Three dietary fat sources show similar impact on liver fat concentration

Palm olein, cocoa butter, and soybean oil demonstrated comparable effects on liver fat concentration and amounts of adipose tissue in healthy adults when consumed as part of eucaloric typical Australian diets, according to a study. Moreover, the effects on serum lipids are inconsistent across lipid profiles.

Eighty-three healthy adults (aged 20–45 years; body mass index, 18.5–27.5 kg/m²) were included, of whom 64 completed a 16-week randomized parallel intervention, preceded by a 2-week run-in.

Participants consumed identical eucaloric background diets differing in test fats (contributing 20-percent total energy intake [%E]), providing 33 %E total fat with the following ratios for polyunsaturated fatty acids/saturated fatty acids/monounsaturated fatty acids: palm olein (4.2/13.5/15 %E), soybean oil (14.4/8.8/9.4 %E), and cocoa butter (2.3/19.5/11 %E).

The authors measured liver fat and abdominal adiposity at weeks 0 and 16 using ¹H-magnetic resonance spectroscopy/imaging; all other outcomes were measured at 0, 4, 8, 12, and 16 weeks.

Fat quality had no impact on liver fat concentration, visceral adipose tissue, abdominal subcutaneous adipose tissue, obesity indexes, blood pressure, liver enzymes, leptin, or fasting glucose.

Body fat mass decreased with cocoa butter and soybean oil relative to palm olein. Soybean oil, compared with palm olein, reduced serum total cholesterol (TC), low-density lipoprotein cholesterol, and TC:high-density lipoprotein (HDL) cholesterol (estimated marginal mean differences, –0.57 mmol/L, 95 percent confidence interval [CI], –0.94 to –0.20; –0.37 mmol/L, 95 percent CI, –0.68 to –0.07; and –0.42 mmol/L, 95 percent CI, –0.73 to –0.11, respectively).

There were no differences seen on HDL cholesterol, triacylglycerol, apoA1, apoB, apoB:apoA1, or faecal free fatty acids (FFAs), but cocoa butter led to lower FFA pentadecanoic acid (15:0) compared to palm olein and soybean oil.

“The findings must be confirmed in metabolically impaired individuals before recommendations can be made,” the authors said.