Saturated fat

Saturated fat is fat that consists of triglycerides containing only saturated fatty acid radicals. There are several kinds of naturally occurring saturated fatty acids, which differ by the number of carbon atoms, ranging from 3 carbons (propionic acid) to 36 (Hexatriacontanoic acid). Saturated fatty acids have no double bonds between the carbon atoms of the fatty acid chain and are thus fully saturated with hydrogen atoms.

Fat that occurs naturally in tissue contains varying proportions of saturated and unsaturated fat. Examples of foods containing a high proportion of saturated fat include dairy products (especially cream and cheese but also butter and ghee); animal fats such as suet, tallow, lard and fatty meat; coconut oil, cottonseed oil, palm kernel oil, chocolate, and some prepared foods.^[1]

Serum saturated fatty acid is generally higher in smokers, alcohol drinkers and obese people.^[2]

Fat profiles

While nutrition labels usually combine them, the saturated fatty acids appear in different proportions among food groups. Lauric and myristic acid radicals are most commonly found in "tropical" oils (e.g. palm kernel, coconut) and dairy products. The saturated fat in meat, eggs, chocolate, and nuts is primarily the triglycerides of palmitic and stearic acid.

Fat composition in different foods (click at right to hide or show)

Food	Saturated	Monounsaturated	Polyunsaturated
	As weight percent (%) of total fat
Cooking oils
Canola oil	7	59	29
Corn oil	13	24	59
Olive oil	13	74	8
Sunflower oil	10.3[4]	19.5[4]	65.7[4]
Soybean oil	15	24	58
Coconut oil	92	6	2
Dairy Products
Cheese,regular	64	29	3
Cheese,light	60	30	0
Milk, whole	62	28	4
Milk, 2%	62	30	0
Ice cream, gourmet	62	29	4
Ice cream, light	62	29	4
Meats
Beef	33	38	5
Ground sirloin	38	44	4
Pork chop	35	44	8
Ham	35	49	16
Chicken breast	29	34	21
Chicken	34	23	30
Turkey breast	30	20	30
Turkey drumstick	32	22	30
Fish,orange roughy	23	15	46
Salmon	28	33	28
Hot dog, beef	42	48	5
Hot dog, turkey	28	40	22
Burger, fast food	36	44	6
Cheeseburger, fast food	43	40	7
Breaded chicken sandwich	20	39	32
Grilled chicken sandwich	26	42	20
Sausage, Polish	37	46	11
Sausage, turkey	28	40	22
Pizza, sausage	41	32	20
Pizza, cheese	60	28	5
Nuts
Almonds dry roasted	9	65	1
Cashews dry roasted	20	59	17
Macadamia dry roasted	15	79	2
Peanuts dry roasted	14	50	31
Pecans dry roasted	8	62	25
Flaxseeds, ground	8	23	65
Sesame seeds	14	38	44
Soybeans	14	22	57
Sunflower seeds	11	19	66
Walnuts dry roasted	9	23	63
Sweets and baked goods
Candy, chocolate bar	59	33	3
Candy, fruit chews	14	44	38
Cookie, oatmeal raisin	22	47	27
Cookie, chocolate chip	35	42	18
Cake, yellow	60	25	10
Pastry, Danish	50	31	14
Fats added during cooking or at the table
Butter, stick	63	29	3
Butter, whipped	62	29	4
Margarine, stick	18	39	39
Margarine, tub	16	33	49
Margarine, light tub	19	46	33
Lard	39	45	11
Shortening	25	45	26
Chicken fat	30	45	21
Beef fat	41	43	3
Dressing, blue cheese	16	54	25
Dressing, light Italian	14	24	58
Other
Egg yolk fat	36[5]	44[5]	16[5]
Unless else specified in boxes, then reference is: [6]

Examples of saturated fatty acids

Some common examples of fatty acids:

• Butyric acid with 4 carbon atoms (contained in butter)
• Lauric acid with 12 carbon atoms (contained in coconut oil, palm oil, and breast milk)
• Myristic acid with 14 carbon atoms (contained in cow's milk and dairy products)
• Palmitic acid with 16 carbon atoms (contained in palm oil and meat)
• Stearic acid with 18 carbon atoms (also contained in meat and cocoa butter)

Stable deepfry and baking medium

Deepfry oils and baking fats that are high in saturated fats, like palm oil, tallow or lard, can withstand extreme heat (of 180-200 degrees Celsius) and are resistant to oxidation. A 2001 parallel review of 20-year dietary fat studies in the United Kingdom, the United States of America and Spain concluded that polyunsaturated oils like soya, canola, sunflower and corn degrade easily to toxic compounds and trans fat when heated up. Prolonged consumption of trans fat-laden oxidized oils can lead to atherosclerosis, inflammatory joint disease and development of birth defects. The scientists also questioned global health authorities’ wilful recommendation of large amounts of polyunsaturated fats into the human diet without accompanying measures to ensure the protection of these fatty acids against heat- and oxidative-degradation.^[7]

