Editing Fat (section)

==Dietary sources==
{{Vegetable oils, composition}}

==={{anchor|Saturated fat}}{{anchor|Unsaturated fat}}Saturated vs. unsaturated fats===
<!--merged-from|saturated fat-->
<!--Merged from [[unsaturated fat]]-->

Different foods contain different amounts of fat with different proportions of saturated and unsaturated fatty acids. Some animal products, like [[beef]] and [[dairy products]] made with whole or reduced fat milk like [[yogurt]], [[ice cream]], [[cheese]] and [[butter]] have mostly saturated fatty acids (and some have significant contents of [[dietary cholesterol]]). Other animal products, like [[pork]], [[poultry]], [[Egg as food|eggs]], and seafood have mostly unsaturated fats. Industrialized [[baked goods]] may use fats with high unsaturated fat contents as well, especially those containing [[partially hydrogenated oil]]s, and [[processed food]]s that are [[deep-fried]] in [[Vegetable oil#Hydrogenation|hydrogenated oil]] are high in saturated fat content.<ref name="aha2014" /><ref name="husp2014" /><ref name="choo2020" />

Plants and fish oil generally contain a higher proportion of unsaturated acids, although there are exceptions such as [[coconut oil]] and [[palm kernel oil]].<ref name="reec2002" /><ref name="choos2015b" /> Foods containing unsaturated fats include [[avocado]], [[nut (fruit)|nuts]], [[olive oil]]s, and [[vegetable oil]]s such as [[canola]].

Many [[scientific studies]] have found that replacing saturated fats with ''cis'' unsaturated fats in the diet reduces risk of [[cardiovascular disease]]s (CVDs),<ref name="hoop2020e" /> [[diabetes]], or death.<ref name="sacks2017" /> These studies prompted many medical organizations and public health departments, including the [[World Health Organization]] (WHO),<ref name="who2015" /><ref name="who0000" /> to officially issue that advice. Some countries with such recommendations include:

* United Kingdom<ref name="htuk0000xd" /><ref name="nhsuk0000xe" /><ref name="nhsuk2018" /><ref name="nhsuk0000v" /><ref name="bhfuk0000w" />
* United States<ref name="sacks2017" /><ref name="htus2015" /><ref name="usda0000r" /><ref name="cdc2004" /><ref name="USDA2005u" />
* India<ref name="india0000xf" /><ref name="india0000" />
* Canada<ref name="choos2018q" />
* Australia<ref name="ausmd2012" />
* Singapore<ref name="sing0000" />
* New Zealand<ref name="newz0000" />
* Hong Kong<ref name="hong0000" />

A 2004 review concluded that "no lower safe limit of specific saturated fatty acid intakes has been identified" and recommended that the influence of varying saturated fatty acid intakes against a background of different individual lifestyles and genetic backgrounds should be the focus in future studies.<ref name="germ2004" />

This advice is often oversimplified by labeling the two kinds of fats as ''bad fats'' and ''good fats'', respectively. However, since the fats and oils in most natural and traditionally processed foods contain both unsaturated and saturated fatty acids,<ref name="stor1996" /> the complete exclusion of saturated fat is unrealistic and possibly unwise. For instance, some foods rich in saturated fat, such as coconut and palm oil, are an important source of cheap dietary calories for a large fraction of the population in developing countries.<ref name="who2003s" />

Concerns were also expressed at a 2010 conference of the [[American Dietetic Association]] that a blanket recommendation to avoid saturated fats could drive people to also reduce the amount of polyunsaturated fats, which may have health benefits, and/or replace fats by refined carbohydrates — which carry a high risk of obesity and heart disease.<ref name="zelm2011" />

