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Johan Stausland's avatar

Hi Jess. The conversion is quite complex, so I asked chat GPT and grok to do the conversion. Here is grok's answer:

To convert from micrograms per gram of hemoglobin (μg/gHb) to micromoles per liter (μmol/L), you need to account for the substance’s molecular weight, the concentration of hemoglobin in the blood, and the units involved. This type of conversion often comes up in medical or biochemical contexts—like measuring hormones, vitamins, or metabolites relative to hemoglobin and then expressing them in a standard concentration. Let’s break it down step-by-step.

### Step 1: Understand the Units

- **μg/gHb**: Micrograms (μg) of a substance per gram of hemoglobin (gHb). This is a mass-per-mass ratio tied to hemoglobin content.

- **μmol/L**: Micromoles (μmol) of a substance per liter (L) of solution (typically blood or plasma). This is a molar concentration.

### Step 2: Key Factors Needed

1. **Molecular Weight (MW)**: The substance’s molecular weight in grams per mole (g/mol). You need this to convert mass (μg) to moles (μmol).

2. **Hemoglobin Concentration (Hb)**: The hemoglobin level in blood, typically in grams per liter (g/L). Normal ranges are around 120–160 g/L (women) or 130–170 g/L (men), but you’d use a specific value if known.

3. **Unit Conversion**: Adjust from grams of hemoglobin to liters of blood and from micrograms to micromoles.

### Step 3: Conversion Formula

The general process is:

1. Convert μg/gHb to μg/L by multiplying by the hemoglobin concentration (g/L).

2. Convert μg/L to μmol/L by dividing by the molecular weight (g/mol) and adjusting for unit prefixes (μg to μmol).

Formula:

\[

\text{Concentration (μmol/L)} = \frac{\text{Concentration (μg/gHb)} \times \text{Hb (g/L)}}{\text{MW (g/mol)}} \times 1

\]

- The “× 1” is because μg (10⁻⁶ g) to μmol (10⁻⁶ mol) cancels out when dividing by g/mol, simplifying the units.

### Step 4: Example

Let’s say you’re converting a substance with:

- Concentration = 50 μg/gHb

- Molecular Weight = 100 g/mol (e.g., a hypothetical compound)

- Hemoglobin = 150 g/L (a typical value)

1. Convert to μg/L:

\[

50 \, \text{μg/gHb} \times 150 \, \text{g/L} = 7500 \, \text{μg/L}

\]

2. Convert to μmol/L:

\[

\frac{7500 \, \text{μg/L}}{100 \, \text{g/mol}} = 75 \, \text{μmol/L}

\]

### Step 5: Notes

- **Substance-Specific**: You didn’t specify a substance, so I can’t plug in an exact MW. For example, testosterone’s MW is ~288 g/mol, vitamin B12’s is ~1355 g/mol—results vary widely.

- **Hb Variability**: If you know your hemoglobin level (e.g., from a blood test), use it. Otherwise, 140 g/L is a decent average estimate.

- **Context**: If this ties to your earlier questions (e.g., testosterone or sleep-related markers), let me know the substance for precision.

### Quick Answer

To convert:

\[

\text{μmol/L} = \frac{\text{μg/gHb} \times \text{Hb (g/L)}}{\text{MW (g/mol)}}

\]

Plug in your values: the μg/gHb number, the substance’s MW, and your Hb in g/L. Got a specific case in mind? Give me those details, and I’ll run it for you!

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Jess Pan's avatar

How do you convert the units from DoNotAge (ug/gHb) to the units in the research study mentioned (μmol/L). I have a different issue with my results - mine were far too HIGH (I've been supplementing). My level is at 200 ug/gHb (upper normal limit is 160) but they use such a weird unit that I can't find any other research or charts that match this unit to compare with others - and I'm slightly worried that mine is far too high. I'd love to know how to convert to more traditional measurements... - thank you so much!! good luck in your journey!

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