Genetics
Cutting dietary saturated fat raises Lp(a) by 24% in African Americans, more so with smaller apo(a) isoforms (Nutrients 2025)
Original title: Lipoprotein(a) Response to Dietary Saturated Fat Reduction: Relationship to Apolipoprotein(a) Size Polymorphism in African Americans
In 165 African Americans who reduced saturated fat intake from 16% to 6% of calories (an average American diet shifted to a DASH-type diet), Lp(a) rose by 24% on average. Lp(a) increases did not differ significantly by presence of a small atherogenic apo(a) size (22 kringles or fewer), by single versus two expressed isoforms, or by isoform dominance pattern (p > 0.05 for all), but the magnitude of increase did differ significantly across tertiles of combined kringle sizes (p = 0.006 for trend), and baseline Lp(a) on the higher-saturated-fat diet independently predicted the size of the subsequent change (p < 0.05). Individuals with smaller apo(a) isoforms reached higher post-intervention Lp(a), in some cases enough to reclassify cardiovascular risk. The findings show that a standard heart-healthy dietary change can meaningfully raise Lp(a), an effect apo(a) size only partly explains.
Original abstract
Background/Objectives: An elevated lipoprotein(a) [Lp(a)] level, which is a prevalent cardiovascular risk factor, is genetically determined by a size polymorphism of its apolipoprotein(a) [apo(a)] component. Despite its genetic control, Lp(a) level increases in response to dietary saturated fat (SFA) reduction. We tested the roles of apo(a) size and characteristics in modulating Lp(a) response to SFA reduction.
Methods: We assessed apo(a) characteristics in 165 African Americans experiencing a 24% Lp(a) increase resulting from SFA reduction [16% at an average American Diet diet (AAD) to 6% at a DASH-type diet]. Apo(a) effects were tested based on the following factors: (1) the presence of a small atherogenic size (≤22 kringles), (2) phenotype (single or two isoforms), (3) isoform dominance, and (4) tertiles of combined kringle sizes.
Results: There were no significant differences in Lp(a) increases between carriers vs. non-carriers of a small apo(a), between those with a single vs. two expressed isoforms, or in those with differing isoform dominance patterns (p > 0.05 for all). The extent of Lp(a) increase differed across increasing tertiles of combined kringle sizes (p = 0.006 for trend). In a multivariate model, the AAD Lp(a) level was a significant predictor of Lp(a) changes (p < 0.05). Relative increases in the allele-specific apo(a) level-an Lp(a) level associated with a defined apo(a) size-were similar across the apo(a) size spectrum.
Conclusions: Reducing dietary SFA intake results in a 24% increase in Lp(a) level in African Americans across apo(a) sizes. Individuals with smaller apo(a) sizes reached an elevated Lp(a) level post-intervention compared to those with larger sizes, in some cases resulting in cardiovascular risk reclassification.
Summary written by lp-a.org from the published abstract; figures as published. Page updated 18 August 2026. Methods.