For these reasons, the U.S. [[Food and Drug Administration]], for example, recommends to consume less than 10% (7% for high-risk groups) of calories from saturated fat, with 15-30% of total calories from all fat.<ref>{{Cite journal |last=Nutrition |first=Center for Food Safety and Applied |date=2022-03-07 |title=Health Claim Notification for Saturated Fat, Cholesterol, and Trans Fat, and Reduced Risk of Heart Disease |url=https://www.fda.gov/food/food-labeling-nutrition/health-claim-notification-saturated-fat-cholesterol-and-trans-fat-and-reduced-risk-heart-disease |journal=FDA |language=en}}</ref><ref name="who2003s" /> A general 7% limit was recommended also by the [[American Heart Association]] (AHA) in 2006.<ref name="lich2006" /><ref name="smith2004" />

The WHO/FAO report also recommended replacing fats so as to reduce the content of myristic and palmitic acids, specifically.<ref name="who2003s" />

The so-called [[Mediterranean diet]], prevalent in many countries in the [[Mediterranean Sea]] area, includes more total fat than the diet of Northern European countries, but most of it is in the form of unsaturated fatty acids (specifically, monounsaturated and omega-3) from olive oil and fish, vegetables, and certain meats like lamb, while consumption of saturated fat is minimal in comparison.
A 2017 review found evidence that a Mediterranean-style diet could reduce the risk of cardiovascular diseases, overall cancer incidence, neurodegenerative diseases, diabetes, and mortality rate.<ref name="dinu2017" /> A 2018 review showed that a Mediterranean-like diet may improve overall health status, such as reduced risk of non-communicable diseases. It also may reduce the social and economic costs of diet-related illnesses.<ref name="mart2018xh" />

A small number of contemporary reviews have challenged this negative view of saturated fats. For example, an evaluation of evidence from 1966 to 1973 of the observed health impact of replacing dietary [[saturated fat]] with [[linoleic acid]] found that it ''increased'' rates of death from all causes, coronary heart disease, and cardiovascular disease.<ref name="sydn0000" /> These studies have been disputed by many scientists,<ref name="will2017" /> and the consensus in the medical community is that saturated fat and cardiovascular disease are closely related.<ref name="souza2015" /><ref name="rams2013" /><ref name="rams2016" /> Still, these discordant studies fueled debate over the merits of substituting polyunsaturated fats for saturated fats.<ref name="weyl2015" />

====Cardiovascular disease====
{{Main|Saturated fat and cardiovascular disease}}

The effect of saturated fat on cardiovascular disease has been extensively studied.<ref name="hoop2020e" /> The general consensus is that there is evidence of moderate-quality of a strong, consistent, and graded relationship between saturated fat intake, [[blood cholesterol]] levels, and the incidence of cardiovascular disease.<ref name="sacks2017" /><ref name="hoop2020e" /> The relationships are accepted as causal,<ref name="grah2007" /><ref name="laba2011" /> including by many government and medical organizations.<ref name="who2003s" /><ref name="kris2007f" /><ref name="bda0000" /><ref name="sacks2017" /><ref name="wohf2017" /><ref name="nhsuk0000" /><ref name="FDA2009h" /><ref name="efsa2010" />

A 2017 review by the AHA estimated that replacement of saturated fat with polyunsaturated fat in the American diet could reduce the risk of cardiovascular diseases by 30%.<ref name="sacks2017" />

The consumption of saturated fat is generally considered a risk factor for [[dyslipidemia]]—abnormal blood lipid levels, including high total cholesterol, high levels of triglycerides, high levels of [[low-density lipoprotein]] (LDL, "bad" cholesterol) or low levels of [[high-density lipoprotein]] (HDL, "good" cholesterol). These parameters in turn are believed to be risk indicators for some types of cardiovascular disease.<ref name="fphuk0000" /><ref name="who2003k" /><ref name="irhf0000" /><ref name="usda2010m" /><ref name="cann2007" /><ref name="wohf2017" /><ref name="cata2011" /><ref name="aha0000xc" /><ref name="merck0000" /> These effects were observed in children too.<ref name="sanch2008" />

