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[[Fasciculus:Trimyristin-3D-vdW.png|thumb|Moleculum pinguis, seu triglyceridi, quae ex [[glycerolum|glycerolo]] et tribus [[acidum pingue|acidis pinguibus]] componitur.]]
{{in progressu}}
'''Pingue''' est substantia crassa, unum ex tribus [[macronutrimentum|macronutriemntis]] (cetera sunt [[hydratum carbonii|hydrata carbonii]] et [[proteinum|proteina]]) quae in victu hominum necessaria sunt, et forma principalis qua [[energia]] in corpore humano conservatur. Quod ad [[chemia]]m spectat, pingue est genus [[lipidum|lipidorum]] quod ex [[triglyceridum|triglyceridis]] componitur.
[[Fasciculus:Trimyristin-3D-vdW.png|alt=A space-filling model of an unsaturated triglyceride.|thumb|A fat, or triglyceride, molecule. Note the three fatty acid chains attached to the central glycerol portion of the molecule.]]
[[Fasciculus:Fat_composition_in_foods.png|thumb|Composition of fats from various foods, as percentage of their total fat.]]
== De vocabulo ==
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In lingua Latina classica distinguuntur ''pingue'' 'liquor crassus'; ''adeps'' 'pinguedo liquida sine sensu, quae nequeat facile durari'; ''sebum'' vel ''sevum'' 'oleosa et pinguis substantia, adipe siccior, concretior et magis compacta, fragilior etiam et igne difficilius liquescens'.<ref>{{Forcellini}}</ref>
'''Fat '''is one of the three main macronutrients, along with [[Hydratum carbonii|carbohydrate]] and [[Proteinum|protein]].'''<ref>{{Cite web|url=http://www.mckinley.illinois.edu/handouts/macronutrients.htm|title=Macronutrients: the Importance of Carbohydrate, Protein, and Fat|date=|accessdate=20 September 2014|website=McKinley Health Center|publisher=[[University of Illinois at Urbana-Champaign]]}}</ref>''' Fats, also known as triglycerides, are [[Ester|esters]] of three fatty acid chains and the [[alcohol]] glycerol. The terms "oil", "fat", and "[[Lipidum|lipid]]" are often confused. "Oil" normally refers to a fat with short or [[Alkenum|unsaturated]] fatty acid chains that is liquid at room temperature, while "fat" may specifically refer to fats that are solids at room temperature. "Lipid" is the general term, though a lipid is not necessarily a triglyceride. Fats, like other lipids, are generally hydrophobic, and are soluble in organic solvents and insoluble in water.
Fat is an important foodstuff for many forms of life, and fats serve both structural and metabolic functions. They are a necessary part of the [[Diaeta|diet]] of most heterotrophs (including humans). Some fatty acids that are set free by the digestion of fats are called essential because they cannot be synthesized in the body from simpler constituents. There are two essential fatty acids (EFAs) in human nutrition: alpha-linolenic acid (an [[Omega-3|omega-3 fatty acid]]) and linoleic acid (an omega-6 fatty acid).<ref name=":0">{{Cite journal|last=Mozaffarian|first=Dariush|last2=Katan|first2=Martijn B.|last3=Ascherio|first3=Alberto|last4=Stampfer|first4=Meir J.|last5=Willett|first5=Walter C.|date=2006-04-13|title=Trans Fatty Acids and Cardiovascular Disease|url=http://dx.doi.org/10.1056/NEJMra054035|journal=New England Journal of Medicine|volume=354|issue=15|pages=1601–1613|doi=10.1056/NEJMra054035|issn=0028-4793|pmid=16611951}}</ref> Other lipids needed by the body can be synthesized from these and other fats. Fats and other lipids are broken down in the body by enzymes called lipases produced in the [[pancreas]].
Fats and oils are categorized according to the number and bonding of the carbon atoms in the aliphatic chain. Fats that are saturated fats have no double bonds between the carbons in the chain. Unsaturated fats have one or more double bonded carbons in the chain. The nomenclature is based on the non-acid (non-carbonyl) end of the chain. This end is called the omega end or the n-end. Thus alpha-linolenic acid is called an [[Omega-3|omega-3 fatty acid]] because the 3rd carbon from that end is the first double bonded carbon in the chain counting from that end. Some oils and fats have multiple double bonds and are therefore called polyunsaturated fats. Unsaturated fats can be further divided into cis fats, which are the most common in nature, and trans fats, which are rare in nature. Unsaturated fats can be altered by reaction with hydrogen effected by a catalyst. This action, called hydrogenation, tends to break all the double bonds and makes a fully saturated fat. To make vegetable shortening, then, liquid ''cis''-unsaturated fats such as vegetable oils are hydrogenated to produce saturated fats, which have more desirable physical properties e.g., they melt at a desirable temperature (30–40 °C), and store well, whereas polyunsaturated oils go rancid when they react with oxygen in the air. However, trans fats are generated during hydrogenation as contaminants created by an unwanted side reaction on the catalyst during partial hydrogenation.
Saturated fats can stack themselves in a closely packed arrangement, so they can solidify easily and are typically solid at room temperature. For example, animal fats tallow and lard are high in saturated fatty acid content and are solids. Olive and linseed oils on the other hand are unsaturated and liquid. Fats serve both as energy sources for the body, and as stores for energy in excess of what the body needs immediately. Each gram of fat when burned or metabolized releases about 9 food calories (37 [[Joulium|kJ]] = 8.8 kcal).<ref name="uk">United Kingdom [http://www.legislation.gov.uk/uksi/1996/1499/contents/made The Food Labelling Regulations 1996] – [http://www.legislation.gov.uk/uksi/1996/1499/schedule/7/made Schedule 7: Nutrition labelling]</ref> Fats are broken down in the healthy body to release their constituents, glycerol and fatty acids. Glycerol itself can be converted to [[Glucosum|glucose]] by the liver and so become a source of energy.-->
== Nexus externi ==
* [https://medlineplus.gov/dietaryfats.html De pinguibus victualibus] apud MedlinePlus {{ling|Anglice}}
* [https://www.uptodate.com/contents/dietary-fat?source=search_result&search=fat&selectedTitle=1%7E150 De pinguibus victualibus] apud UpToDate {{ling|Anglice}}
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