with elevated blood lipid levels, treatment with pure pterostilbene unexpectedly increased LDL cholesterol levels while simultaneously decreasing HDL cholesterol concentrations. Resveratrol has been recognized as safe by the U.S. Food and Drug Administration (FDA) since 2007. More recently, several clinical studies have also suggested that pterostilbene is safe at daily doses of up to 250 mg. References Further information and scientific studies on the active ingredient pterostilbene can be found here. A Review of Pterostilbene Antioxidant Activity and Disease Modificationwww.ncbi.nlm.nih.gov/pmc/articles/PMC3649683 Blackberry, Black Raspberry, Blueberry, Cranberry, Red Raspberry, and Strawberry Extracts Inhibit Growth and Stimulate Apoptosis of Human Cancer Cells In Vitrowww.pubmed.ncbi.nlm.nih.gov/17147415 Development of a Reversed-Phase High-Performance Liquid Chromatography Method Based on the Use of Cyclodextrins as Mobile Phase Additives to Determine Pterostilbene in Blueberrieswww.pubmed.ncbi.nlm.nih.gov/21482204 Identification of Pterostilbene as a Phytoalexin from Vitis vinifera Leaveswww.sciencedirect.com/science/article/abs/pii/S0031942200914705 Pharmacokinetics, Oral Bioavailability, and Metabolic Profile of Resveratrol and Its Dimethyl Ether Analog, Pterostilbene, in Ratswww.pubmed.ncbi.nlm.nih.gov/21116625 Analysis of Safety from a Human Clinical Trial with Pterostilbenewww.pubmed.ncbi.nlm.nih.gov/23431291

What Is Pantethine? Pantethine is considered the most active form of vitamin B5. It consists of two pantetheine units, each of which contains one molecule of pantothenic acid (vitamin B5). It was first isolated chemically by Feodor Lynen in 1951.Pantethine is important for the function of many enzymes involved in fat and energy metabolism. In studies, pantethine supplementation helped lower cholesterol levels in people with an increased risk of cardiovascular disease and impaired lipid metabolism. Where Does Pantethine Occur Naturally? Pantethine occurs in animal organisms, where it is formed from pantothenic acid. In the body, pantethine plays a central role in the formation of coenzyme A.Pantethine is widely present as a molecule in the body, while vitamin B5—the component from which pantethine is formed—is also found in many foods. Higher concentrations occur in foods such as meat, eggs, potatoes, grains, tomatoes and broccoli. Pantethine can also be produced by chemical synthesis. What Is Pantethine’s Primary Function in the Body? Pantethine is important for the formation of coenzyme A, which in turn is essential for the activity of approximately 4% of all enzymes in the body. Coenzyme A is involved in the metabolism of the macronutrients fat, protein and carbohydrate and contributes to energy production. In these processes, coenzyme A acts as a carrier of acyl groups: as acyl-coenzyme A it participates in fat metabolism, while acetyl-coenzyme A is involved in the metabolism of proteins and carbohydrates.Acyl-coenzyme A is involved in the breakdown of fatty acids through beta-oxidation. However, the molecule is formed in the cytosol, the fluid interior of the cell, and must first be transported into the mitochondria before the fatty acids can be broken down. This transport process helps explain why L-carnitine has been investigated as a supplement for weight or fat loss: acyl groups are transferred to L-carnitine for transport into the mitochondria.Coenzyme A is also important for metabolic recycling. Acetyl-coenzyme A is generated during cellular respiration, during the breakdown of amino acids such as alanine, valine and methionine, and during fatty-acid degradation. Coenzyme A molecules can then be reused in other metabolic processes, including the citric acid cycle and the synthesis of additional compounds. Because coenzyme A contains a sulfur group supplied by pantethine, it can form so-called high-energy bonds. The body uses these bonds in anabolic processes to synthesize substances such as triglycerides, ketone bodies and cholesterol. What Are the Potential Benefits of Pantethine Supplementation? Each pantethine molecule contains two units derived from pantothenic acid (vitamin B5). In line with the roles of vitamin B5, pantethine and coenzyme A in the body, the European Food Safety Authority (EFSA) has concluded that vitamin B5 contributes to normal energy-yielding metabolism, normal mental