The Early Developmental Origins of Atherosclerosis: Lipid Trajectories, Pathobiological Determinants, and the Lifelong Burden of Cardiovascular Risk from Infancy
Introduction
The understanding of atherosclerotic cardiovascular diseaseCardiovascular disease is the umbrella term for problems with the heart and blood vessels, including heart attacks, strokes, and blocked leg arteries. (ASCVD) has undergone a profound transformation over the last century, shifting from a perceived inevitable consequence of aging to a recognized life-course metabolic progression that commences during fetal development and infancy.[1] While the clinical manifestations of disease, such as myocardial infarctionSee Heart Attack for the full entry., strokeA stroke happens when blood flow to part of the brain stops, either from a blockage or from bleeding., and peripheral vascular syndromes, typically emerge in middle or late adulthood, the silent incubation of these conditions spans decades.[2–4] This developmental paradigm is supported by longitudinal epidemiological cohorts and post-mortem investigations, which collectively indicate that the foundations of cardiovascular pathology are established in the earliest stages of human existence.[2–5] So do babies need statinsA statin slows the enzyme your liver uses to make cholesterol. Your liver responds by pulling more cholesterol out of your blood, which is where the real benefit comes from.? Let’s see!
Physiological Trajectories of Plasma Lipids in the First Two Years of Life
The neonatal period and early infancy represent a phase of dramatic metabolic transition characterized by rapid physiological adaptation to extrauterine life. At birth, cholesterolCholesterol is a waxy substance your body needs. It goes into cell walls, hormones, vitamin D, and the bile that digests your food. You would die without it. concentrations in umbilical cord blood are substantially lower than those observed in adult populations.[6] However, these levels are highly dynamic and follow distinct trajectories during the first 24 months of life.
Stepwise Increases and Achievement of Early Baseline Levels
Concentrations of atherogenic lipid traits—including low-density lipoproteinA lipoprotein is a tiny package that carries fat and cholesterol through your bloodstream. Since fat won't dissolve in water, it needs a protein wrapper to travel. cholesterol (LDL-C), non-HDL-C, apolipoproteinAn apolipoprotein is a protein attached to a fat-carrying particle in your blood. Fat and water don't mix, so these proteins act like a wrapper that lets fat travel safely through the bloodstream. B, and lipoprotein(a)Lipoprotein(a), written Lp(a) and said "L-P-little-a," is an LDL-like particle with an extra sticky protein attached.—exhibit a consistent stepwise increase from birth through the first 16 months of life.[6] Data from the Copenhagen Baby Heart StudyA large Danish cohort study that analyzed lipid and lipoprotein concentrations in over 13,000 cord blood samples with longitudinal follow-up, providing normative reference data for cholesterol trajectories from birth through the first 14–16 months of life., incorporating 13,354 cord blood samples with longitudinal venous follow-up, demonstrate that by 14–16 months, total cholesterolTotal cholesterol adds together the cholesterol in all your particles, harmful and helpful alike. and LDL-C concentrations approach steady-state levels similar to those observed in adulthood.[1,6]
This observation suggests that the baseline lipid phenotype may be established far earlier than previously hypothesized, constituting a neglected resource for early cardiovascular risk identification.[1]
Variability in Non-Atherogenic Traits
Not all lipid parameters follow a linear rise. Total cholesterol and triglyceridesTriglycerides are the main form of fat in your blood and in your body's storage. increase sharply in early infancy and subsequently stabilize, whereas HDL-C may rise initially and decline modestly during dietary transition from lipid-rich milk to mixed diets.[6] This variability reflects the metabolic plasticity of infancy as nutritional substrates shift.
