A new study from the Lebanon suggests that vitamin B6 supplementation of male patients with hypertriglyceridemia may reduce plasma concentrations of total cholesterol and HDL cholesterol.
In the randomized controlled trial, 85 male patients around 50 years of age suffering from high blood triglyceride concentrations (above 150 mg/dL) were given supplements of lysine (1 g/d), vitamin B6
(50 mg/d), lysine (1 g/d) plus vitamin B6 (50 mg/d), carnitine (1 g/d), or placebo for 12 weeks (1). The
lipid profile (triglycerides, total cholesterol, LDL and HDL cholesterol) and fasting plasma glucose levels of participants were assessed at the beginning of the study and at six and 12 weeks. The study results showed that vitamin B6 supplementation was associated with a significant reduction in total cholesterol and HDL cholesterol of about 10%. In addition, plasma triglyceride concentration was reduced by 36.6 mg/dL at six weeks, whereas levels in the placebo group increased by 18 mg/dL; this difference failed to reach statistical significance. No major changes in the lipid profile were observed in the lysine and carnitine groups or when lysine was added to vitamin B6.
The researchers commented that in Lebanon a high prevalence of hypertriglyceridemia (52.4% in men) is associated with a high percentage of energy intake from carbohydrates, in which cereal and cereal products are the main component. These products are mainly consumed by individuals of low to moderate socioeco-nomic status. In addition, premenopausal Lebanese women of low to moderate socioeconomic status repor-tedly have low vitamin B6 levels and high plasma triglyceride levels.
The elevation of triglycerides can be the result of primary (various genetic defects) or secondary causes, such as obesity, diabetes, excessive alcohol use, high carbohydrate intake, and use of certain medications. Secondary hypertriglyceridemia is associated with alterations in lipid metabolism related to abnormalities in the transport, synthesis, or oxidative capacity of fatty acids. Carnitine is required for mitochondrial oxidation of long-chain fatty acids. Its synthesis in the body depends on two essential amino acids (lysine and methio-nine) and vitamin B6 or it is obtained from the diet (predominantly from meat and dairy products). Vitamin B6 is needed for carnitine synthesis, which implies that low vitamin B6 levels can impair carnitine synthesis and hence alter the lipid profile.