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Raw onion Calories
Raw onion
In season: Spring · Summer · Autumn · Winter
CALORIES
GI
POTASSIUM
FIBER
Quick answer
1 piece (medium) of Raw onion (80 g) has 32 calories. That works out to 40 calories per 100 g. It contains 7.4 g of carbs, 0.9 g of protein, 0.1 g of fat and 1.4 g of fiber. Its 5.9 mg of Vitamin C covers 7% of the Daily Value. Its glycemic index is 15 (low), so it raises blood sugar slowly.
What is Raw onion?
Raw onion is simply a peeled onion served uncooked, often cut into rings, wedges or thin slices. Its crisp bite and pungent, lightly sweet flavour bring freshness and contrast to meals. Around the world, it is added to salads, sandwiches, burgers and salsas, or served alongside grilled meats and other savoury dishes; lemon or vinegar can soften its sharp edge.
It is very low in fat and provides some carbohydrate and fibre; 100 g contains 40 calories. If you prefer a milder taste, rinse or briefly soak the slices in cold water, then drain them before serving.
Raw onion Nutrition Facts
Selected: 100 g
40
KCAL / 100G
Carbs
9.3g
· 3% DV
Protein
1.1g
· 2% DV
Fat
0.1g
· 0% DV
Fiber
1.7g
· 6% DV
DV is the share of the daily value covered, on a 2,000 kcal reference diet.
Calories come from: Carbs 88% · Protein 10% · Fat 2%
Raw onion 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
How Nutritious Is Raw onion?
Nutrient density
High
How many vitamins, minerals and how much fiber this food carries per calorie. A high score means a lot of nutrition for few calories.
Satiety score
Medium
An EatBetter score computed from fiber, protein and calorie density. A high score means staying full longer on the same calories.
Both scores are calculated per 100 g and do not change with the selected portion. The satiety score is EatBetter's own calculation, not a clinical measure.
Raw onion Glycemic Index
GLYCEMIC INDEX
GLYCEMIC LOAD
Accounts for portion size — a more realistic measure than GI alone.
How to Burn Off Raw onion
To burn the 40 calories in 100 g:
🚶
Walking (5 km/h)
🏃
Running (8 km/h)
🚴
Cycling
🏊
Swimming
Times are calculated with the MET equation for a 70 kg adult. Actual burn varies with your weight, age and pace.
Is Raw onion 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 Raw onion Contain Allergens?
No known major allergens
Which Diets Is Raw onion 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
Raw onion Fat Profile
SATURATED
0.03g
MONOUNSATURATED
0.01g
POLYUNSATURATED
0.02g
Omega 6:3 ratio 2:1
Below the ideal 4:1 — a good omega balance.
Compare Raw onion
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Frequently Asked Questions About Raw onion
Is raw onion good for you?
Yes, raw onion can be part of a healthy diet and provides plant compounds, including quercetin. It also contains fermentable carbohydrates that can bother some people, so those prone to bloating may find cooked onion easier to tolerate.
How do you stop raw onion from tasting so strong?
Soak thinly sliced raw onion in cold water for a few minutes, then drain it well. This reduces some of its sharp bite while keeping it crisp; a squeeze of lemon or vinegar can also balance the flavor.
Why does raw onion make you cry when you cut it?
Cutting raw onion releases volatile sulfur compounds that irritate the eyes. Chilling the onion beforehand, using a sharp knife, and cutting near good ventilation can reduce the amount of irritation.
How long does cut raw onion last in the fridge?
Store cut raw onion in a sealed container in the refrigerator and use it within a few days for the best quality. Discard it if it develops an unusual smell, slimy surface, or other signs of spoilage.
Can you freeze raw onion?
Yes, raw onion can be frozen, preferably chopped or sliced in an airtight freezer bag. It will soften after thawing, so use it in cooked dishes such as soups and sauces rather than expecting crisp slices for salads.
Does raw onion cause gas or bloating?
Yes, raw onion can cause gas or bloating in some people because it contains fermentable carbohydrates. If it bothers you, try a smaller amount or cooked onion, which many people find easier to digest.
Which onion is best to eat raw?
Sweet onions and red onions are often popular raw because their flavor can be milder than that of yellow onions. Choose a firm bulb without soft spots, and taste a small slice before adding it to a dish.
Can you eat raw onion every day?
Yes, most people can include raw onion regularly as part of meals. Its strong flavor and fermentable carbohydrates may cause discomfort for some, so adjust the amount if it triggers bloating or heartburn.
Does raw onion cause bad breath?
Yes, raw onion can cause temporary bad breath because its sulfur compounds can linger in the mouth and breath. Drinking water and brushing your teeth and tongue after eating can help reduce the odor.
Should you wash raw onion before cutting it?
Yes, rinse the whole onion under running water before peeling and cutting it, then dry it with a clean towel. Washing first helps prevent dirt on the outer skin from being transferred to the edible layers by the knife.
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Nutrition data compiled from USDA FoodData Central and scientific sources.