Normal Reference Values for Infants and Children
Because lipid levels change rapidly in early life, interpretation requires age-specific reference ranges.[6,7]
Neonatal and Infantile Lipid Ranges (0–24 Months)
Lipid levels at birth are markedly lower than adult thresholds but rise rapidly during infancy, reaching near–adult steady-state concentrations by 14–16 months.[1,6]
Table 1. Neonatal and Infant Lipid Reference Values (Copenhagen Baby Heart Study)[6]
| Age Group | Total Cholesterol (mg/dL) Median (IQR) | LDL-C (mg/dL) Median (IQR) | HDL-C (mg/dL) Median (IQR) | Triglycerides (mg/dL) Median (IQR) |
| Neonates (birth) | 77 (70–93) | 32 (24–39) | 33 (27–41) | 28 (24–34) |
| Infancy (2 months) | 147 (128–166) | 65 (52–79) | 50 (41–62) | 62 (48–84) |
| Early toddler (14–16 months) | 143 (124–162) | 84 (70–103) | 36 (30–45) | 43 (30–60) |
Note: Values reported in mmol/L in Nielsen et al. and converted to mg/dL.[6]
Pediatric Lipid Classification (Ages 2–19 Years)
After age 2 years, lipid interpretation shifts from developmental physiology to cardiovascular risk thresholds. NHLBI pediatric guidelines define the following categories.[7]
Table 2. Pediatric Lipid Classification Thresholds (2–19 Years)[7]
| Classification | Total Cholesterol (mg/dL) | LDL-C (mg/dL) | HDL-C (mg/dL) | Triglycerides (mg/dL) |
| Acceptable | <170 | <110 | >45 | <75 (0–9y) / <90 (10–19y) |
| Borderline | 170–199 | 110–129 | 40–45 | 75–99 (0–9y) / 90–129 (10–19y) |
| High/Abnormal | ≥200 | ≥130 | <40 | ≥100 (0–9y) / ≥130 (10–19y) |
Biological and Environmental Determinants of Infantile Lipid Levels
High cholesterol in infancy reflects a synthesis of biological maturity, genetic inheritance, and early environmental exposure.
Biological Sex and Maternal Health
Female infants exhibit higher total cholesterol, LDL-C, and apoBApoB is a protein that sits on the outside of every cholesterol particle that can get stuck in your artery wall and cause plaque. Each of those particles carries exactly one ApoB. concentrations than males, differences detectable from birth and persisting through early childhood.[1] Maternal hypercholesterolemiaHypercholesterolemia is an abnormally elevated level of cholesterol-carrying particles in the blood, typically caused in primate experiments by feeding a diet high in dietary cholesterol and saturated fat, and associated with accelerated plaque formation in artery walls. during pregnancy is associated with accelerated early atherogenesisAtherogenesis is the step-by-step process of a plaque forming. in offspring.[8] Epigenetic analyses of fetal vascular tissue show altered epigenetic regulation of cholesterol-homeostasis pathways (including regulatory regions of SREBP2) in association with early fetal atherosclerotic lesionsIn cardiology, a lesion refers to a discrete area of atherosclerotic plaque narrowing a coronary artery, typically described by the percentage of luminal obstruction it causes. The article describes four residual lesions too small in vessel diameter to accept a stent after the most critical one was treated., supporting fetal metabolic imprinting as a mechanistic framework.[9]
The Nutritional Paradox of Breastfeeding
Breastfed infants often show higher cholesterol concentrations than formula-fed peers, a physiologic response to the cholesterol-rich composition of human milk.[6] Early-life lipid exposure is consistent with lipid trackingThe tendency for an individual's lipid concentrations to maintain their relative rank within a population over time, so that a child with high LDL-C is likely to remain relatively high as an adult; documented from infancy through adulthood in longitudinal studies such as the Bogalusa Heart Study and Young Finns Study. across the life course.[10]
Atherosclerosis in Infancy and Youth: Pathological Evidence
AtherosclerosisAtherosclerosis is the disease behind most heart attacks and many strokes. Cholesterol particles get stuck in the wall of an artery, the body sends immune cells to clean up, and over years that mess hardens into plaque. begins as fatty streaksA fatty streak is the earliest visible stage of atherosclerosis — a flat yellow smear of cholesterol-filled immune cells just under the artery lining.—subintimal accumulations of foam cellsA foam cell is an immune cell that has eaten so much trapped cholesterol that it swells up and looks foamy under a microscope. and lymphocytes—that can be identified early in life.[2–4] Autopsy studies demonstrate that early lesions are detectable in infancy and become increasingly prevalent through childhood.[4,11,12]
