Impact of myristic acid versus palmitic acid on serum lipid and lipoprotein levels in healthy women and men.

Abstract

The cholesterol-raising effect of dietary saturated fatty acids is largely accounted for by lauric, myristic, and palmitic acids. Dairy fat is a major source of myristic acid, and palm oil is especially rich in palmitic acid. Myristic acid is suspected of being much more cholesterolemic than palmitic acid, but direct comparisons have been lacking. We therefore fed 36 women and 23 men three diets that differed from each other in palmitic, oleic, and myristic acid content by about 10% of total energy. We used palm oil, high-oleic acid sunflower oil, and a specially produced high-myristic acid fat to achieve these differences. Each diet was consumed for 3 weeks in random order. Mean serum cholesterol was 4.53 mmol/L on the high-oleic acid diet, 4.96 mmol/L on the palmitic acid diet, and 5.19 mmol/L on the myristic acid diet (/'<.0001 for all comparisons). Myristic acid raised low-density upoprotein (LDL) cholesterol by 0.11 mmol/L, high-density R educing saturated fat (and cholesterol) intake is the therapy of choice in the treatment of moderate hypercholesterolemia and an important adjunct to drug therapy in the treatment of severe hypercholesterolemia.1 Restriction of saturated fatty acids in the diet is more effective than limiting total fat consumption.2 However, saturates with different chain lengths may differ in their cholesterol-raising effect. Lauric acid (C12:0), myristic acid (C14:0), and palmitic acid (C16:0) are thought to increase cholesterol levels, whereas stearic acid (C18:0) has little or no effect.3 7 In experimental animals, saturated fatty acids raise plasma cholesterol through downregulation of low-density lipoprotein (LDL) receptor activity and subsequent accumulation of LDL cholesterol (LDL-C) in plasma and increased LDL production from its precursor, very-lowdensity lipoprotein (VLDL). 8 -9 These effects are seen with lauric, myristic, and palmitic acids but not with medium-chain saturates (C6:0, C8:0, and C10:0) or stearic acid. 10 In humans lauric acid is less potent than palmitic acid in raising total cholesterol and LDL-(34,11,12 Myristic acid and palmitic acid together make up about 25% to 30% of the fat in Western diets (D. Kromhout, unpublished data, 1988), but their relative cholesterol-raising potencies have not been clearly defined in humans. Meta-analyses of dietary trials that employed commercially available fats indicate that myristic acid might be four to six times more cholesterReceived October 29, 1993; revision accepted January 3, 1994. From the Department of Human Nutrition, Wageningen Agricultural University, Wageningen, the Netherlands.Correspondence to Prof Dr M.B. Katan, Department of Human Nutrition, Wageningen Agricultural University, Bomenweg 2, 6703 HD Wageningen, the Netherlands. lipoprotein (HDL) cholesterol by 0.12 mmol/L, and apolipoprotein (apo) A-I by 7.2 mg/dL relative to palmitic acid; increases relative to oleic acid were 0.50 mmol/L for LDL cholesterol, 0.15 mmol/L for HDL cholesterol, 6.0 mg/dL for apoB, and 8.9 mg/dL for apoA-I (P<.01 for all c...

Seasonal variation in fatty acid composition in various parts of broccoli cultivars

“…acids (Denkeand Grundy, 1992;Zock et al, 1994) raise cholesterol levels, which is a major risk factor in CHD (Grundy, 1997), high compositional ratio of these fatty acids in food is not suitable for health. So, to overcome from this situation, development of cultivar having lower ratio of saturated fatty acid (higher UFA ratio), will be good for the human diet.…”

Effect of synthetic triglycerides of myristic, palmitic, and stearic acid on serum lipoprotein metabolism

“…Multiple regression analysis of data from investigations of natural fats and oils suggested 14:0 is the most cholesterolemic saturated fatty acid (Hegsted et al, 1965;Mensink & Katan, 1992), but, despite the statistical associations, myristic acid (14:0) is not the major saturated fatty acid in any commonly consumed natural products including butter, meat, and tropical oils (USDA, 1979), and diets high in myristic acid are even higher in lauric or palmitic acid. Previous research involving the feeding of a synthetic 14:0 diet indicated that mean LDL-C concentration on 14:0 and 16:0 (fed in synthetic form) were not different (Tholstrup et al, 1994a) or that mean LDL-C was about 4% or 0.11 mmolaL higher (P`0.0086) on 14:0 than on 16:0 fed as palm oil (Zock et al, 1994). In this study myristic acid seemed less cholesterolemic in contrast to palmitic acid than in many previous studies.…”

“…One must feed a synthetic triglyceride to obtain a diet in which myristate is the major saturated fatty acid. Results of human feeding studies involving a high myristic or palmitic acid synthetic fat suggested that myristic acid either was not more cholesterolemic than palmitic acid (Tholstrup et al, 1994a) or produced, on average, about 4% higher levels of LDL-C (Zock et al, 1994). A synthetic high lauric acid oil raised plasma LDL cholesterol concentrations less than did a natural source of palmitic acid (Denke & Grundy, 1992).…”

The Fatty Acid and Sterol Content of Food Composites of Middle-Aged Men in Seven Countries

“…Weighed food records give an average underestimation of energy intake of some 10% (de Vries et al, 1994), but they still remain the most accurate method of dietary assessment (Bingham et al, 1995). Body mass index, age, and gender appear to be the major factors associated with underreporting (Black et al, 1993;Jörgensen, 1992;Schoeller et al, 1990), although some studies did not find an effect of obesity Lissner et al, 1989).…”

“…We found small differences in medium-chain fatty acid intake between cohorts, but stearic acid was 10 times higher in Finland and Slavonia than in Japan (Table 4). Palmitic (C16:0), myristic (C14:0), and lauric (C12:0) acid clearly raise LDL cholesterol, and therefore are considered atherogenic (Willett and Sacks, 1991;Grundy, 1990;Zock et al, 1994). Finland had the highest intakes of all three of these fatty acids, due to a high intake of butter and milk, and Tanushimaru, Japan, had the lowest.…”