👉 We spend decades arguing about how low to push LDL-C 👆 Almost no one asks the obvious question: 🤔 How much LDL-C did our ancestors actually have? The evidence exists — five independent lines, all converging on the same uncomfortable answer. 1️⃣ The term newborn. Before any dietary or metabolic influence, a healthy neonate arrives with LDL-C of ~30–50 mg/dL. That is the LDLR operating without environmental interference. Everything that rises after birth is acquired. 2️⃣ The Tsimane (Kaplan et al., Lancet 2017) — forager-horticulturalists of the Bolivian Amazon — have a LDL-C between 70 to 90 mg/dL and the lowest prevalence of coronary atherosclerosis ever recorded in any human population. Five times less than the U.S. in adults over 75. And their LDL is rising as roads and processed food arrive. 3️⃣ PCSK9 loss-of-function variants. African American carriers of nonsense mutations (Y142X/C679X, ~2% frequency): −28% LDL-C and −88% CHD risk over 15 years (Cohen et al., NEJM 2006). Homozygous LOF carriers live with LDL-C of ~15–30 mg/dL. Perfectly healthy. Nature already ran the trial. 4️⃣ Evolutionary genetics. Recent positive selection signals exist on gain-of-function PCSK9 variants that raise LDL-C — likely adaptive in food-scarce ancestral environments. Modern hypercholesterolemia is not "normal." It is an ancestral survival advantage turned pathological by evolutionary mismatch. 5️⃣ Great apes in natural habitat: ~40–70 mg/dL LDL-C. Same genome. Different environment. 👆 Bonus — Lp(a). The KIV-2 repeat expansion that raises Lp(a) is a derived, recent variant. Low-Lp(a) alleles are ancestral. Elevated Lp(a) is a textbook antagonistic pleiotropy signal — possibly protective against bleeding early in life, atherogenic over decades 📍The convergent estimate: ancestral LDL-C was ~30–70 mg/dL. 📍An LDL-C of 130 mg/dL is not "normal." It is normal for a Western society in evolutionary mismatch. Targets of <55 mg/dL in high-risk patients — which still feel aggressive to many clinicians — are, ironically, closer to the ancestral phenotype than what we call "normal LDL" in daily practice. 🤔 The question is not "is it safe to lower LDL this much?" The question is: why did we let it rise this high? @society_eas @nationallipid