The effect of exercise and diet on Lipoprotein(a) - clinical studies.
To assess the effects of dietary modifications on oxidized low-density lipoprotein (LDL).
Thirty-seven healthy women were fed two diets. Both diets contained a reduced amount of total and saturated fat. In addition, one diet was low in vegetables and the other was high in vegetables, berries, and fruit. The dietary intake of total fat was 70 g per day at baseline and decreased to 56 g (low-fat, low-vegetable diet) and to 59 g (low-fat, high-vegetable diet). The saturated fat intake decreased from 28 g to 20 g and to 19 g, and the amount of polyunsaturated fat intake increased from 11 g to 13 g and to 19 g (baseline; low-fat, low-vegetable; low-fat, high-vegetable; respectively). The amount of oxidized LDL in plasma was determined as the content of oxidized phospholipid per ApoB-100 using a monoclonal antibody EO6 (OxLDL-EO6). The median plasma OxLDL-EO6 increased by 27% (P<0.01) in response to the low-fat, low-vegetable diet and 19% (P<0.01) in response to the low-fat, high-vegetable diet. Also, the Lp(a) concentration was increased by 7% (P<0.01) and 9% (P=0.01), respectively.
Alterations in the dietary fat intake resulted in increased plasma concentrations of lipoprotein(a) and OxLDL-EO6.
Changes in lipoprotein(a), oxidized phospholipids, and LDL subclasses with a low-fat high-carbohydrate diet
Nastaran Faghihnia, Sotirios Tsimikas, [...], and Ronald M. Krauss
Low-fat diets have been shown to increase plasma concentrations of lipoprotein(a) [Lp(a)], a preferential lipoprotein carrier of oxidized phospholipids (OxPLs) in plasma, as well as small dense LDL particles. We sought to determine whether increases in plasma Lp(a) induced by a low-fat high-carbohydrate (LFHC) diet are related to changes in OxPL and LDL subclasses. We studied 63 healthy subjects after 4 weeks of consuming, in random order, a high-fat low-carbohydrate (HFLC) diet and a LFHC diet. Plasma concentrations of Lp(a) (P < 0.01), OxPL/apolipoprotein (apo)B (P < 0.005), and OxPL-apo(a) (P < 0.05) were significantly higher on the LFHC diet compared with the HFLC diet whereas LDL peak particle size was significantly smaller (P < 0.0001). Diet-induced changes in Lp(a) were strongly correlated with changes in OxPL/apoB (P < 0.0001). The increases in plasma Lp(a) levels after the LFHC diet were also correlated with decreases in medium LDL particles (P < 0.01) and increases in very small LDL particles (P < 0.05). These results demonstrate that induction of increased levels of Lp(a) by an LFHC diet is associated with increases in OxPLs and with changes in LDL subclass distribution that may reflect altered metabolism of Lp(a) particles.
Effects of physical activity and diet on lipoprotein(a).
Mackinnon LT, Hubinger L, Lepre F.
Department of Human Movement Studies and Medicine, University of Queensland, Brisbane, Australia. email@example.com
Lipoprotein(a) [Lp(a)] represents a class of lipoproteins with some structural similarity to low density lipoprotein (LDL), but containing a unique apoprotein, apoprotein(a). First reported in 1963, Lp(a) is now considered to have an independent role in the development of atherosclerotic lesions. The level of Lp(a) in the blood is under strong genetic influence and does not appear to be alterable by lifestyle factors known to influence other lipoproteins. Regular moderate exercise has been shown to favorably alter other lipoproteins, and recent attention has focused on whether Lp(a) level can be influenced by physical activity. Current data from cross-sectional and intervention studies show little effect of moderate exercise on serum Lp(a) concentration. One possible exception may be an elevation of serum Lp(a) concentration in adult endurance and power athletes who exercise intensely on a daily basis. However, not all studies have taken into account possible racial or ethnic differences in Lp(a) concentrations and the skewed distribution observed within most populations. Standard dietary intervention such as a low fat diet recommended for weight loss and control of other blood lipids has little effect on serum Lp(a) level. At present, serum Lp(a) concentration does not appear to be significantly altered by realistic dietary changes and moderate physical activity as recommended for health. The synergistic effect on cardiovascular disease risk when both LDL-cholesterol and Lp(a) are elevated highlight the importance of attending to those risk factors that can be modified by exercise and other lifestyle changes.