Nutrition

thumb|class=skin-invert-image|upright=1.25|Lactose is a [[disaccharide found in animal milk. It consists of a molecule of D-galactose and a molecule of D-glucose bonded by beta-1-4 glycosidic linkage.]]

Obesity is a medical condition, considered by multiple organizations to be a disease, in which excess body fat has accumulated to such an extent that it can have negative effects on health. People are classified as obese when their body mass index (BMI)—a person's weight divided by the square of the person's height—is over ; the range is defined as overweight. Some East Asian countries use lower values to calculate obesity. Obesity is a major cause of disability and is correlated with various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apne

Vitamins are organic molecules (or a set of closely related molecules called vitamers) that are essential to an organism in small quantities for proper metabolic function. These essential nutrients cannot be synthesized in the organism in sufficient quantities for survival, and therefore must be obtained through consumption. 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 vit

Glucose is a sugar with the molecular formula . It is the most abundant monosaccharide, a subcategory of carbohydrates. It is made from water and carbon dioxide during photosynthesis by plants and most algae. It is used by plants to make cellulose, the most abundant carbohydrate in the world, for use in cell walls, and by all living organisms to make adenosine triphosphate (ATP), which is used by the cell as energy. Glucose is often abbreviated as Glc.

Cholesterol is the principal sterol of all animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.

thumb|Structure of the amylose molecule thumb|Structure of the amylopectin molecule

thumb|288px|Amandines de Provence, poster by Leonetto Cappiello, 1900, which shows a woman eating almond cookies

Fructose (), or fruit sugar, is a common monosaccharide, i.e. a simple sugar. It is classified as a reducing hexose, more specifically a ketonic simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. A white, water-soluble solid, it is one of the three dietary monosaccharides, along with glucose and galactose. Fructose is found in honey, tree and vine fruits, flowers, berries, and most root vegetables.

thumb|upright=1.5|alt=see caption|A purple leaf blue butterfly (Amblypodia anita) gathering [[nutrients from guano]]

thumb|upright=1.25|Schematic two-dimensional cross-sectional view of glycogen: A core protein of glycogenin is surrounded by branches of [[glucose units. The entire globular granule may contain around 30,000 glucose units.]] thumb|A view of the atomic structure of a single branched strand of [[glucose units in a glycogen molecule.]]

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 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

In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers.

right|thumb|upright=1.30|Examples of sources of gluten (clockwise from top): wheat as flour, spelt, barley, and rye as rolled flakes

indigestible portion of food derived from plants

thumb|Representative chemical structure of a tannic acid, a type of tannin thumb|Tannin powder (mixture of compounds) thumb|A bottle of tannic acid solution in [[water ]]

Galactose (, galacto- + -ose, sometimes abbreviated Gal), is a common monosaccharide, i.e. a simple sugar. It is classified as a reducing hexose, more specifically an aldohexose. In terms of structure, it is a C-4 epimer of glucose. A white, water-soluble solid, it is about 80–90% as sweet as glucose and about 65% as sweet as sucrose.

Flavonoids (or bioflavonoids; from the Latin word flavus, meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants. Blackberry, black currant, chokeberry, and red cabbage are examples of plants with rich contents of flavonoids. In plant biology, flavonoids fulfill diverse functions, including attraction of pollinating insects, antioxidant protection against ultraviolet light, deterrence of environmental stresses and pathogens, and regulation of cell growth.

thumb|Statue drinking from a traditional waterskin|alt=Statue of a man drinking|upright=1.2 thumb|upright|A person drinking a glass of milk

type of unsaturated fat that occurs in small amounts in nature, but is also produced industrially from vegetable fats for use in foods

An oligosaccharide (; ) is a saccharide polymer containing a small number (typically three to ten) of monosaccharides (simple sugars). Oligosaccharides can have many functions including cell recognition and cell adhesion.

amino acid that cannot be synthesized de novo by the organism

chemical compound

fat in which the fatty acid chains have all or predominantly single bonds

chemical energy that animals (including humans) derive from food and molecular oxygen through the process of cellular respiration

Ergosterol (ergosta-5,7,22-trien-3β-ol) is a mycosterol found in cell membranes of fungi and protozoa, serving many of the same functions that cholesterol serves in animal cells. Because many fungi and protozoa cannot survive without ergosterol, the enzymes that synthesize it have become important targets for drug discovery. In human nutrition, ergosterol is a provitamin form of vitamin D2; exposure to ultraviolet (UV) light causes a chemical reaction that produces vitamin D2.

chemical element whose concentration (or other measure of amount) is very low

thumb|Effects of trace element malnutrition on human health Micronutrients are essential chemicals required by organisms in small quantities to perform various biogeochemical processes and regulate physiological functions of cells and organs. By enabling these processes, micronutrients support the health of organisms throughout life.