performance, the reduction of tiredness and fatigue, and the normal synthesis and metabolism of steroid hormones, vitamin D and certain neurotransmitters.Reported symptoms of vitamin B5 deficiency include restlessness, fatigue, sleep disturbances and muscle cramps. However, deficiency has so far been observed mainly under artificial experimental conditions, for example after administration of an antagonist, rather than in dietary studies.In several clinical studies, higher doses of pantethine reduced LDL cholesterol by an average of approximately 20% and triglycerides by approximately 33% in people with elevated blood lipids. At the same time, levels of “good” HDL cholesterol increased. To achieve these effects, researchers generally used an average daily dose of 900 mg of pantethine over a study period of four months.Because these studies reported favorable effects in people with cholesterol levels of at least 200 mg/dL and triglyceride levels above 150 mg/dL, pantethine supplements are typically dosed much more highly than standard vitamin B5 supplements. Vitamin B5 products often provide around 5–10 mg, whereas pantethine products may provide approximately 500–1,000 mg per day.Pantethine appears to have a generally favorable tolerability profile. The authors of one study reported no obvious adverse effects associated with its use. A review found that approximately 1% of participants experienced mild gastrointestinal complaints. In one clinical study involving children, pantethine was well tolerated at a dose of 60 mg per kilogram of body weight per day—equivalent to 3,600 mg for a person weighing 60 kilograms. Sources Further information and studies on pantethine can be found in the sources below. The effects of pantethine on fatty liver and fat distributionwww.pubmed.ncbi.nlm.nih.gov/11425046 Biosynthesis of Pantothenic Acid and Coenzyme Awww.ncbi.nlm.nih.gov/pmc/articles/PMC4950986 Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Cholinewww.pubmed.ncbi.nlm.nih.gov/23193625 Coenzyme A: back in actionwww.pubmed.ncbi.nlm.nih.gov/15893380 Pantethine, a derivative of vitamin B5, favorably alters total, LDL and non-HDL cholesterol in low to moderate cardiovascular risk subjects eligible for statin therapy: a triple-blinded placebo and diet-controlled investigationwww.ncbi.nlm.nih.gov/pmc/articles/PMC3942300

What Is Nicotinamide Riboside? Nicotinamide riboside (NR) is a form of vitamin B3 and a precursor of nicotinamide adenine dinucleotide, or NAD+. NAD+ is essential for mitochondrial energy metabolism and many cellular enzyme reactions. Research is investigating whether increasing NAD+ availability through NR can influence metabolic and age-related processes. Where Does Nicotinamide Riboside Occur Naturally? Nicotinamide riboside occurs naturally in yeasts, bacteria and mammals. Its concentration in foods has not been characterized comprehensively. Trace amounts have been reported in milk and may also occur in foods involving yeast.Researchers assume that dietary concentrations are low. The development of reliable chemical production methods made it possible to study standardized NR preparations in greater detail and to use them in food supplements. What Is Nicotinamide Riboside’s Primary Function in the Body? Nicotinamide riboside is converted through several enzymatic steps into NAD+. The reduced form is NADH. Together, NAD+ and NADH transfer electrons in metabolic reactions and contribute to ATP production in the mitochondrial respiratory chain.NAD+ is indispensable for aerobic energy production from nutrients, including glucose, fatty acids and amino acids. These pathways generate ATP, the principal immediately usable energy carrier of cells. The body can synthesize NAD+ from several vitamin B3 precursors, and nicotinamide riboside is one of these precursors. What Are the Potential Benefits of Nicotinamide Riboside Supplementation? NR is of scientific interest for two main reasons. First, NAD+ availability can decline with age and metabolic stress. Second, supplementation with NAD+ precursors can raise NAD+ metabolites in blood and tissues, although the resulting clinical benefits are still being investigated.Age-related changes in NAD metabolism may affect mitochondrial energy production and enzymes that depend on NAD+. These enzymes include sirtuins, poly(ADP-ribose) polymerases and other proteins involved in metabolic