Several [[meta-analysis|meta-analyses]] (reviews and consolidations of multiple previously published experimental studies) have confirmed a significant relationship between saturated fat and high [[serum cholesterol]] levels,<ref name="sacks2017" /><ref name="clarke1997" /> which in turn have been claimed to have a causal relation with increased risk of cardiovascular disease (the so-called [[lipid hypothesis]]).<ref name="buck1999" /><ref name="lewin2007" /> However, high cholesterol may be caused by many factors. Other indicators, such as high LDL/HDL ratio, have proved to be more predictive.<ref name="lewin2007" /> In a study of [[myocardial infarction]] in 52 countries, the [[apolipoprotein B|ApoB]]/[[apolipoprotein A1|ApoA1]] (related to LDL and HDL, respectively) ratio was the strongest predictor of CVD among all risk factors.<ref name="laba2011n" /> There are other pathways involving [[obesity]], [[triglyceride]] levels, [[insulin resistance|insulin sensitivity]], [[endothelium|endothelial function]], and [[thrombogenicity]], among others, that play a role in CVD, although it seems, in the absence of an adverse blood lipid profile, the other known risk factors have only a weak [[atherogenic]] effect.<ref name="laba2011p" /> Different saturated fatty acids have differing effects on various lipid levels.<ref name="thij2005" />

====Cancer====
The evidence for a relation between saturated fat intake and [[cancer]] is significantly weaker, and there does not seem to be a clear medical consensus about it.

* Several reviews of [[Case–control study|case–control studies]] have found that saturated fat intake is associated with increased breast cancer risk.<ref>{{cite journal |vauthors=Dandamudi A, Tommie J, Nommsen-Rivers L, Couch S |date=2018|title=Dietary Patterns and Breast Cancer Risk: A Systematic Review|journal=Anticancer Research|volume=38|issue=6|pages=3209–3222|pmid=29848668|doi=10.21873/anticanres.12586|s2cid=44149964|doi-access=free}}</ref><ref>{{cite journal|vauthors=Xia H, Ma S, Wang S, Sun G |year=2015|title=Meta-Analysis of Saturated Fatty Acid Intake and Breast Cancer Risk|journal=Medicine|volume=94|issue=52|pages=e2391|pmid=26717389|doi=10.1097/MD.0000000000002391|pmc=5291630}}</ref><ref>{{cite journal|vauthors=Brennan SF, Woodside JV, Lunny PM, Cardwell CR, Cantwell MM |year=2017|title=Dietary fat and breast cancer mortality: A systematic review and meta-analysis|journal=Critical Reviews in Food Science and Nutrition|volume=57|issue=10|pages=1999–2008|doi=10.1080/10408398.2012.724481|pmid=25692500 |s2cid=34098509 |url=https://pure.qub.ac.uk/en/publications/dietary-fat-and-breast-cancer-mortality-a-systematic-review-and-metaanalysis(d733bb2c-2e38-494e-bb66-03b38759e0c2).html}}</ref>
* Another review found limited evidence for a positive relationship between consuming animal fat and incidence of [[colorectal cancer]].<ref name="xxxx2009a" />
* Other meta-analyses found evidence for increased risk of [[ovarian cancer]] by high consumption of saturated fat.<ref name="hunch2001" />
* Some studies have indicated that serum [[myristic acid]]<ref name="mann2003" /><ref name="crowe2008" /> and [[palmitic acid]]<ref name="crowe2008" /> and dietary myristic<ref name="kura2008" /> and palmitic<ref name="kura2008" /> saturated fatty acids and serum palmitic combined with [[tocopherol#Alpha-tocopherol|alpha-tocopherol]] supplementation<ref name="mann2003" /> are [[Prostate cancer#Oils and fatty acids|associated with increased risk]] of [[prostate cancer]] in a dose-dependent manner. These associations may, however, reflect differences in intake or metabolism of these fatty acids between the precancer cases and controls, rather than being an actual cause.<ref name="crowe2008" />

====Bones====
Various animal studies have indicated that the intake of saturated fat has a negative effect on the [[osteoporosis|mineral density of bones]]. One study suggested that men may be particularly vulnerable.<ref name="corw2006" />

