Plant Foods and Plant-Derived Bioactive Compounds for Lipid Management in Adults with Familial Hypercholesterolemia: A Systematic Review

Background: Familial hypercholesterolemia (FH) is an inherited disorder characterized by lifelong markedly elevated low-density lipoprotein cholesterol (LDL-C) concentrations from an early age and increased risk of premature atherosclerotic cardiovascular disease. Plant foods may provide lipid-lowering benefits; however, evidence in adults with FH is limited. Objective: We sought to evaluate the effects of plant foods and plant-derived compounds on lipid profiles in adults with FH. Methods: CINAHL, PubMed, and Scopus were systematically searched for studies investigating plant-based interventions in adults with FH. The primary outcomes assessed included circulating total cholesterol (TC), triglyceride (TG), LDL-C, high-density lipoprotein cholesterol (HDL-C), and apolipoprotein B (ApoB). Eighteen studies met the inclusion criteria. Due to heterogeneity in study design, interventions, and outcomes, findings were synthesized narratively. Result: Intervention studies consisted of plant sterols/stanols (n = 6), soy protein (n = 4), soluble dietary fiber (SDF) (n = 3), and whole foods (n = 5). Most participants had heterozygous type IIa FH and were not receiving lipid-lowering medication. Plant-based interventions consistently reduced TC and LDL-C. Plant sterol/stanol and SDF interventions demonstrated LDL-C-lowering effects of 8–21% and 12–22%, respectively. Soy protein lowered TC when substituted for animal protein. Few studies (n = 5) and small sample sizes (8–15 participants) suggested modest LDL-C-lowering effects (6–18%) of prickly pear and alfalfa seeds. Effects on HDL-C, TG, and ApoB showed conflicting or non-significant findings. Conclusions: Plant-based interventions suggest lipid-lowering benefits in adults with FH. However, evidence was limited by few studies, small sample sizes, short durations, and heterogeneous methodologies. Targeted plant-based dietary strategies may offer a practical adjunct to conventional therapy for improving lipid management in adults with FH.