The mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism is reportedly associated with longevity in the Japanese population, and the Mt5178A genotype may exert anti-atherogenic effects. The aim of this study was to determine whether there were longitudinal differences in serum lipid levels between carriers of the Mt5178C genotype and those of the Mt5178A genotype and to assess the impact of these genotypes on serum cholesterol levels.

The serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), and low-density lipoprotein cholesterol (LDLC) were measured and the Mt5178 C/A genotypes determined in 110 Japanese men aged 41–66 (mean 52.3) years who had received medical checkups twice in the period 1999–2005. The longitudinal changes of TC, HDLC, and LDLC were calculated according to genotype.

The serum levels of TC at baseline and follow-up were significantly different, whereas those of HDLC and LDLC were not. The changes in HDLC differed significantly between the two Mt5178 C/A genotype groups, with the changes in HDLC level being significantly greater in the Mt5178A genotype group than in the Mt5178C group ( p = 0.015).

The Mt5178 C/A genotype may modify longitudinal changes in serum TC and HDLC levels in middle-aged Japanese men.