Saturated fat

Types of fats in food
Unsaturated fat Monounsaturated fat Polyunsaturated fat Trans fat Omega: 3, 6, 9 Saturated fat Interesterified fat
See also
Fatty acid Essential fatty acid

Saturated fat is fat that consists of triglycerides containing only saturated fatty acids.

Explanation

Fat that occurs naturally in living matter contains varying proportions of saturated and unsaturated fat. Foods that contain a high proportion of saturated fat are butter, ghee, suet, tallow, lard, coconut oil, cottonseed oil, and palm kernel oil, dairy products (especially cream and cheese), meat, chocolate, and some prepared foods^[1].

There are several kinds of naturally occurring saturated fatty acids, their only difference being the number of carbon atoms - from 1 to 24. Saturated fatty acids have no double bonds between the carbon atoms of the fatty acid chain; hence, they are fully saturated with hydrogen atoms.

While nutrition labels usually lump them together, the saturated fatty acids appear in different proportions among food groups. Lauric and myristic acids 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 palmitic and stearic acid.

saturated fat profile of common foods (percentage of total fat)^[2]

Food	Lauric acid	Myristic acid	Palmitic acid	Stearic acid
Coconut oil	47%	18%	9%	3%
Butter	3%	11%	29%	13%
Ground beef	0%	4%	26%	15%
Dark chocolate	0%	0%	34%	43%
Salmon	0%	1%	29%	3%
Eggs	0%	0%	27%	10%
Cashews	2%	1%	10%	7%
Soybean oil	0%	0%	11%	4%

Examples of saturated fatty acids

Some common examples of fatty acids are:

• 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 milk and dairy products),
• palmitic acid with 16 carbon atoms (contained in palm oil, hence the name, and meat),
• stearic acid with 18 carbon atoms (also contained in meat and cocoa butter).

Health issues

The relationship between dietary fats and CVD, especially coronary heart disease, has been extensively investigated, with strong and consistent associations emerging from a wide body of evidence accrued from animal experiments, as well as observational studies, clinical trials and metabolic studies conducted in diverse human populations...Saturated fatty acids raise total and low-density lipoprotein (LDL) cholesterol...The most effective replacement for saturated fatty acids in terms of coronary heart disease outcome are polyunsaturated fatty acids, especially linoleic acid. This finding is supported by the results of several large randomized clinical trials, in which replacement of saturated and trans fatty acids by polyunsaturated vegetable oils lowered coronary heart disease risk.

– World Health Organization, Population nutrient intake goals for preventing diet-related chronic diseases,5.4.4

Diets high in saturated fat are correlated with an increased incidence of atherosclerosis and coronary heart disease according to a number of studies, both African green monkeys^[3] and human.^[4][5][6][7] Some studies have suggested that diets high in saturated fat increase the risk of heart disease and stroke. Epidemiological studies have found that those whose diets are high in saturated fatty acids, including lauric, myristic, palmitic, and stearic acid, had a higher prevalence of coronary heart disease.^{[8][9][10][11]} Additionally, controlled experimental studies have found that people consuming high saturated fat diets experience negative cholesterol profile changes.^{[4][12][13][14]} A 2003 meta-analysis published in the American Journal of Clinical Nutrition concluded that diets high in saturated fat negatively affected cholesterol profiles — predictors of a heart attack and other cardiovascular diseases.^[15]

Experiments in which subjects were randomly assigned to either a control or Mediterranean diet (which replaces saturated fat with mono and polyunsaturated fat) showed a significantly decreased likelihood of suffering a second heart attack, cardiac death, heart failure or stroke.^[16][17]

Epidemiological studies of heart disease have implicated the four major saturated fatty acids to varying degrees. The World Health Organization has determined that there is "convincing" evidence that myristic and palmitic acid intake increases the probability, "possible" risk from lauric acid, and no increased risk at all from stearic acid consumption.^[18]

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..." ^[19] 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.^{[20] [21]} 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.^{[22][15] [23]}

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. ^{[24] [25]}

Contrary research

• A 3-year study of 235 women, released in 2004, concluded that "in postmenopausal women with relatively low total fat intake, a greater saturated fat intake is associated with less progression of coronary atherosclerosis.". Coronary angiography was employed to examine 2,243 coronary artery segments; once at the start of the study and once more at its conclusion. The same study revealed similarly surprising results when it was disclosed that a greater consumption of polyunsaturated oils "was also associated with greater progression of atherosclerosis".^{[26] [27]}

• A study of 297 acute MI cases in Portuguese males, published in February of 2007, concluded that, "Total fat intake, lauric acid, palmitic acid, and oleic acid were inversely associated with acute MI" and that, "Low intake of total fat and lauric acid from dairy products was related to acute MI". The researchers also stated, in revealing the results of this study, that "some prospective studies show that replacing saturated fat with unsaturated fat is more effective in lowering CHD risk than reducing total fat consumption".^[28]

• One study of women who suffered from "metabolic syndrome," a combination of medical disorders that increases the risk of developing cardiovascular disease and diabetes, found that those who had regularly consumed the greatest amounts of saturated fats had the least amount of additional atherosclerotic plaque buildup in their arteries. Additionally, women in the study who ate the most saturated fat had a healthier balance of HDL and LDL cholesterol, and more desirable blood serum concentrations of triglycerides and free fatty acids.

• 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. This finding is likely due to their high activity level and their low total energy intake.^[29]

Molecular description

See also

References