Onions, just like garlic, are members of the Liliaceae plant family. After broccoli, Brussels sprouts, shallots and celery, onion is one of the richest sources of polyphenols. These are one of the best types of phytonutrients and include both tannins (as found in red wine), and flavonoids, which are great at protecting against many unhealthy strands of bacteria. As well as their natural antibiotic powers, onions are thought to help prevent certain cancers and lower the risk of diabetes and neurodegenerative disorders, such as Alzheimer's and Parkinson's disease. They also help protect the heart, help maintain strong bones, and at the same time lower the risk of arthritis and asthma.

A rich source of: vitamin B6, manganese, folate, potassium, vitamin B1.


Onions, raw

Energy (kcal) 35
Energy (kJ) 150
Water (g) 89.1
Starch (g) 0
Total sugars (g) 6.2
Glucose (g) 2.3
Galactose (g) 0
Fructose (g) 1.8
Sucrose (g) 2.1
Maltose (g) 0
Lactose (g) 0
Protein (g) 1
Protein (g)/100kcal 2.9
Protein % of calories 11.4
Carbohydrate (g) 8
Carbohydrate (g)/100kcal 22.9
Carb % of calories 91.4
Fat (g) 0.1
Fat (g)/100kcal 0.3
Fat % of calories 2.6
Satd FA /100g fd (g) 0
Mono FA /100g food (g) 0
Poly FA /100g food (g) 0.1
Trans FAs /100g food (g) 0
Sodium (mg) 68
Potassium (mg) 340
Calcium (mg) 5
Magnesium (mg) 25
Phosphorus (mg) 220
Iron (mg) 0.6
Copper (mg) 0
Zinc (mg) 1.9
Chloride (mg) 54
Manganese (mg) 0
Selenium (µg) 13
Iodine (µg) 6
Vitamin D (µg) 0.3
Vitamin E (mg) 0
Thiamin (mg) 0.1
Riboflavin (mg) 0.2
Niacin (mg) 8
Tryptophan/60 (mg) 4.4
Niacin equivalent (mg) 12.4
Vitamin B6 (mg) 0.6
Vitamin B12 (µg) 2
Folate (µg) 17
Pantothenate (mg) 0.7
Biotin (µg) 2
Vitamin C (mg) 0
Alcohol (g) 0
NSP (g) Non-starch polysaccharide 1.1
AOAC fibre (g) 2.2
Cholesterol (mg) 0
Retinol (µg) 0
Carotene (µg) 0
Retinol Equivalent (µg) 0

Onions, dried, raw

Energy (kcal) 309
Energy (kJ) 1317
Water (g) 4.5
Starch (g) 0
Total sugars (g) 54.4
Glucose (g) 20.2
Galactose (g) 0
Fructose (g) 15.8
Sucrose (g) 18.4
Maltose (g) 0
Lactose (g) 0
Protein (g) 8.8
Protein (g)/100kcal 2.9
Protein % of calories 11.4
Carbohydrate (g) 70.2
Carbohydrate (g)/100kcal 22.7
Carb % of calories 90.9
Fat (g) 1.2
Fat (g)/100kcal 0.4
Fat % of calories 3.5
Satd FA /100g fd (g) N
Mono FA /100g food (g) N
Poly FA /100g food (g) 0.6
Trans FAs /100g food (g) 0
Sodium (mg) 73
Potassium (mg) 370
Calcium (mg) 6
Magnesium (mg) 23
Phosphorus (mg) 210
Iron (mg) 0.9
Copper (mg) 0.1
Zinc (mg) 2.6
Chloride (mg) 49
Manganese (mg) 0
Selenium (µg) 13
Iodine (µg) N
Vitamin D (µg) 0.5
Vitamin E (mg) 0.3
Thiamin (mg) 1
Riboflavin (mg) 0.3
Niacin (mg) 7.8
Tryptophan/60 (mg) 4.4
Niacin equivalent (mg) 12.2
Vitamin B6 (mg) 0.5
Vitamin B12 (µg) 0.5
Folate (µg) 3
Pantothenate (mg) 1.5
Biotin (µg) 2
Vitamin C (mg) 0
Alcohol (g) 0
NSP (g) Non-starch polysaccharide 9.6
AOAC fibre (g) 19.3
Cholesterol (mg) 0
Retinol (µg) 0
Carotene (µg) 0
Retinol Equivalent (µg) 0