Pathobiological Determinants of Atherosclerosis in Youth (PDAY)
The PDAY studyThe Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study was a pathological study that examined the coronary arteries and aortas of young people aged 15–34 who died from unrelated causes such as accidents; it demonstrated that early atherosclerotic lesions — fatty streaks and more advanced plaques — were already present in most adolescents and young adults, decades before any cli… remains foundational in pediatric cardiovascular pathology. PDAYPDAY, short for Pathobiological Determinants of Atherosclerosis in Youth, examined the arteries of young people aged 15 to 34 who died of other causes. collected arterial specimens from 2,876 individuals aged 15–34 years who died of external causes.[2] Coronary and aortic lesions were present in adolescence, and lesion severity correlated strongly with modifiable risk factorsA risk factor is something that raises your chance of developing a disease — high cholesterol particles, high blood pressure, smoking, diabetes, family history..[2–4]
Risk scoring derived from PDAY predicts later coronary arteryAn artery is a blood vessel that carries blood away from the heart to the rest of the body. calcificationCalcification is when calcium gets deposited into a plaque, turning part of it hard and bony. in adulthood, validating the clinical relevance of early-life risk burden.[13]
Historical Trends in Pediatric Lipids
Mean total cholesterol levels among US youths declined between 1988 and 2010, with reductions in both mean levels and prevalence of elevated total cholesterol documented in NHANES analyses.[14] However, these improvements are counterbalanced by the obesityObesity means carrying enough excess body fat to affect health. epidemic, which amplifies adverse lipid phenotypes in vulnerable subgroups.[7]
Mechanisms of Age-Related Cholesterol Elevation
Plasma cholesterol rises with aging largely due to reduced fractional clearance of LDLLDL, or low-density lipoprotein, is the main particle that carries cholesterol through your blood — and the main one that gets stuck in artery walls. particles.[15] Aging is associated with declining hepatic LDL receptorThe LDL receptor is a docking port on liver cells that grabs LDL particles out of the blood and pulls them in to be broken down. activity and altered endocrine regulation. Growth hormone influences bile acidBile acids are made by your liver from cholesterol and released into the gut to help digest fat. synthesis through cholesterol 7α-hydroxylase activity, providing mechanistic links between senescence and dyslipidemiaDyslipidemia is the medical word for an unhealthy pattern of fats in the blood. It can mean high LDL, high triglycerides, low HDL, or some combination..[16]
The Evolutionary Heritage of High Plasma Cholesterol
High circulating cholesterol, while harmful in modern environments of caloric abundance, may have conferred survival advantages in ancestral contexts characterized by nutritional scarcity and infectious burden.[17]
Evolutionary Advantages
Energy Security. Genetic variants favoring higher circulating cholesterol may have supported energy storage and reproductive fitness during feast-famine cycles.[18]
Immune Modulation. Membrane cholesterol organizes lipid raftsLipid rafts are cholesterol-enriched microdomains within cell membranes that act as organized platforms for receptor tyrosine kinases, G-protein-coupled receptors, and other signalling molecules. Their integrity depends on adequate membrane cholesterol, underscoring why cholesterol is maintained as a structural asset rather than a fuel source. that cluster antigen receptors on memory T cells, enhancing immune responsiveness.[19] HDLHDL, or high-density lipoprotein, is the particle often called "good cholesterol." It picks up cholesterol from tissues and carries it back to the liver. also binds and neutralizes bacterial toxins such as lipopolysaccharides during infection.[20]