A phytoestrogen is a plant-derived xenoestrogen (a type of estrogen produced by organisms other than humans) not generated within the endocrine system, but consumed by eating plants or manufactured foods. Also called a "dietary estrogen", it is a diverse group of naturally occurring nonsteroidal plant compounds that, because of its structural similarity to estradiol (17-β-estradiol), have the ability to cause both estrogenic or antiestrogenic effects.

thumb|Red, blue, and purple colors of berries derive mainly from polyphenol phytochemicals called [[anthocyanins.]] thumb|Cucurbita fruits, including squash and [[pumpkin, typically have high content of the phytochemical pigments called carotenoids.]]

fat or fatty acid in which there is at least one double bond within the fatty acid chain

amino acid that is incorporated biosynthetically into proteins during translation

Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.

type of processed food characterized by cheap ingredients and design for consumer appeal

Alliin is a sulfoxide that is a natural constituent of fresh garlic. It is a derivative of the amino acid cysteine. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. Allicin and other thiosulfinates in garlic are unstable and form a number of other compounds, such as diallyl sulfide (DAS), diallyl disulfide (DADS) and diallyl trisulfide (DAT), dithiins and ajoene. Garlic powder is not a source of alliin, nor is fresh garlic upon maceration, since the enzymatic conversion to allicin takes place in the

illness caused by sudden refeeding of a malnourished individual

measure

chemical compound acting as osmotic regulator in marine organisms and fishes

thumb|250px|right|The epidermal strata of the skin

thumb|Technicians harvesting different types of microgreens for shelf-life studies and [[nutrient analyses]] Microgreens are vegetable greens (not to be confused with sprouts or shoots) harvested just after the cotyledon leaves have developed with one set of true leaves. They are used as a visual, flavor and texture enhancement. thumb Microgreens are used to add sweetness and spiciness to foods. Microgreens are smaller than "baby greens" because they are harvested soon after sprouting, rather than after the plant has matured to produce multiple leaves.

thumb|right|250px|Glucosinolate structure; side group R varies. Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. These natural chemicals most likely contribute to plant defence against pests and diseases, and impart a characteristic bitter flavor property to cruciferous vegetables.

collection of foods that share similar nutritional properties or biological classifications

mammalian protein found in Homo sapiens

aspect of the homeostasis of organisms

group of compounds

soup of barley, dried peas, potatoes, and beer

Nutraceutical is a term that evolved scientifically and also through marketing which is used to imply a pharmaceutical effect from plant extracts, compounds, food products which have efficacy and therapeutic influence on clinical outcomes and patient care largely through supplements.

thumb|right|250px|Chemical structure of flavan-3-ol

A ubiquinol is an electron-rich (reduced) form of coenzyme Q (ubiquinone). The term most often refers to ubiquinol-10, with a 10-unit tail most commonly found in humans

Nutritionism is a paradigm that assumes that it is the scientifically identified nutrients in foods that determine the value of individual food stuffs in the diet. In other words, it is the idea that the nutritional value of a food is the sum of all its individual nutrients, vitamins, and other components. Another aspect of the term is the implication that the only point of eating is to promote bodily health. The term is largely pejorative, implying that this way of viewing food is simplistic and harmful, and the term is usually used to label others' views. The greatest popularizer of the term

fat or fatty acid having more than one double or triple bond within the carbon chain

thumb|right|200px|The generic garden peony Peonidin is an O-methylated anthocyanidin derived from Cyanidin, and a primary plant pigment. Peonidin gives purplish-red hues to flowers such as the peony, from which it takes its name, and roses. It is also present in some blue flowers, such as the morning glory.

nutrient intake, and dietary planning that is undertaken before, during and after pregnancy

L-α-Glycerophosphorylcholine (alpha-GPC, choline alfoscerate, '''sn-glycero-3-phosphocholine''') is a natural choline compound found in the brain. It is also a parasympathomimetic acetylcholine precursor which has been investigated for its potential for the treatment of Alzheimer's disease and other dementias.

former method of characterizing antioxidants

any fatty acid having only one double or triple bond within the carbon chain

Sinalbin is a glucosinolate found in the seeds of white mustard, Sinapis alba, and in many wild plant species. In contrast to mustard from black mustard (Brassica nigra) seeds which contain sinigrin, mustard from white mustard seeds has only a weakly pungent taste.

thumb|White cauliflower has anthoxanthin pigments Anthoxanthins () are a type of flavonoid pigments in plants. Anthoxanthins are water-soluble pigments which range in color from a white or colorless to a creamy to a yellow, often on petals of flowers. These pigments are generally whiter in an acid medium and yellowed in an alkaline medium. They are very susceptible to color changes with minerals and metal ions, similar to anthocyanins. Some examples of anthoxanthins include: apigeniun, luteolin, kaempferol, quercetin.

chemical compound

Protein contents of a food

regulation of glucose