Onions

Overview

Onions provide inulin (prebiotic fiber), quercetin (polyphenol), and sulfur compounds that support gut microbiome, antioxidant defenses, and glutathione synthesis. Prebiotic Fibres: Inulin (chicory, onions), GOS (legumes), resistant starch (cooled potatoes, green bananas), pectin (apples). Inulin (chicory, onions) supports Bifidobacterium, Akkermansia; ↑ butyrate production; improved gut barrier. Quercetin is abundant in capers, apples, onions, berries, kale and soybeans.

Recipes

3 recipes containing this food

Black Bean & Sweet Potato Vegetable Chilli

A fibre-rich bean and vegetable chilli with warming spices and slow carbohydrates for steady energy and satiety.

Linguine con le Cozze Mantecate (Linguine with cockles in a silky emulsified sauce)

Whole-wheat linguine with cockles in a silky emulsified sauce; Italian emulsification technique without cream, supporting taurine, B12, and choline intake.

Turkey Wing Stew

A collagen-rich, glycine-heavy slow-cooked stew made from affordable turkey wings — rich in protein, tryptophan, and B vitamins.

Substances

3 substances in this food

Butyrate

Key SCFA supporting mitochondrial function, gut barrier integrity, and neuroinflammation reduction

Quercetin (and Isoquercetin)

Polyphenol; antioxidant; mitochondrial support; bioavailability improved with vitamin C

Vitamin C (Ascorbate)

Antioxidant; supports iron absorption; neuronal SVCT2 transport

Preparation Notes

• Can be consumed raw or cooked; cooking may enhance some compounds
• Part of diverse prebiotic fiber strategy; prebiotic fibres including inulin (chicory, onions) support Bifidobacterium, Akkermansia; ↑ butyrate production; improved gut barrier
• Pair with other allium vegetables for synergistic effects
• Sulphur-containing vegetables that provide glutathione precursors (e.g., broccoli, Brussels sprouts, garlic, onions) support antioxidant defenses

Biological Target Matrix

Biological Target	Substance	Contribution Level	Therapeutic Areas	Mechanism of Action
Gut–Brain Axis & Enteric Nervous System (ENS)	Butyrate	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base	Byproduct of fibre fermentation; supports intestinal barrier integrity; regulates immune responses; promotes synthesis of key neurotransmitters such as dopamine and serotonin
Inflammation & Oxidative Stress	Butyrate	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Has anti-inflammatory effects, potentially reducing neuroinflammation; deficiencies linked to many neurological disorders including ADHD
Inflammation & Oxidative Stress	Quercetin (and Isoquercetin)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Anti-inflammatory, anti-neuroinflammatory, and neuroprotective properties; supports gut barrier integrity and TLR4 suppression
Inflammation & Oxidative Stress	Vitamin C (Ascorbate)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Antioxidant properties; supports anti-inflammatory effects
Metabolic & Neuroendocrine Stress (HPA Axis & ANS)	Quercetin (and Isoquercetin)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base	Contributes to LPS and immune defense; supports stress response modulation
Metabolic & Neuroendocrine Stress (HPA Axis & ANS)	Vitamin C (Ascorbate)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base	Supports stress response through antioxidant and neurochemical effects
Mitochondrial Function & Bioenergetics	Butyrate	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Supports mitochondrial function, enhancing brain energy metabolism; aids in reducing cholesterol and neuroinflammation
Mitochondrial Function & Bioenergetics	Quercetin (and Isoquercetin)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Enhances mitochondrial baseline activity and energy production; supports mitochondrial function
Neurotransmitter Regulation	Vitamin C (Ascorbate)	Contextual / minor contributor	ADHD, Anxiety & GAD, Depression & MDD, Postnatal Depression (PND / PPD) — Evidence Base, Alzheimer's Disease, Bipolar Disorder	Supports norepinephrine synthesis; transported in brain via SVCT2

References

• Prebiotic Fibres: Inulin (chicory, onions), GOS (legumes), resistant starch (cooled potatoes, green bananas), pectin (apples)
• Sulphur-containing vegetables that provide glutathione precursors (e.g., broccoli, Brussels sprouts, garlic, onions)
• Quercetin is abundant in capers, apples, onions, berries, kale and soybeans
• Inulin (chicory, onions) supports Bifidobacterium, Akkermansia; ↑ butyrate production; improved gut barrier
• Prebiotic fibres including inulin (chicory, onions) support Bifidobacterium, Akkermansia; ↑ butyrate production; improved gut barrier