Food Groups
Ready & Packaged Foods12 ›Vegetables & Legumes12 ›Desserts & Confectionery8 ›Meat & Protein10 ›Grains & Bakery6 ›Beverages6 ›Milk & Dairy4 ›Natural & Other Foods14 ›Categories
Category
Canned & Jarred ProductsBrowse every food in this category.
Canned & Jarred ProductsSee all products →Category
Packaged Breakfast ProductsBrowse every food in this category.
Packaged Breakfast ProductsSee all products →Category
Other Packaged FoodsBrowse every food in this category.
Other Packaged FoodsSee all products →Category
Radishes & BrassicasBrowse every food in this category.
Radishes & BrassicasSee all products →Category
Ice Cream & Frozen DessertsBrowse every food in this category.
Ice Cream & Frozen DessertsSee all products →Category
Puddings & Cream DessertsBrowse every food in this category.
Puddings & Cream DessertsSee all products →Category
Plant Protein & TofuBrowse every food in this category.
Plant Protein & TofuSee all products →Category
Protein Products & PowdersBrowse every food in this category.
Protein Products & PowdersSee all products →Category
Other High-Protein FoodsBrowse every food in this category.
Other High-Protein FoodsSee all products →Category
Bread & Grain BakeryBrowse every food in this category.
Bread & Grain BakerySee all products →Category
Oats & Breakfast CerealsBrowse every food in this category.
Oats & Breakfast CerealsSee all products →Category
Wheat, Flour & BulgurBrowse every food in this category.
Wheat, Flour & BulgurSee all products →Category
Fruit & Vegetable JuicesBrowse every food in this category.
Fruit & Vegetable JuicesSee all products →Category
Water & Mineral WaterBrowse every food in this category.
Water & Mineral WaterSee all products →Category
Energy, Sports, Smoothie & OtherBrowse every food in this category.
Energy, Sports, Smoothie & OtherSee all products →Category
Yoghurt, Kefir & AyranBrowse every food in this category.
Yoghurt, Kefir & AyranSee all products →Category
Butter, Cream & OtherBrowse every food in this category.
Butter, Cream & OtherSee all products →Category
Other / Processed SeafoodBrowse every food in this category.
Other / Processed SeafoodSee all products →Category
Other / Dried FruitsBrowse every food in this category.
Other / Dried FruitsSee all products →Category
Herbs & Spice BlendsBrowse every food in this category.
Herbs & Spice BlendsSee all products →
🧅
Onion slices Calories
Fresh onion slices, low calorie, source of fiber and vitamin C
CALORIES
GI
POTASSIUM
FIBER
Onion slices Nutrition Facts
Selected: 100 g
40
KCAL / 100G
Carbs
9.3g
· 88%
Protein
1.1g
· 10%
Fat
0.1g
· 2%
Fiber
1.7g
Onion slices Vitamins & Minerals
Vitamins
Vitamin C
7.4mg · 8% DV
B6
0.12mg · 7% DV
Folate
19µg · 5% DV
B1
0.05mg · 4% DV
Minerals
Phosphorus
29mg · 4% DV
Potassium ⭐
146mg · 4% DV
Calcium
23mg · 2% DV
Magnesium
10mg · 2% DV
Onion slices Glycemic Index
GLYCEMIC INDEX
GLYCEMIC LOAD
Accounts for portion size — a more realistic measure than GI alone.
Is Onion slices Processed?
NOVA 1
Unprocessed
1. Unprocessed
2. Minimally Processed
3. Processed
4. Ultra-Processed
NOVA classifies foods into 4 groups by industrial processing. NOVA 1 (unprocessed) is the healthiest.
Does Onion slices Contain Allergens?
No known major allergens
Which Diets Is Onion slices Good For?
Vegan
✓ Suitable
Vegetarian
✓ Suitable
Gluten-Free
✓ Suitable
Dairy-Free
— Not suitable
Mediterranean
✓ Suitable
Paleo
✓ Suitable
Whole30
— Not suitable
DASH
— Not suitable
Keto
— Not suitable
Low FODMAP
— Not suitable
Onion slices Fat Profile
SATURATED
0.03g
MONOUNSATURATED
0.01g
POLYUNSATURATED
0.03g
Omega 6:3 ratio 2:1
Below the ideal 4:1 — a good omega balance.
Foods Similar to Onion slices
Onion slices — Frequently Asked Questions
Are onion slices easier to digest raw or cooked?
Cooked onion is often easier to tolerate than raw onion. Raw onion can trigger gas, bloating, or heartburn in sensitive people.
How can I reduce tearing when slicing onions?
Chilling the onion briefly and using a sharp knife can help limit the release of irritating compounds. Leaving the root end until last may also help.
How long do sliced onions keep in the fridge?
Stored in a sealed container or wrapped well, sliced onions usually keep for up to 7 days in the refrigerator. Discard them if they develop slime, off smells, or excessive softness.
Can onion slices be frozen?
Yes, they freeze well for cooking. After thawing, the texture becomes softer, so they are better for soups, sautés, and stews than for fresh salads.
Does frying or sautéing onion destroy its nutrition?
No, it does not destroy everything. Prolonged high heat can reduce some sensitive compounds, but cooking also softens flavor and may make onion easier to eat for some people.
What foods pair well with onion slices?
They work well with beans, eggs, meat, fish, yogurt-based dishes, and salads. Acidic ingredients such as lemon juice or vinegar can balance their sharpness.
Do onions boost immunity on their own?
No single food meaningfully boosts immunity by itself. Onion can be part of a balanced diet, but it is not a cure-all.
Are raw onion slices a good pre-workout food?
Usually not ideal, especially if you are prone to stomach discomfort or burping. Before training, many people do better with simpler, easier-to-digest foods.
Is it bad to eat onions at night?
Not for most people. But if you have reflux, a sensitive stomach, or tend to bloat, raw onion in the evening may be uncomfortable.
Who should be careful with onion slices?
People with IBS, reflux, or a sensitive stomach may react poorly to raw onion. Anyone with known onion intolerance or allergy should avoid it and follow medical advice.
Have another question about Onion slices?
Ask the AI nutrition coach — calories, portions, alternatives and more, answered in seconds in the app.
Scan calories with your camera
Instant AI nutrition analysis
Nutrition data compiled from USDA FoodData Central and scientific sources.