The onion is a vegetable that not only gives dishes a distinctive flavor and aroma but also provides the body with valuable nutrients. It’s widely available and commonly used in cooking, but do we really know which vitamins and minerals are hidden inside this humble vegetable? In this post, we’ll take a closer look at raw onions, explore their many uses, and uncover the nutritional value they contain.

An Irreplaceable Ingredient for Generations

The onion (Allium cepa) is a popular vegetable from the Allium family. There are many different varieties that differ in shape, color, flavor, and culinary use. Each type has its unique characteristics, making onions one of the most versatile and beloved ingredients in cuisines around the world.

Yellow onions are the most common variety, known for their mildly sharp taste. They can be eaten raw, boiled, or fried. While all forms are flavorful, raw yellow onions contain the highest level of nutrients. White onions have a milder flavor, while red onions are known for their deep, purplish-red skin. Regardless of variety, onions remain one of the most essential vegetables in every kitchen.

Their presence in culinary traditions dates back hundreds or even thousands of years. This remarkable vegetable has truly stood the test of time, becoming a key ingredient in traditional recipes passed down from generation to generation.

What Vitamins Does Onion Contain?

When discussing the vitamins found in onions, it’s worth noting that they are rich in various nutrients. Many of these vitamins are concentrated in the skin and outer layers, so eating onions raw or only lightly sautéed helps preserve their full nutritional value. Interestingly, onion juice has long been used in folk medicine as a remedy for colds, coughs, and even to improve skin health.

Vitamin C

Raw onions are an excellent source of vitamin C, a powerful antioxidant that supports the immune system and aids in collagen production. It’s especially concentrated in the outer layers of the onion, but is also present throughout the entire bulb. To retain as much vitamin C as possible, onions should undergo minimal heat processing. When it comes to which vitamin onions contain the most, the answer is clearly vitamin C.

B-Group Vitamins

Onions also provide several B vitamins, including B6, B9 (folic acid), B3 (niacin), B5 (pantothenic acid), and B2 (riboflavin). Vitamin B6 plays a crucial role in amino acid and carbohydrate metabolism, affecting the nervous system’s function. Raw onions supply folic acid, essential for DNA synthesis and red blood cell production. It’s particularly important for pregnant women as it helps prevent neural tube defects in the fetus. Niacin supports energy metabolism, while pantothenic acid helps regulate the conversion of carbohydrates, proteins, and fats. Riboflavin contributes to maintaining healthy skin and hair.

Vitamin K

Vitamin K is fat-soluble and plays a key role in blood clotting. It contributes to the production of plasma coagulation factors and the protein prothrombin. A deficiency in these components can impair the blood clotting process. Although onions contain only a small amount of vitamin K, it still contributes beneficially to a balanced diet.

Minerals

In addition to vitamins, raw onions are also a valuable source of minerals. They contain significant amounts of potassium, which supports proper muscle function — including the heart — and helps regulate blood pressure. Onions also provide magnesium, which regulates enzyme activity and influences calcium and vitamin D metabolism. Moreover, they are a source of manganese, an essential cofactor for many enzymes that aid in nutrient metabolism and act as antioxidants.

Raw Onion – a Treasure of Flavor and Health

The onion is undeniably a nutritious and flavorful addition to many dishes, providing valuable nutrients — especially vitamin C. However, it may not be suitable for everyone. People with certain health issues such as kidney, intestinal, or liver diseases should consume it with caution. In such cases, it’s advisable to consult a doctor or dietitian to find alternative vitamin sources or adjust onion intake appropriately.