====Disposition and overall health====

Studies have shown that substituting monounsaturated fatty acids for saturated ones is associated with increased daily physical activity and resting energy expenditure. More physical activity, less anger, and less irritability were associated with a higher-oleic acid diet than one of a [[palmitic acid]] diet.<ref name="kien2013" />

[[File:Fatchart.svg|thumb|right|Amounts of fat types in selected foods]]

==={{anchor|Monounsaturated fat}}{{anchor|Polyunsaturated fat}}Monounsaturated vs. polyunsaturated fat===
<!--Merged from [[monounsaturated fat]] -->
<!--Merged from [p[olyunsaturated fat]]-->

[[File:Fat triglyceride shorthand formula.PNG|thumb|300px|Schematic diagram of a triglyceride with a saturated fatty acid (top), a monounsaturated one (middle) and a polyunsaturated one (bottom).]]

The most common fatty acids in human diet are unsaturated or mono-unsaturated. Monounsaturated fats are found in animal flesh such as red [[meat]], whole milk products, nuts, and high fat fruits such as olives and avocados. Olive oil is about 75% monounsaturated fat.<ref name="abdu2017" /> The high oleic variety [[sunflower oil]] contains at least 70% monounsaturated fat.<ref name="huth2015" /> [[Canola oil]] and [[cashew]]s are both about 58% monounsaturated fat.<ref>{{Cite news |last=Shute |first=Nancy |date=2012-05-02 |title=Lard Is Back In The Larder, But Hold The Health Claims |language=en |work=NPR |url=https://www.npr.org/sections/thesalt/2012/05/02/151868208/lard-is-back-in-the-larder-but-hold-the-health-claims |access-date=2022-06-29}}</ref> [[Tallow]] (beef fat) is about 50% monounsaturated fat,<ref name="nrc1974" /> and [[lard]] is about 40% monounsaturated fat.<ref>{{Cite web |date=2015-04-13 |title=Ask the Expert: Concerns about canola oil |url=https://www.hsph.harvard.edu/nutritionsource/2015/04/13/ask-the-expert-concerns-about-canola-oil/ |access-date=2022-06-29 |website=The Nutrition Source |language=en-us}}</ref> Other sources include [[hazelnut]], [[avocado oil]], [[macadamia nut oil]], [[Grape seed oil|grapeseed oil]], groundnut oil ([[peanut oil]]), [[sesame oil]], [[corn oil]], [[popcorn]], [[whole grain]] [[wheat]], [[cereal]], [[oatmeal]], [[almond oil]], [[hemp oil]], and [[tea-oil camellia]].<ref name="aizp2015" />

Polyunsaturated fatty acids can be found mostly in nuts, seeds, fish, seed oils, and [[oyster]]s.<ref name="osu2014" />

Food sources of polyunsaturated fats include:<ref name="osu2014" /><ref name="usda2011a" />
{| class="wikitable sortable"
|-
! Food source (100g) !! Polyunsaturated fat (g)
|-
| [[Walnuts]] || 47
|-
| [[Canola oil]] || 34
|-
| [[Sunflower seed]]s || 33
|-
| [[Sesame seed]]s || 26
|-
| [[Salvia hispanica|Chia seeds]] || 23.7
|-
| [[Peanut#Dry roasted peanuts|Unsalted peanuts]] || 16
|-
| [[Peanut butter]] || 14.2
|-
| [[Avocado oil]] || 13.5<ref name="self0000" />
|-
| [[Olive oil]] || 11
|-
|[[Safflower oil]]
|12.82<ref name="usda2015b" />
|-
| [[Seaweed]] || 11
|-
| [[Sardines]] || 5
|-
| [[Soybeans]] || 7
|-
| [[Tuna]] || 14
|-
| [[Salmon as food|Wild salmon]] || 17.3
|-
| [[Whole grain]] [[wheat]] || 9.7
|}