Endocrine Readiness. Cholesterol is the obligate precursor for steroid hormone synthesis, including cortisol, and is essential for adrenal stress adaptation.[21]
Antagonistic PleiotropyAntagonistic pleiotropy is an evolutionary hypothesis in which a gene or biological trait confers a survival or reproductive advantage early in life while becoming harmful later; applied to cardiovascular disease, it suggests that lipid-transport systems that may have offered benefits in ancestral environments become disadvantageous across long modern lifespans of caloric abundance.. Traits conferring early-life survival benefit may persist despite late-life cardiovascular costs.[17]
The Lifelong Burden of Cumulative LDL Exposure
Cardiovascular risk reflects cumulative arterial exposure to atherogenic lipoproteins rather than single time-point measurements.[1,22] Genetic, epidemiologic, and clinical evidence establishes LDL-C as a causal driver of ASCVD, emphasizing the importance of early prevention.[22]
Clinical Management and the Window of Opportunity
Universal lifestyle promotion and targeted screening are central to prevention. NHLBI guidelines recommend universal lipid screening at ages 9–11 years and earlier screening beginning at age 2 in high-risk families.[7]
Universal Lifestyle Interventions
The Cardiovascular Health Integrated Lifestyle Diet (CHILD-1) provides the foundation of primordial preventionPrimordial prevention is a strategy aimed at stopping the development of cardiovascular risk factors in the first place—rather than treating risk factors or existing disease—by keeping atherogenic exposures near zero from birth or early life. It is distinguished from primary prevention, which targets people who already have risk factors but no clinical disease. beginning in early childhood.[7]
- Exclusive breastfeeding when possible[6]
- Delaying solid foods until at least 4 months[7]
- Transition to reduced-fat dairy after 12 months in appropriate contexts[7]
- Total fat intake of ~25–30% of calories after age 2 with saturated fatSaturated fat is the kind that stays solid at room temperature — butter, the fat in red meat, coconut oil, and palm oil. limitation[7]
Pharmacologic therapy is reserved for older children with severe dyslipidemia, particularly familial hypercholesterolemiaFamilial hypercholesterolemia, or FH, is an inherited condition where the liver cannot clear cholesterol from the blood properly. Levels are very high from birth..[7]
Conclusion
Atherosclerosis is a lifelong process beginning in fetal development and infancy. Early lipid trajectories establish cumulative exposureCumulative exposure is the total amount of harmful cholesterol particles your arteries have been soaked in across your entire life — how high, multiplied by how long. burdens that drive lesion progression from fatty streaks in childhood to fibrous plaquesPlaque is the buildup of cholesterol, immune cells, scar tissue, and calcium inside an artery wall. in adulthood.[2–4] Prevention must therefore begin early—optimizing maternal health, identifying high-risk lipid phenotypes in infancy, and implementing primordial prevention during the developmental window when vascular injury remains minimal and modifiable.[1,7,8] Infants are not eligible for statin therapy at this time but there certainly are things the mother can do when pregnant and after birth to protect her child for years to come.
References
- Holven KB. Plasma cholesterol levels in infancy: a neglected resource. Eur Heart J. 2023;44(42):4419-4421. doi:10.1093/eurheartj/ehad558
- Natural history of aortic and coronary atherosclerotic lesions in youth. Findings from the PDAY Study. Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group. Arterioscler Thromb. 1993;13(9):1291-1298. doi:10.1161/01.atv.13.9.1291
- McGill HC Jr, McMahan CA, Zieske AW, et al. Association of Coronary Heart Disease Risk Factors with microscopic qualities of coronary atherosclerosis in youth. Circulation. 2000;102(4):374-379. doi:10.1161/01.cir.102.4.374
