We sought to examine the effects of daily consumption of macadamia nuts on body weight and composition, plasma lipids and glycaemic parameters in a free-living environment in overweight and obese adults at elevated cardiometabolic risk. Utilising a randomised cross-over design, thirty-five adults with abdominal obesity consumed their usual diet plus macadamia nuts (~15 % of daily calories) for 8 weeks (intervention) and their usual diet without nuts for 8 weeks (control), with a 2-week washout. Body composition was determined by bioelectrical impedance; dietary intake was assessed with 24-h dietary recalls. Consumption of macadamia nuts led to increased total fat and MUFA intake while SFA intake was unaltered. With mixed model regression analysis, no significant changes in mean weight, BMI, waist circumference, percent body fat or glycaemic parameters, and non-significant reductions in plasma total cholesterol of 2⋅1 % (-4⋅3 mg/dl; 95 % CI -14⋅8, 6⋅1) and low-density lipoprotein (LDL-C) of 4 % (-4⋅7 mg/dl; 95 % CI -14⋅3, 4⋅8) were observed. Cholesterol-lowering effects were modified by adiposity: greater lipid lowering occurred in those with overweight v. obesity, and in those with less than the median percent body fat. Daily consumption of macadamia nuts does not lead to gains in weight or body fat under free-living conditions in overweight or obese adults; non-significant cholesterol lowering occurred without altering saturated fat intake of similar magnitude to cholesterol lowering seen with other nuts. Clinical Trial Registry Number and Website: NCT03801837 https://clinicaltrials.gov/ct2/show/NCT03801837?term = macadamia + nut&draw = 2&rank = 1.
Keywords: % Body fat, percent body fat; Adiposity; Apo A1, apoprotein A1; Apo B, apoprotein B; BFM, body fat mass; Body composition; CV, coefficient of variation; CVD, cardiovascular disease; Cholesterol; DLM, dry lean mass; HOMA2, homeostasis model assessment 2; IR, insulin resistance; LBM, lean body mass; LDL-C; Mac, macadamia nuts; Macadamia nuts; Palmitoleic acid; SMM, skeletal muscle mass; TAG, triacylglycerol; TBW, total body water; TC, total cholesterol; TEE, total energy expenditure; VLDL,, very low-density lipoprotein; WC, waist circumference; oxLDL, oxidised LDL; sdLDL, small dense low-density lipoprotein; se, standard error; sem, standard error of the mean.
© The Author(s) 2023.