Source: https://guthlabs.ai/docs/instruments/glycemic-load-calculator/mechanism/

instrument mechanism / verified-clean

# Glycemic Load Calculator mechanism

The inspectable method record for Glycemic Load Calculator, kept separate from implementation and qualification.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Model scope

The core arithmetic is correct, and the existing educational-not-medical-advice label is appropriate. Release requires explicit category thresholds, a definition of carbohydrate grams as available/digestible carbohydrate, a stated GI reference convention, and handling for missing or undefined GI values.

- GL=(GI×carb_g)/100 is the standard glycemic-load formula when GI is the food's GI relative to the glucose reference scale (glucose=100) and carb_g means grams of available/digestible carbohydrate in the stated portion.

- The category thresholds are not specified. A common convention is low ≤10, medium 11–19, and high ≥20, but the instrument must explicitly publish its chosen boundary rules.

- The carbohydrate input is ambiguous: total carbohydrate versus available carbohydrate (total carbohydrate minus fiber and sometimes sugar alcohols). Standard GL calculations generally use available/digestible carbohydrate.

- GI is highly dependent on food variety, preparation, ripeness, processing, and test protocol; a lookup value must identify the food form and source convention.

## Units and conventions

- GI is dimensionless and uses the glucose-reference scale, with glucose assigned GI=100.

- carb_g is grams of available/digestible carbohydrate in exactly the portion being evaluated, not grams per 100 g unless the portion is 100 g.

- The worked category outputs assume the conventional thresholds low ≤10, medium 11–19, and high ≥20.

- GI should normally be constrained to 0–100; carbohydrate grams should be nonnegative.

## Inspectable vector

One of 4 source-bound review vectors:

````
{
  "inputs": {
    "food": "glucose solution",
    "glycemic_index": 100,
    "carbohydrate_g": 25,
    "portion_description": "portion containing 25 g available carbohydrate"
  },
  "expected_outputs": {
    "glycemic_load": 25,
    "category": "high"
  },
  "reference_data": {
    "food": "glucose",
    "glycemic_index": 100,
    "source_convention": "International GI reference convention; glucose reference assigned GI=100 (widely tabulated standard value)"
  },
  "working": "GL=(GI×carb_g)/100=(100×25)/100=2500/100=25. Using low ≤10, medium 11–19, high ≥20: 25 is high."
}
````

## Failure boundary

**BREAK_CLAIMED** · SELF_FLAGGED

The extreme-magnitude vector causes mathematical overflow in ordinary floating-point arithmetic, yielding Infinity or a non-finite result unless inputs are rejected or arbitrary-precision arithmetic is used. Category thresholds are also unspecified, and unit ambiguity can change the result substantially.

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/glycemic-load-calculator/>)[03**Implementation**](<https://guthlabs.ai/docs/instruments/glycemic-load-calculator/implementation/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/glycemic-load-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche7/tranche7-results.json`

- `BOUNDARY_HAZARD_CATALOG.json`