Effects of dietary and exercise treatments on HDL subclasses in lactating women with overweight and obesity: a secondary analysis of a randomised controlled trial

Abstract

Childbearing decreases High Density Lipoprotein cholesterol (HDL-C), potentially contributing to the increased risk of cardiovascular disease (CVD) in parous women. Large HDL particles (HDL-P) are associated with lower risk of CVD. In this secondary analysis of a randomised controlled trial, we investigated the effects of 12-week Dietary and Exercise treatments on HDL-P subclass concentration, size and apolipoprotein A1 (apoA1) in lactating women with overweight/obesity. At 10-14 weeks postpartum, 68 women with pre-pregnant BMI 25-35 kg/m2 were randomised to four groups using 2x2 factorial design: 1) Dietary treatment for weight loss 2) Exercise treatment, 3) both treatments and 4) no treatment. Lipoprotein subclass profiling by Nuclear Magnetic Resonance spectroscopy was performed in serum at randomisation and after 3- and 12-months, and the results analysed with two-way ANCOVA. Lipid concentrations decline naturally postpartum. At 3 months (5-6 months postpartum), both Diet (p=0.003) and Exercise (p=0.008) reduced small HDL-P concentration. Concurrently, Exercise limited the decline in very large HDL-P (p=0.002) and the effect was still significant at 12 months (15 months postpartum) (p=0.041). At 12 months, Diet limited the decline in very large HDL-P (p=0.005), large HDL-P (p=0.001) and apoA1 (p=0.002) as well as HDL size (p=0.002). The Dietary treatment for weight loss and the Exercise treatment both showed effects on HDL-P subclasses in lactating women with overweight and obesity possibly associated with lower CVD-risk. The Dietary treatment had more effects than the Exercise treatment at 12 months, likely associated with a 10% weight loss.

Effects of fat loss and low energy availability on the serum cardiometabolic profile of physique athletes

“…Increased particle number, cholesterol and phospholipid concentrations of large HDL particles were correlated with opposite changes in large VLDL particles, possibly due to the reduced dietary intake and/or increased exercise accelerating VLDL particle lipolysis and concomitant lipid transfer to HDL particles. 21,22 A similar link between the metabolism of triglyceride-rich particles and HDL was also proposed in an NMR-spectroscopy study in lactating women, 23 where both diet-and exercise-induced weight loss conditions were found to have favorable effects on the size and phospholipid concentration of HDL particles. Furthermore, our previous study found decreased level of lipoprotein lipase inhibitors in the end of the competitors' fat loss period, 13 suggesting that enhanced VLDL lipolysis could have contributed to the increased HDL lipid concentrations.…”