regulation, cellular stress responses and DNA repair.Sirtuins are one example of NAD+-dependent enzymes. They regulate processes including metabolic adaptation, gene expression, DNA maintenance and cellular responses to stress. Researchers are studying whether reduced NAD+ availability can limit sirtuin activity and thereby contribute to age-associated dysfunction.Human studies show that NR can increase NAD+-related metabolites. Effects on insulin sensitivity, mitochondrial function, muscle performance, inflammation and other clinical outcomes have been inconsistent or modest, and larger long-term trials are still needed.NR has been evaluated as a food ingredient and has generally shown good tolerability in clinical studies at the doses investigated. This does not mean that it is appropriate for everyone. People with medical conditions, pregnant or breastfeeding individuals and those taking medication should seek professional advice before use. Sources Further information and scientific studies on nicotinamide riboside can be found below. Nicotinamide riboside, a trace nutrient in foods, is a vitamin B3 with effects on energy metabolism and neuroprotectionwww.pubmed.ncbi.nlm.nih.gov/24071780 NAD+ and sirtuins in aging and diseasewww.pubmed.ncbi.nlm.nih.gov/24786309 Nicotinic acid, nicotinamide, and nicotinamide riboside: a molecular evaluation of NAD+ precursor vitamins in human nutritionwww.pubmed.ncbi.nlm.nih.gov/18429699 Declining NAD(+) induces a pseudohypoxic state disrupting nuclear-mitochondrial communication during agingwww.pubmed.ncbi.nlm.nih.gov/24360282

What alpha-lipoic acid is, its role in mitochondrial energy metabolism and why it is regarded as an antioxidant.

What Is N-Acetylcysteine? N-acetylcysteine is widely known as a cough suppressant and mucus-dissolving agent under the brand name ACC. Acetylcysteine is the abbreviated form of the name N-acetyl-L-cysteine, commonly referred to as NAC. The value of NAC as a dietary supplement is based on the amino acid cysteine it contains.Cysteine is a building block of many proteins in the body and, through its sulfur group, stabilizes the three-dimensional structure of biological molecules. Cysteine is particularly important as a building block of glutathione. Glutathione is a universal antioxidant and detoxification system found in every cell of the body. Where Does N-Acetylcysteine Naturally Occur? Acetylcysteine is a synthetically produced compound derived from the amino acid L-cysteine and does not occur naturally. Cysteine itself accounts for approximately 2.5% of the protein content in natural dietary proteins. Only the L-form occurs in proteins, whereas the enantiomer D-cysteine does not. Therefore, all subsequent references to cysteine refer exclusively to the L-form.When acetylcysteine is taken orally, the liver removes the acetyl group, leaving the amino acid cysteine. Cysteine is a proteinogenic, non-essential amino acid that the body uses to synthesize its own proteins.A unique feature of cysteine is its sulfur content. Only two amino acids—methionine and cysteine—contain a sulfur atom in their side chain. This enables cysteine to form so-called disulfide bridges. As the name suggests, two sulfur atoms (sulfides) from two molecules join to form a strong chemical bond. Disulfide bridges are among the strongest chemical bonds in biology, making cysteine essential for the structural stability of numerous proteins and enzymes. What Is the Primary Function of N-Acetylcysteine in the Body? By taking acetylcysteine, the body gains access to cysteine. Cysteine is an essential building block of glutathione, which also consists of glutamic acid and glycine. Every cell in the human body contains glutathione, which acts as a buffer against oxidative stress. When oxidative stress caused by reactive oxygen species (ROS) becomes excessive, glutathione neutralizes these molecules by becoming oxidized itself. In doing so, it protects other cellular structures—such as mitochondrial membranes—from oxidative damage. The body subsequently regenerates glutathione through energy-dependent processes, restoring its protective function. The sulfur group of acetylcysteine—or more precisely of cysteine—plays a decisive role in glutathione's biological activity. Through this sulfur group, glutathione supports the body's detoxification processes. Chemically, the sulfur group is highly