Testing for Prevention: What Blood Tests Actually Matter, and Why Your GP Is Still the Expert

He walked into Bay Four holding eight pages of printed lab results. He was 43, fit, did CrossFit five times a week, and had spent real money on a direct-to-consumer “longevity subscription” panel. His LDL was 170 mg/dL — meaningfully high. When I raised it, he told me it didn’t matter. His LDL fractionation showed mostly large, fluffy particles. Those are the harmless kind. Right? Wrong. And in this episode, Dr Cois — Emergency Physician and creator of drcois.com — explains exactly why — and what the brand-new 2026 ACC/AHA Dyslipidemia Guideline actually says about it.In this episode: --- How the USPSTF develops prevention guidelines: the 5-step evidence review, letter-graded recommendations, and why this is nothing like a social media hot take --- The ADA’s 2026 Standards of Care: when to screen for prediabetes and diabetes, what HbA1c targets mean, and how lifestyle change cuts your risk of progression by 50%--- The 2026 AHA/ACC Dyslipidemia Guideline — five major changes: restored LDL targets (100, 70, and 55 mg/dL by risk tier), the new PREVENT risk equations, Lp(a) screening for all adults, ApoB’s expanded role, and the shift to earlier intervention--- Myth 1: Large fluffy LDL is harmless — what the prospective evidence actually shows, and why ApoB is the more important number--- Myth 2: The “get your labs,b uy our supplements” model — why unregulated supplement recommendations from lab companies represent a structural conflict of interest--- A plain-language guide to every blood test that matters in primary prevention: CBC, CMP, HbA1c, lipid panel, ApoB, Lp(a), TSH, vitamin D, B12, and iron — and how your Tier 1 habits move these numbers--- What to ask your GP at your next appointment Your primary care physician is the original longevity expert. The USPSTF, the ADA, and the AHA have spent years in methodological rigour so that your doctor knows exactly which tests to run, when, and what to do with the results. That system is imperfect. But it is evidence-based, publicly accountable, and not trying to sell you a supplement.Use it. Fewer bad days. More good decades.Companion blog post + full references at drcois.com