Organic Acid Test Part 5: Amino Acid Metabolites

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“Amino acid metabolites reveal how well your body is turning protein into fuel, neurotransmitters, and detox support.”

 

Amino acids are organic molecules used by living organisms to make proteins. The main elements in amino acids are carbon, hydrogen, oxygen, and nitrogen. Twenty different kinds of amino acids combine to make proteins in our bodies. Our bodies can make some amino acids, but the rest we must get from our food.

In an Organic Acid Test (OAT), the Amino Acid Metabolites section evaluates how well the body is processing, breaking down, and utilising amino acids—the building blocks of proteins. Abnormal levels can reflect issues in digestion, nutrient cofactors, neurotransmitter balance, detoxification, and inherited metabolic conditions.

🔬 Common Metabolites Measured & Their Significance:

🧪 1. Kynurenic Acid & Quinolinic Acid

  • Derived from tryptophan metabolism

  • Reflect the balance between neuroprotective (kynurenic) and neurotoxic (quinolinic) pathways

  • Imbalance may signal:

    • Vitamin B6 or B3 deficiency

    • Inflammation

    • Neurotoxicity or oxidative stress

🧪 2. Homovanillic Acid (HVA)

  • Dopamine breakdown product (from tyrosine)

  • Altered levels suggest:

    • Dopaminergic imbalance (ADHD, Parkinson’s, stress)

    • B6 or iron insufficiency

🧪 3. Vanillylmandelic Acid (VMA)

  • Norepinephrine/epinephrine breakdown product (from tyrosine)

  • High = stress or adrenal overactivation

  • Low = fatigue, adrenal burnout, nutrient depletion

🧪 4. 3-Hydroxyisovaleric Acid

  • Byproduct of leucine metabolism

  • Elevated in:

    • Biotin (B7) deficiency

    • Mitochondrial stress

🧪 5. 2-Hydroxyphenylacetic Acid, 4-Hydroxyphenylacetic Acid, and related compounds

  • From phenylalanine and tyrosine breakdown

  • Elevated in:

    • Dysbiosis (especially Clostridia species)

    • Impaired liver detox

    • Neurotransmitter imbalance

🧪 6. N-Acetylated Amino Acids (e.g., N-acetylaspartic acid)

  • Reflect on amino acid processing in the brain and liver

  • Elevated in:

    • Neurodevelopmental disorders

    • Mitochondrial dysfunction

    • Inborn errors of metabolism

🧪 7. Glutaric Acid, Succinylacetone

  • From lysine, tryptophan metabolism

  • Elevated in:

    • Rare genetic conditions (glutaric aciduria)

    • Carnitine or riboflavin (B2) insufficiency

Low levels of amino acid metabolites are good. Higher levels mean there is impaired enzyme activity, most often due to genetic causes.

Dr Lindenberg comments: “Branched-chain amino acids OK with relatively low tyrosine metabolism.”

3-Hydroxyisobutyric acid                                           5.48 (result)  L / 20 – 118

A low level of 3-Hydroxyisobutyric acid (3-HIBA) may indicate reduced activity in the catabolic pathway of valine, a branched-chain amino acid (BCAA).

🔬 What is 3-Hydroxyisobutyric Acid?

  • A byproduct of valine metabolism

  • Formed during the conversion of valine → succinyl-CoA → energy

  • Dependent on:

    • B-vitamins (especially B2, B3, B5, B6)

    • Magnesium

    • Healthy mitochondrial function

🧠 What Low 3-HIBA May Suggest:

✅ 1. Reduced Valine Metabolism

  • May be due to:

    • Low dietary protein intake

    • Low intake or absorption of valine or other BCAAs

    • Low muscle mass (where BCAA turnover occurs)

    • Low metabolic demand (sedentary state)

✅ 2. Impaired Mitochondrial Beta-Oxidation

  • May point to mitochondrial inefficiency, especially in BCAA oxidation

  • Possible nutrient cofactor insufficiency:

    • Riboflavin (B2) – required by acyl-CoA dehydrogenases

    • Pantothenic acid (B5) – for CoA formation

    • Magnesium – essential for many enzyme functions

✅ 3. Low Anabolic/Catabolic Activity

  • May reflect low metabolic turnover, especially in conditions of:

    • Low energy output

    • Low exercise/muscle activation

    • Hypothyroidism or hypometabolism

✅ 4. Sample Timing or Variability

  • Organic acid excretion can fluctuate day to day.

  • A single low result may not always have clinical significance unless consistent with symptoms or other low metabolites.

Valine: (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It is essential in humans, meaning the body cannot synthesise it; it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, beans and legumes. Leucine, isoleucine, and valine are grouped as branched-chain amino acids or BCAAs.

An interesting fact about Valine, it was first isolated from casein in 1901 by Hermann Emil Fisher. The name valine comes from valeric acid, which in turn is named after the plant valerian due to the presence of the acid in the roots of the plant. Casein, which is present in milk.

This result should be right because Alex does not drink milk or eat any dairy products, not because he is allergic to it or on a casein-free diet, but because he does not like it. (May 2022 – Alex is dairy sensitive, not lactose intolerant, but sensitive to dairy)

Interesting read:  https://www.discovermagazine.com/health/discovered-an-amino-acid-deficiency-that-causes-neurological-problems

Your body needs 20 different amino acids to grow and function properly. While all 20 of these are important for your health, only 9 are classified as essential. 

🌟 The 9 Essential Amino Acids:

  1. Histidine

    • Your body uses this amino acid to produce histamine, a neurotransmitter that is vital to immune response, digestion, sexual function, and sleep-wake cycles. It’s critical for maintaining the myelin sheath, a protective barrier that surrounds your nerve cells.

  2. Isoleucine

    • Isoleucine is involved in muscle metabolism and is heavily concentrated in muscle tissue. It’s also important for immune function, haemoglobin production, and energy regulation.

  3. Leucine

    • Another BCAA, key for muscle protein synthesis, wound healing, and regulating blood sugar.

  4. Lysine

    • Crucial for collagen formation, calcium absorption, and immune support.

    • Like valine, leucine is a BCAA that is critical for protein synthesis and muscle repair. It also helps regulate blood sugar levels, stimulates wound healing, and produces growth hormones.

  5. Methionine

    • Involved in detoxification, methylation (MTHFR pathway), and starting the synthesis of other amino acids like cysteine.

    • It’s also necessary for tissue growth and the absorption of zinc and selenium, minerals that are vital to your health.

  6. Phenylalanine

    • Precursor to tyrosine, dopamine, norepinephrine, and epinephrine (neurotransmitters).

  7. Threonine

    • This is a principal part of structural proteins such as collagen and elastin, which are important components of your skin and connective tissue. It also plays a role in fat metabolism and immune function.

  8. Tryptophan

    • Precursor to serotonin, melatonin, and niacin (vitamin B3). Important for mood, sleep, and stress regulation.

  9. Valine

    • Also a BCAA, helps with muscle repair, energy production, and nitrogen balance.

 

PLEASE NOTE: ANY VIEWS REGARDING THE RESULTS ARE MY UNDERSTANDING AND DO NOT SERVE AS PROFESSIONAL ADVICE. THE TREATMENT RECOMMENDATION IS STRICTLY RELATING TO ALEX’S RESULTS AND IS NOT MEANT FOR SELF-TREATMENT. ALWAYS SPEAK TO YOUR HEALTHCARE PROVIDER BEFORE STARTING ANY TREATMENTS.

Updated 30/029/2023 @ 18:30

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