==== Insulin resistance and sensitivity ====

MUFAs (especially oleic acid) have been found to lower the incidence of [[insulin resistance]]; PUFAs (especially large amounts of [[arachidonic acid]]) and SFAs (such as [[arachidic acid]]) increased it. These ratios can be indexed in the [[phospholipid]]s of human [[skeletal muscle]] and in other tissues as well. This relationship between dietary fats and insulin resistance is presumed secondary to the relationship between insulin resistance and [[inflammation]], which is partially modulated by dietary fat ratios ([[Omega-3 fatty acids|omega−3]]/[[Omega-6 fatty acids|6]]/[[Omega-9 fatty acids|9]]) with both omega−3 and −9 thought to be anti-inflammatory, and omega−6 pro-inflammatory (as well as by numerous other dietary components, particularly [[Health effects of polyphenols|polyphenols]] and exercise, with both of these anti-inflammatory). Although both pro- and anti-inflammatory types of fat are [[biology|biologically]] necessary, fat dietary ratios in most US diets are skewed towards omega−6, with subsequent disinhibition of inflammation and potentiation of insulin resistance.<ref name="stor1996" /> This is contrary to the suggestion that polyunsaturated fats are shown to be protective against insulin resistance.{{cn|date=January 2023}}

The large scale KANWU study found that increasing MUFA and decreasing SFA intake could improve insulin sensitivity, but only when the overall fat intake of the diet was low.<ref name="vess2001" /> However, some MUFAs may promote [[insulin resistance]] (like the SFAs), whereas PUFAs may protect against it.<ref name="love2002" /><ref name="fuku2004" />{{clarify|date=August 2020}}

====Cancer====
Levels of oleic acid along with other MUFAs in red blood cell membranes were positively associated with breast cancer risk. The [[saturation index]] (SI) of the same membranes was inversely associated with breast cancer risk. MUFAs and low SI in erythrocyte membranes are predictors of postmenopausal breast cancer. Both of these variables depend on the activity of the enzyme [[delta-9 desaturase]] (Δ9-d).<ref name="pala2001" />

Results from [[observational study|observational clinical trials]] on PUFA intake and cancer have been inconsistent and vary by numerous factors of cancer incidence, including gender and genetic risk.<ref name="nihw2016" /> Some studies have shown associations between higher intakes and/or blood levels of omega-3 PUFAs and a decreased risk of certain cancers, including breast and colorectal cancer, while other studies found no associations with cancer risk.<ref name="nihw2016" /><ref name="patt2011xk" />

====Pregnancy disorders====
Polyunsaturated fat supplementation was found to have no effect on the incidence of pregnancy-related disorders, such as [[hypertension]] or [[preeclampsia]], but may increase the length of [[gestation]] slightly and decreased the incidence of early premature births.<ref name="osu2014" />

Expert panels in the United States and Europe recommend that pregnant and lactating women consume higher amounts of polyunsaturated fats than the general population to enhance the DHA status of the fetus and newborn.<ref name="osu2014" />

==={{anchor|Trans fat}}"Cis fat" vs. "trans fat"===
{{main|Trans fat}}
In nature, unsaturated fatty acids generally have double bonds in [[cis–trans isomerism|''cis'' configuration]] (with the adjacent C–C bonds on the same side) as opposed to ''trans''.<ref name="mart2007" /> Nevertheless, [[Trans fat|''trans'' fatty acids]] (TFAs) occur in small amounts in meat and milk of [[ruminant]]s (such as cattle and sheep),<ref name="kuhnt2011" /><ref>{{cite book|first1=Fred August |last1=Kummerow |first2=Jean M. |last2=Kummerow|title=Cholesterol Won't Kill You, But Trans Fat Could|publisher=Trafford|year=2008|isbn=978-1-4251-3808-0}}</ref> typically 2–5% of total fat.<ref name="tfca2006" /> Natural TFAs, which include [[conjugated linoleic acid]] (CLA) and [[vaccenic acid]], originate in the [[rumen]] of these animals. CLA has two double bonds, one in the ''cis'' configuration and one in ''trans'', which makes it simultaneously a ''cis''- and a ''trans''-fatty acid.<ref name="mejo0000" />

