Clinical Medicine & Physiology
Lipid Accumulation Product (LAP) Calculator: Kahn Sex-Specific Waist-Triglyceride Formula
Quantify ectopic lipid overaccumulation and MASLD / hepatic steatosis risk using Henry S. Kahn’s (2005) sex-specific Lipid Accumulation Product: LAP = (WC_cm - 65) * TG_mmol_L in men and (WC_cm - 58) * TG_mmol_L in women.
Capture simultaneous anatomical waist expansion and hypertriglyceridemic spillover!
Formulated by CDC epidemiologist Henry S. Kahn (2005, BMC Cardiovascular Disorders) from NHANES III data, the Lipid Accumulation Product (LAP) replaces categorical "hypertriglyceridemic waist" yes/no cutoffs with a continuous product above sex-specific minimum physiological waist baselines (65 cm in adult men and 58 cm in adult women, reflecting abdominal muscle, viscera, and lumbar spine):
With fasting triglycerides expressed in mmol/L (divide mg/dL by 88.57), LAP_men = (WC_cm - 65) * TG_mmol_L and LAP_women = (WC_cm - 58) * TG_mmol_L (cm·mmol/L)! Because LAP rises nonlinearly only when BOTH central subcutaneous/visceral storage is full AND circulating triglycerides accumulate in plasma, LAP >= 30–40 cm·mmol/L strongly predicts hepatic steatosis (MASLD/NAFLD), insulin resistance, and incident Type 2 Diabetes!
| Adult Subject (WC in cm, Fasting TG in mmol/L) | Excess Waist Above Minimum | Kahn LAP (cm·mmol/L) | Ectopic Lipid Interpretation |
|---|---|---|---|
| Lean Male (WC = 79 cm, TG = 0.90 mmol/L) | 14 cm above 65 cm | 12.60 | Low ectopic lipid burden |
| Central-Gain Male (WC = 101 cm, TG = 2.20 mmol/L) | 36 cm above 65 cm | 79.20 | High ectopic / hepatic lipid spillover |
| Central-Gain Female (WC = 90 cm, TG = 1.85 mmol/L) | 32 cm above 58 cm | 59.20 | Elevated MASLD & metabolic syndrome risk |
Kahn (2005) Sex-Specific Lipid Accumulation Product (LAP, cm·mmol/L)
Evaluates (WC_cm - 65) * TG_mmol_L for Men ("M", WC > 65 cm) and (WC_cm - 58) * TG_mmol_L for Women ("F", WC > 58 cm).
=IF(OR(AND(B2 <> "M", B2 <> "F"), B3 <= IF(B2 = "M", 65, 58), B3 > 200, B4 <= 0, B4 > 35), "Requires Sex M/F, Waist > Sex Minimum (65 M / 58 F cm), and TG > 0 mmol/L", ROUND((B3 - IF(B2 = "M", 65, 58)) * B4, 2))LAP Ectopic Lipid Overaccumulation Screening Tier (>= 40 cm·mmol/L)
Flags LAP >= 40 cm·mmol/L for elevated hepatic steatosis and cardiometabolic lipid spillover.
=IF(OR(AND(B2 <> "M", B2 <> "F"), B3 <= IF(B2 = "M", 65, 58), B3 > 200, B4 <= 0, B4 > 35), "Requires Sex M/F, Waist > Sex Minimum (65 M / 58 F cm), and TG > 0 mmol/L", IF((B3 - IF(B2 = "M", 65, 58)) * B4 >= 40, "LAP >= 40: Elevated Ectopic Lipid & MASLD Risk", "LAP < 40: Below High-Risk Lipid Spillover Cutoff"))Try the example
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