Alanine Unit Converter
Alanine Unit Converter
Convert alanine between mg/dL and µmol/L, with fasting reference intervals by age — and the pairing that gives the number its meaning, because alanine is one transamination away from pyruvate and is read beside the lactate.
Alanine converter
mg/dL ⇄ µmol/LAlanine 3.0 mg/dL on a fasting plasma amino acid profile, read against the adult interval
Formula and conversion factor
mg/dL = µmol/L ÷ 112.246
- 112.246
- derived from the molecular weight of L-alanine, 89.09 Da. Alanine is the second smallest amino acid, so its factor is the second largest of the twenty
- 450 µmol/L
- the absolute alanine above which the Nijmegen protocol counts a point towards mitochondrial disease. It is a work-up threshold, not an upper limit of normal, and it sits inside the adult reference interval
- alanine : lysine
- normally below 3:1. A ratio above that is taken as true hyperalaninaemia rather than a generally concentrated profile, which is why the ratio is read as well as the absolute value
- read with lactate
- alanine is the transamination product of pyruvate. The two rise together when pyruvate cannot be oxidised, and that pairing is what a raised alanine is actually asking about
Worked example
Alanine 3.0 mg/dL on a fasting plasma amino acid profile, read against the adult interval
3.0 × 112.246 = 336.74 µmol/L, reported as 337 µmol/L
Within the Mayo adult interval of 200–579 µmol/L used here, and within Labcorp's 125–564 µmol/L as well
But below the 450 µmol/L the Nijmegen protocol counts as a raised alanine — so a result can be unremarkable against the reference interval and still sit below a work-up threshold that is lower than the reference upper limit
The number that decides how to read it is not on this page: the lactate from the same sample. 337 µmol/L with a lactate of 1.2 mmol/L says nothing; the same alanine with a lactate of 4 mmol/L says measure pyruvate too
Two published adult intervals, and the work-up threshold that sits inside them
| Source | Adult (µmol/L) | Children (µmol/L) | Youngest band (µmol/L) |
|---|---|---|---|
| Mayo Clinic Laboratories — fasting | 200 – 579 (≥18 y) | 144 – 557 (2–17 y) | 139 – 474 (<24 months) |
| Labcorp | 124.8 – 564.2 (>15 y) | 155.8 – 597.3 (2–15 y) | 121.0 – 571.0 (0–30 days) |
| Nijmegen mitochondrial protocol — work-up threshold, not a reference limit | > 450 counts as raised | > 450 | > 450 |
| Alanine : lysine ratio — normal | < 3 : 1 | < 3 : 1 | < 3 : 1 |
The glucose–alanine cycle, and why the lactate is the other half of the answer
| Step | What happens | Why it matters here |
|---|---|---|
| Muscle protein breaks down | Amino groups are transferred onto pyruvate to make alanine | Alanine is the vehicle that carries nitrogen out of muscle without carrying free ammonia |
| Alanine travels to the liver | The liver transaminates it back to pyruvate and makes glucose from it | This is the glucose–alanine cycle. Alanine is the principal gluconeogenic amino acid |
| Pyruvate cannot be oxidised | It accumulates, and equilibrates with both lactate and alanine | A mitochondrial or pyruvate metabolism disorder therefore raises alanine and lactate together |
| Blood is left before separation | Red cells keep making lactate, and most amino acids drift upwards | A raised alanine with a raised lactate can also be a handling artefact. Prompt separation is what tells the two apart |
Alanine is a question about pyruvate
Alanine is a non-essential amino acid and the principal gluconeogenic one. When muscle protein is broken down, amino groups are transferred onto pyruvate to form alanine, which travels to the liver, is transaminated back to pyruvate and is used to make glucose. That round trip is the glucose–alanine cycle, and it is how nitrogen leaves muscle without free ammonia having to travel in the blood. The arithmetic is straightforward: 1 mg/dL is 112.25 µmol/L, from a molecular weight of 89.09 Da.
Because alanine sits one transamination away from pyruvate, it moves with pyruvate. If pyruvate cannot be oxidised — a defect of the respiratory chain, of pyruvate dehydrogenase, or of pyruvate carboxylase — it accumulates and equilibrates into both lactate and alanine. That is why a raised alanine found alongside a raised lactate is a different finding from a raised alanine on its own, and why the Nijmegen diagnostic protocol counts an alanine above 450 µmol/L towards the likelihood of mitochondrial disease. That 450 is a work-up threshold rather than an upper limit of normal, and it sits inside the published adult reference interval, so it will flag values a laboratory reports as normal.
The reference intervals themselves need reading with care. Mayo publishes 200–579 µmol/L for adults and states explicitly that its values are for fasting patients; Labcorp publishes 124.8–564.2 µmol/L for anyone over 15. They disagree by 75 µmol/L at the lower limit. Intervals also differ by age, and a profile taken after a feed, or from blood left standing before the plasma was separated, is not comparable with either. Plasma amino acids are taken fasting — in an infant, immediately before a feed or at the interval the metabolic service specifies — and separated promptly, because concentrations shift with feeding and again in the tube.
What follows is modest and worth saying plainly. An alanine on its own is a weak signal. It becomes informative when it is read with the lactate from the same sample, with the alanine to lysine ratio that separates a truly raised alanine from a generally concentrated profile, and with the rest of the amino acid pattern. Nothing on this page is a diagnosis, and the pairing it points at leads to a lactate and pyruvate measured together rather than to a conclusion.
Frequently asked questions
How do I convert alanine from mg/dL to µmol/L?
Multiply by 112.246, derived from the molecular weight of alanine, 89.09 Da. An alanine of 3.0 mg/dL is 337 µmol/L. To go the other way, divide the µmol/L figure by 112.246.
What is a normal alanine level?
There is no single figure. Mayo publishes 200–579 µmol/L for fasting adults, Labcorp 124.8–564.2 µmol/L for anyone over 15, and both publish different bands for children and infants. Use the interval your own laboratory prints for that age, on a fasting sample.
What does a raised alanine mean?
On its own, often very little — a non-fasting sample or delayed separation will do it. Read with the lactate it means more: alanine is one transamination from pyruvate, so a raised alanine with a raised lactate points towards a mitochondrial or pyruvate metabolism disorder and is a reason to measure lactate and pyruvate together.
Why does the mitochondrial threshold of 450 µmol/L sit inside the normal range?
Because it is a work-up threshold rather than an upper limit of normal. The Nijmegen protocol counts an alanine above 450 µmol/L as one factor among several towards the likelihood of mitochondrial disease; a threshold set to catch a disorder early is deliberately lower than the reference upper limit, and it is not evidence of disease by itself.
Does the sample have to be fasting?
Yes. Published reference intervals assume a fasting sample, amino acid concentrations shift with feeding, and most amino acids drift upwards in blood left standing before the plasma is separated. In an infant the sample is taken immediately before a feed, or at the interval the metabolic service specifies, and sent promptly.
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References
- Parikh S, Goldstein A, Koenig MK, et al. Diagnosis and management of mitochondrial disease: a consensus statement from the Mitochondrial Medicine Society. Genet Med. 2015;17(9):689–701.
- Haas RH, Parikh S, Falk MJ, et al. The in-depth evaluation of suspected mitochondrial disease. Mol Genet Metab. 2008;94(1):16–37.
- Davis JS, Darcy CJ, Piera K, et al. Ex-vivo changes in amino acid concentrations from blood stored at room temperature or on ice: implications for arginine and taurine measurements. BMC Clin Pathol. 2009;9:10.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.