{| class="wikitable"
|+ Trans fat contents in various natural and traditionally processed foods, in g per 100 g<ref name="tarr2006" />
|-
! Food type
! Trans fat content
|-
| butter
|2 to 7 g
|-
| whole milk
|0.07 to 0.1 g
|-
| animal fat
| 0 to 5 g<ref name="tfca2006" />
|-
|ground beef
|1 g
|}
The processing of fats by hydrogenation can convert some unsaturated fats into trans fat]]s.  The presence of trans fats in various processed foods has received much attention. 
[[File:Margaryn 022.jpg | thumb | upright=1.3 | [[Margarine]], a common product that can contain trans fats]]

[[File:Crisco Cookbook 1912.jpg | thumb | Cover of original [[Crisco]] cookbook, 1912. Crisco was made by hydrogenating cottonseed oil. The formula was revised in the 2000s and now has only a small amount of trans fat.]]

===Omega-three and omega-six fatty acids===
{{main|Omega-3 fatty acid|Omega-6 fatty acid}}
The [[Omega-3 fatty acid|ω−3 fatty acids]] have received substantial attention. Among omega-3 fatty acids, neither long-chain nor short-chain forms were consistently associated with breast cancer risk. High levels of [[docosahexaenoic acid]] (DHA), however, the most abundant omega-3 [[polyunsaturated fatty acid]] in erythrocyte ([[red blood cell]]) membranes, were associated with a reduced risk of breast cancer.<ref name="pala2001" /> The DHA obtained through the consumption of polyunsaturated fatty acids is positively associated with cognitive and behavioral performance.<ref name="rest2008" /> In addition, DHA is vital for the [[grey matter]] structure of the human brain, as well as retinal stimulation and [[neurotransmission]].<ref name="osu2014" />

===Interesterification===
Some studies have investigated the health effects of interesterified (IE) fats, by comparing diets with IE and non-IE fats with the same overall fatty acid composition.<ref name=Alfieri>{{cite journal |display-authors=etal|last1=Andreina Alfieri |title=Effects of Plant Oil Interesterified Triacylglycerols on Lipemia and Human Health |journal=Int J Mol Sci |date=Dec 2017 |volume=19 |issue=1 |page=104 |doi=10.3390/ijms19010104 |doi-access=free |pmid=29301208 |pmc=5796054 }}</ref><ref name="mens2016" />

Several experimental studies in humans found no statistical difference on fasting blood lipids between a diet with large amounts of IE fat, having 25-40% C16:0 or C18:0 on the 2-position, and a similar diet with non-IE fat, having only 3-9% C16:0 or C18:0 on the 2-position.<ref name="zock1995" /><ref name="nest1995" /><ref name="meij1997" /> A negative result was obtained also in a study that compared the effects on blood [[cholesterol]] levels of an IE fat product mimicking [[cocoa butter]] and the real non-IE product.<ref name="gran1970" /><ref name="berry2007a" /><ref name="zamp1994" /><ref name="ylij2001" /><ref name="berry2007b" /><ref name="summ1999" /><ref name="chris2000b" /> Another study found tentative evidence that interesterified fat may lower cardiovascular disease risk.<ref name=Alfieri/>

A 2007 study funded by the Malaysian Palm Oil Board<ref name="sund2007" /> claimed that replacing natural [[palm oil]] by other interesterified or partially hydrogenated fats caused adverse health effects, such as higher [[low-density lipoprotein|LDL]]/[[high-density lipoprotein|HDL]] ratio and [[Blood sugar level|plasma glucose levels]]. However, these effects could be attributed to the higher percentage of saturated acids in the IE and partially hydrogenated fats, rather than to the IE process itself.<ref name="dest2007" /><ref name="mens2003" />