- Strong JP, Malcom GT, McMahan CA, et al. Prevalence and extent of atherosclerosis in adolescents and young adults: implications for prevention from the Pathobiological Determinants of Atherosclerosis in Youth Study. JAMA. 1999;281(8):727-735. doi:10.1001/jama.281.8.727
- Luca AC, David SG, David AG, et al. Atherosclerosis from Newborn to Adult-Epidemiology, Pathological Aspects, and Risk Factors. Life (Basel). 2023;13(10):2056. Published 2023 Oct 14. doi:10.3390/life13102056
- Taageby Nielsen S, Mohr Lytsen R, Strandkjær N, et al. Significance of lipids, lipoproteins, and apolipoproteins during the first 14-16 months of life. Eur Heart J. 2023;44(42):4408-4418. doi:10.1093/eurheartj/ehad547
- Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents; National Heart, Lung, and Blood Institute. Expert panel on integrated guidelines for cardiovascular health and risk reduction in children and adolescents: summary report. Pediatrics. 2011;128 Suppl 5(Suppl 5):S213-S256. doi:10.1542/peds.2009-2107C
- Napoli C, Glass CK, Witztum JL, Deutsch R, D’Armiento FP, Palinski W. Influence of maternal hypercholesterolaemia during pregnancy on progression of early atherosclerotic lesions in childhood: Fate of Early Lesions in Children (FELIC) study. Lancet. 1999;354(9186):1234-1241. doi:10.1016/S0140-6736(99)02131-5
- de Nigris F, Cacciatore F, Mancini FP, et al. Epigenetic Hallmarks of Fetal Early Atherosclerotic Lesions in Humans. JAMA Cardiol. 2018;3(12):1184-1191. doi:10.1001/jamacardio.2018.3546
- Øyri LKL, Bogsrud MP, Kristiansen AL, et al. Cholesterol at ages 6, 12 and 24 months: Tracking and associations with diet and maternal cholesterol in the Infant Cholesterol Study. Atherosclerosis. 2021;326:11-16. doi:10.1016/j.atherosclerosis.2021.04.017
- Tanaka K, Masuda J, Imamura T, et al. A nation-wide study of atherosclerosis in infants, children and young adults in Japan. Atherosclerosis. 1988;72(2-3):143-156. doi:10.1016/0021-9150(88)90075-5
- Françoso LA, Coates V. Anatomicopathological evidence of the beginning of atherosclerosis in infancy and adolescence. Arq Bras Cardiol. 2002;78(1):131-142.
- Gidding SS, Rana JS, Prendergast C, et al. Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Risk Score in Young Adults Predicts Coronary Artery and Abdominal Aorta Calcium in Middle Age: The CARDIA Study. Circulation. 2016;133(2):139-146. doi:10.1161/CIRCULATIONAHA.115.018042
- Kit BK, Carroll MD, Lacher DA, Sorlie PD, DeJesus JM, Ogden C. Trends in serum lipids among US youths aged 6 to 19 years, 1988-2010. JAMA. 2012;308(6):591-600. doi:10.1001/jama.2012.9136
- Ericsson S, Eriksson M, Vitols S, Einarsson K, Berglund L, Angelin B. Influence of age on the metabolism of plasma low density lipoproteins in healthy males. J Clin Invest. 1991;87(2):591-596. doi:10.1172/JCI115034
- Rudling M, Parini P, Angelin B. Growth hormone and bile acid synthesis. Key role for the activity of hepatic microsomal cholesterol 7alpha-hydroxylase in the rat. J Clin Invest. 1997;99(9):2239-2245. doi:10.1172/JCI119398
- Lea AJ, Clark AG, Dahl AW, et al. Applying an evolutionary mismatch framework to understand disease susceptibility. PLoS Biol. 2023;21(9):e3002311. Published 2023 Sep 11. doi:10.1371/journal.pbio.3002311
- Brassington L, Arner AM, Watowich MM, et al. Integrating the Thrifty Genotype and Evolutionary Mismatch Hypotheses to understand variation in cardiometabolic disease risk. Evol Med Public Health. 2024;12(1):214-226. Published 2024 Jul 31. doi:10.1093/emph/eoae014
- Bietz A, Zhu H, Xue M, Xu C. Cholesterol Metabolism in T Cells. Front Immunol. 2017;8:1664. Published 2017 Nov 27. doi:10.3389/fimmu.2017.01664
- Meilhac O, Tanaka S, Couret D. High-Density Lipoproteins Are Bug Scavengers. Biomolecules. 2020;10(4):598. Published 2020 Apr 12. doi:10.3390/biom10040598
- Gomez-Sanchez CE, Gomez-Sanchez EP. Cholesterol Availability and Adrenal Steroidogenesis. Endocrinology. 2024;165(4):bqae032. doi:10.1210/endocr/bqae032
- Ference BA, Ginsberg HN, Graham I, et al. Low-density lipoproteins cause atherosclerotic cardiovascular disease. 1. Evidence from genetic, epidemiologic, and clinical studies. A consensus statement from the European Atherosclerosis Society Consensus Panel. Eur Heart J. 2017;38(32):2459-2472. doi:10.1093/eurheartj/ehx144



