Interpreting lab results through a functional medicine lens aims to optimize health, not just avoid disease. Traditional lab ranges often aim to identify severe abnormalities, but these ranges don’t necessarily reflect ideal health. Functional medicine advocates for a more personalized and detailed approach that considers factors such as inflammation, insulin sensitivity, and lifestyle (diet, exercise, sleep). This shift acknowledges that “normal” does not mean “optimal” and that general recommendations can often miss critical elements of metabolic health. Functional medicine optimal ranges represent a proactive approach to assessing health risks before they escalate into chronic issues.
Key Markers and Ranges for Optimal Health
- Triglycerides (<80 mg/dL)
High triglycerides can indicate poor insulin sensitivity and metabolic dysfunction. Lower levels reflect efficient fat metabolism and reduced risk of cardiovascular issues. - HDL (50-90 mg/dL)
HDL, or “good cholesterol,” helps clear arterial plaque and reduce cardiovascular risk. Low HDL often points to an inflammatory lifestyle, while levels in this optimal range support heart and metabolic health. - Triglyceride to HDL Ratio (<1.5)
This ratio is a better cardiovascular risk marker than total cholesterol or LDL alone. A ratio higher than 3 is a red flag for metabolic dysfunction. Low ratios, under 1.5, suggest good insulin sensitivity and lower cardiovascular risk. - LDL-A vs. LDL-B
LDL particles come in two forms: large, fluffy LDL-A and small, dense LDL-B. While general medicine often treats high LDL as a statin-worthy risk, only LDL-B correlates strongly with cardiovascular problems. Elevated LDL-A may not pose the same risk, as it’s less prone to oxidative damage. Understanding this distinction prevents unnecessary statin prescriptions and focuses on inflammation and insulin sensitivity as core cardiovascular drivers. - Fasting Glucose (70-85 mg/dL)
Conventional ranges for fasting glucose allow values up to 100 mg/dL, but optimal health falls within 70-85 mg/dL. Higher fasting glucose levels reflect insulin resistance and stress, and optimizing this marker supports metabolic resilience. - Fasting Insulin (2-5 mIU/L)
Fasting insulin over 10 mIU/L signals insulin resistance, and levels over 15 are cause for concern. This marker is often overlooked, yet it’s critical to early intervention for metabolic health. Ideal fasting insulin levels help maintain stable blood sugar and prevent metabolic syndrome. - HOMA-IR (<2)
The Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) is a combined measure of glucose and insulin, directly indicating insulin sensitivity. Values above 2 point toward metabolic dysfunction, while values under 2 are the goal for optimal metabolic health. - Hemoglobin A1C (5-5.4%)
While standard cutoffs label <5.7% as “normal,” functional medicine sees 5-5.4% as optimal. Hemoglobin A1C reveals blood sugar control over 2-3 months, and keeping it low reduces inflammation and risk of type 2 diabetes. - CRP (<0.3 mg/dL)
C-reactive protein (CRP) measures inflammation. Values over 1.0 suggest chronic inflammation, linked to numerous health risks. Lower CRP, under 0.3, indicates reduced systemic inflammation and a healthier immune response. - Vitamin D (40-60 ng/mL)
Vitamin D is essential for immunity, mood, and inflammation control. Levels under 30 ng/mL are common, yet optimal health requires 40-60 ng/mL, especially given its critical role in immune and metabolic function.
Why Standard Recommendations Are Often Misleading
Conventional medicine often emphasizes high LDL or total cholesterol levels as indicators for statins. However, focusing on LDL alone overlooks more significant risk markers, such as high triglycerides, high CRP, and a poor triglyceride-to-HDL ratio. This leads to oversimplified, generalized treatment recommendations that may not address underlying metabolic issues. Statins are sometimes overprescribed when the root cause may actually be an inflammatory lifestyle, poor insulin sensitivity, or nutrient deficiencies that go unaddressed.
Our functional medicine approach prioritizes understanding each marker in the context of overall health and lifestyle. For example, markers like fasting insulin and the triglyceride-to-HDL ratio provide better insight into metabolic health and cardiovascular risk than cholesterol alone. By aiming for these optimal ranges, individuals can take proactive control over their health, addressing potential risks before they progress to disease. In contrast to generalized thresholds, functional markers emphasize metabolic resilience and long-term wellness, guiding better dietary, lifestyle, and therapeutic choices.