===Rancification===
{{main|Rancidification}}
Unsaturated fats undergo [[auto-oxidation]], which involves replacement of a C-H bond with C-OH unit. The process requires oxygen (air) and is accelerated by the presence of traces of metals, which serve as catalysts. Doubly unsaturated fatty acids are particularly prone to this reaction.  Vegetable oils resist this process to a small degree because they contain antioxidants, such as [[tocopherol]]. Fats and oils often are treated with [[chelation|chelating agents]] such as [[citric acid]] to remove the metal catalysts.
===Role in disease===
{{Main|Hypertriglyceridemia}}
In the human body, high levels of triglycerides in the bloodstream have been linked to [[atherosclerosis]], [[Coronary heart disease|heart disease]]<ref>{{cite news | title=Boston scientists say triglycerides play key role in heart health | newspaper=The Boston Globe | url=https://www.bostonglobe.com/news/science/2014/06/18/boston-researchers-find-that-triglycerides-play-pivotal-role-heart-health/ynrM4QQwIq1fCCoRwMfOAN/story.html |access-date=2014-06-18}}</ref>
and [[stroke]].<ref name="drummond" /> However, the relative negative impact of raised levels of triglycerides compared to that of LDL:HDL ratios is as yet unknown. The risk can be partly accounted for by a strong inverse relationship between triglyceride level and HDL-cholesterol level. But the risk is also due to high triglyceride levels increasing the quantity of [[Low-density lipoprotein#LDL size patterns|small, dense LDL particles]].<ref>{{cite journal |vauthors=Ivanova EA, Myasoedova VA, Melnichenko AA, Grechko AV, Orekhov AN |title=Small Dense Low-Density Lipoprotein as Biomarker for Atherosclerotic Diseases |journal= Oxidative Medicine and Cellular Longevity |volume=2017 |page=1273042 |year=2017 |doi=10.1155/2017/1273042 |pmc= 5441126 |pmid = 28572872 |doi-access=free}}</ref>

=== Guidelines ===
<div class="noprint">[[File:Blood values sorted by mass and molar concentration.png|thumb|450px|[[Reference ranges for blood tests]], showing usual ranges for triglycerides (increasing with age) in orange at right.]]</div>

The [[National Cholesterol Education Program]] has set guidelines for triglyceride levels:<ref>{{cite web |url=https://www.nlm.nih.gov/medlineplus/ency/article/003493.htm |title=Triglycerides |website=MedlinePlus |access-date=2015-04-23 |archive-url=https://web.archive.org/web/20140228062757/http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/Triglycerides_UCM_306029_Article.jsp |archive-date=28 February 2014}}</ref><ref>Crawford, H., Micheal. ''Current Diagnosis & Treatment Cardiology''. 3rd ed. McGraw-Hill Medical, 2009. p19</ref>

{| class="wikitable"
|-
! colspan=2 | Level
! rowspan=2 | Interpretation
|-
! ([[Milligram|mg]]/[[Decilitre|dL]])
! ([[Mole (unit)|mmol]]/[[Litre|L]])
|-
| < 150
| < 1.70
| Normal range – low risk
|-
| 150–199
| 1.70–2.25
| Slightly above normal
|-
| 200–499
| 2.26–5.65
| Some risk
|-
| 500 or higher
| > 5.65
| Very high – high risk
|}
These levels are tested after [[fasting#Medical application|fasting]] 8 to 12 hours. Triglyceride levels remain temporarily higher for a period after eating.

The AHA recommends an optimal triglyceride level of 100{{nbs}}mg/dL (1.1{{nbs}}mmol/L) or lower to improve heart health.<ref>{{cite web|title=What's considered normal?|url=http://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/triglycerides/art-20048186|website=Triglycerides: Why do they matter?|publisher=[[Mayo Clinic]]|date=28 September 2012}}</ref>

=== Reducing triglyceride levels ===
{{Excerpt|Hypertriglyceridemia|Treatment}}