reactive, enabling it to attack, bind, and open other compounds and molecules. Glutathione utilizes this property of its cysteine component to neutralize toxic substances within the body. It binds toxins via the sulfur group, thereby reducing the toxicity of substances such as heavy metals, pesticides, and environmental pollutants. At the same time, this process increases their water solubility, allowing the body to eliminate these toxins more efficiently through the kidneys and urine. What Are the Benefits of N-Acetylcysteine Supplementation? Physicians use the detoxifying properties of acetylcysteine and glutathione to treat acetaminophen (paracetamol) poisoning. During the breakdown of acetaminophen by cytochrome P450 enzymes in the liver, a toxic metabolite is produced that damages liver cells. This becomes particularly dangerous when recommended daily doses are exceeded and the body's glutathione stores become depleted. Glutathione binds this toxic acetaminophen metabolite and facilitates its elimination through the urine. When taken orally, acetylcysteine is intended to dissolve thick mucus and relieve coughing. The mucus produced in the bronchi consists largely of polysaccharides that are held together by disulfide bonds. Because acetylcysteine contains a sulfur group through its cysteine component, it can break these existing disulfide bonds. In this way, acetylcysteine is believed to liquefy mucus and promote expectoration. However, scientific evidence supporting this mechanism remains inconclusive. An alternative explanation for its beneficial effects on coughing is its anti-inflammatory activity. Through its sulfur group, acetylcysteine can bind free radicals that would otherwise cause oxidative damage and activate pro-inflammatory transcription factors. Longevity researchers assume that mitochondrial dysfunction and excessive oxidative stress within cells contribute to premature aging. These factors increase the risk of chronic diseases such as cancer, type 2 diabetes, and atherosclerosis. Glutathione helps maintain the natural balance of reactive oxygen species (ROS) within cells. It contributes to preserving mitochondrial function and reducing the risk of ROS-related diseases. The bioavailability of conventionally administered oral glutathione is relatively low. Oral acetylcysteine therefore provides an effective strategy for increasing the body's own glutathione stores by supplying its essential precursor, cysteine. Particularly popular—and supported by several randomized clinical trials—is the combination of NAC with glycine, another important building block of glutathione. When taken orally, acetylcysteine is considered non-toxic. The therapeutic dosage ranges from 0.4 g to 0.6 g per day. According to the European Food Safety Authority (EFSA), exceeding this dosage may cause gastrointestinal discomfort in sensitive individuals. In the past, intravenous administration of acetylcysteine has occasionally resulted in overdosing and serious adverse reactions. References Further information and scientific studies on the active ingredient N-acetylcysteine can be found here. Bioavailability Study of an Innovative Orobuccal Formulation of Glutathionewww.ncbi.nlm.nih.gov/pmc/articles/PMC4663342 Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food (AFC) on a Request from the Commission Related to N-Acetyl-L-Cysteine for Use in Foods for Particular Nutritional Uses and in Foods for Special Medical Purposeswww.efsa.europa.eu/en/efsajournal/pub/21 Effects of N-Acetylcysteine, Oral Glutathione (GSH), and a Novel Sublingual Form of GSH on Oxidative Stress Markers: A Comparative Crossover Studywww.ncbi.nlm.nih.gov/pmc/articles/PMC4536296 N-Acetylcysteine Mucolysis in the Management of Chronic Obstructive Pulmonary Diseasewww.pubmed.ncbi.nlm.nih.gov/22361928 N-Acetylcysteine—A Safe Antidote for Cysteine/Glutathione Deficiencywww.sciencedirect.com/science/article/abs/pii/S1471489207000896 Oxidative Stress and Exceptional Human Longevity: A Systematic Reviewwww.pubmed.ncbi.nlm.nih.gov/31550529 Supplementing Glycine and N-Acetylcysteine (GlyNAC) in Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, and Hallmarks of Aging: A Randomized Clinical Trialwww.pubmed.ncbi.nlm.nih.gov/35975308 Oxidative Stress and Low Glutathione in Common Ear, Nose, and Throat Conditions: A Systematic Reviewwww.pubmed.ncbi.nlm.nih.gov/27622960