A nutrient-dense aromatic vegetable rich in the flavonoid antioxidant quercetin, organosulfur compounds, and prebiotic fructans that support cardiovascular wellness and digestive health (USDA, NIH ODS, Harvard Nutrition Source).
Supports
Supports Cardiovascular FunctionNourishes Gut MicrobiotaProvides Cellular Antioxidant Defense
Practical guidance grounded in general dietary advice (EFSA / WHO / NHS) — not personal medical advice.
Who benefits most
Who Onion is especially good for
When to be careful
Be careful with Onion if…
Balanced advice — real cautions, not scaremongering.
Why it's healthy
Why eat Onion?
How it works in the body
The mechanisms behind Onion
Not just what's inside — what each nutrient actually does once you eat it.
Body systems
How Onion maps to body functions
Health benefit
Supports Cardiovascular Function
Onions provide quercetin and sulfur-containing compounds, which are associated with reduced vascular inflammation and support for healthy blood pressure levels when consumed as part of a vegetable-rich diet (PubMed, Harvard Nutrition Source).
Health benefit
Nourishes Gut Microbiota
Contains soluble prebiotic fibers, specifically fructans and inulin, which selectively feed beneficial gut bacteria and help support digestive barrier integrity (NIH ODS, Harvard Nutrition Source).
Health benefit
Provides Cellular Antioxidant Defense
Supplies polyphenols and vitamin C that contribute to neutralizing reactive oxygen species and protecting cellular structures from oxidative damage (USDA, NIH ODS).
Nutrition breakdown
What's actually in a serving
Percentages show how much of an adult's daily need one serving covers. Adjust the amount to match your plate.
Choose a serving
g
Typical serving: 100 g ≈ 100 g
Bars compare each nutrient to a general adult daily reference value (EFSA / NIH). Individual needs vary.
Per 100 g serving
Calories40kcal
Protein1.1g
Carbohydrates9.3g
Fat0.1g
Fibre1.7g
Sodium4mg
Vitamins
Folate19.0µg
Choline6.1mg
Vitamin C7.4mg
Vitamin E0.0mg
Vitamin K0.4µg
Vitamin B10.1mg
Vitamin B20.0mg
Vitamin B30.1mg
Vitamin B50.1mg
Vitamin B60.1mg
Minerals
Iron0.2mg
Zinc0.2mg
Copper0.0mg
Calcium23.0mg
Selenium0.5µg
Magnesium10.0mg
Manganese0.1mg
Potassium146.0mg
Phosphorus29.0mg
Show raw per-100 g values
Calories40kcal
Protein1.1g
Carbohydrates9.34g
of which sugars4.24g
Fat0.1g
of which saturates0.04g
Fibre1.7g
Sodium4mg
Works well with
Best pairings & ingredient synergies
Combinations where the whole is nutritionally greater than the sum of its parts.
On the plate
Recipes featuring Onion
More recipes featuring Onion are coming soon.
Did you know?
Small facts that change how you look at it
AI-assisted educational summary. Cross-check with the sources below for clinical decisions.
Preparation & storage
Getting the most out of it
Sauté slowly until sweet and golden.
Slice thin and pickle for a tangy topping.
Add raw to salads and salsas.
Things to consider
Context matters
Rich in fermentable oligosaccharides (fructans), which may trigger gas, bloating, or abdominal discomfort in individuals sensitive to FODMAPs or diagnosed with irritable bowel syndrome (IBS) (Harvard Nutrition Source).
Inside Food only draws on these six sources — USDA for nutrient composition, EFSA, NIH ODS, WHO and PubMed for scientific evidence, and the Harvard T.H. Chan Nutrition Source for practical synthesis. Anything on this page not confirmed in one of them is marked with a red Unverifiedbadge.
This platform provides general nutrition information and is not a substitute for medical advice, diagnosis, or treatment. Nutritional needs vary between individuals.