Association with diseases

Cardiovascular diseases

In 2010, a meta-analysis of prospective cohort studies including 348,000 subjects found no statistically significant relationship between cardiovascular disease and dietary saturated fat.^[8][9] However, the authors noted that randomized controlled clinical trials in which saturated fat was replaced with polyunsaturated fat observed a reduction in heart disease, and that the ratio between polyunsaturated fat and saturated fat may be a key factor.^[8] In 2009, a systematic review of prospective cohort studies or randomized trials concluded that there was "insufficient evidence of association" between intake of saturated fatty acids and coronary heart disease, and pointed to strong evidence for protective factors such as vegetables and a Mediterranean diet and harmful factors such as trans fats and foods with a high glycemic index.^[10]

An evaluation of data from Harvard Nurses' Health Study found that "diets lower in carbohydrate and higher in protein and fat are not associated with increased risk of coronary heart disease in women. When vegetable sources of fat and protein are chosen, these diets may moderately reduce the risk of coronary heart disease."^[11]

Mayo Clinic highlighted oils that are high in saturated fats include coconut, palm oil and palm kernel oil. Those of lower amounts of saturated fats, and higher levels of unsaturated (preferably monounsaturated) fats like olive oil, peanut oil, canola oil, avocados, safflower, corn, sunflower, soy and cottonseed oils are generally healthier.^[12] However, high intake of saturated dairy fat does not appear to increase the risk of cardiovascular disease^[13] and Pacific island populations who obtain 30-60% of their total caloric intake from fully saturated coconut fat have almost non-existent rates of cardiovascular disease.^[14]

Cancer

Breast cancer

A study published in 2001 found higher levels of monounsaturated fatty acids (especially oleic acid) in the erythrocyte membranes of postmenopausal women who developed breast cancer.^[15] However, another study showed a direct relation between very high consumption of omega-6 polyunsaturated fats and breast cancer in postmenopausal women.^[16]

Prostate cancer

Some researchers have indicated that serum myristic acid^[17][18] and palmitic acid^[18] and dietary myristic^[19] and palmitic^[19] saturated fatty acids and serum palmitic combined with alpha-tocopherol supplementation^[17] are 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.^[18]

Small intestine cancer

A prospective study of data from the NIH-AARP Diet and Health Study correlated saturated fat intake with cancer of the small intestine.^[20]

Dietary recommendations

A 2004 statement released by the Centers for Disease Control (CDC) determined that "Americans need to continue working to reduce saturated fat intake…"^[21] Additionally, reviews by the American Heart Association led the Association to recommend reducing saturated fat intake to less than 7% of total calories according to its 2006 recommendations.^[22][23] This concurs with similar conclusions made by the World Health Organization (WHO) and the US Department of Health and Human Services, both of which determined that reduction in saturated fat consumption would positively affect health and reduce the prevalence of heart disease.^[24][25][26]

The World Health Organization (WHO) has concluded that saturated fats negatively affect cholesterol profiles, predisposing individuals to heart disease, and recommends avoiding saturated fats in order to reduce the risk of a cardiovascular disease.^[27][28]

Dr German and Dr Dillard of University of California and Nestle Research Center in Switzerland, in their 2004 review, pointed out that "no lower safe limit of specific saturated fatty acid intakes has been identified". No randomized clinical trials of low-fat diets or low-saturated fat diets of sufficient duration have been carried out. 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.^[29]

Confounding factors

An association between serum levels of fatty acids and disease does not in itself establish causality.^[30][31]

• The formation of exogenous (outside the body) advanced glycation endproducts (AGEs) and oxidation products generated during cooking may be a confounding factor that some studies may not have controlled for. It has been suggested that, "given the prominence of this type of food in the human diet, the deleterious effects of high-(saturated)fat foods may be in part due to the high content in glycotoxins, above and beyond those due to oxidized fatty acid derivatives." The glycotoxins, as he called them, are more commonly called AGEs^[32]
• Studies of dietary customs of certain ethnic groups may be confounded by other cultural customs. For example, Fulani of northern Nigeria get around 25% of energy from saturated fat, yet their lipid profile is indicative of a low risk of cardiovascular disease. However, this finding is likely due to their high activity level and their low total energy intake.^[33]
• Saturated fat intakes may be monitored more closely than were total fat intakes, therefore ignoring the possibility that simply a larger fat intake may lead to a higher risk of coronary diseases. It also suggests that other parameters may be overlooked, such as carbohydrates intakes.^[34]

Molecular description

Two-dimensional representation of the saturated fatty acid myristic acid

A space-filling model of the saturated fatty acid myristic acid

See also

References