All sweet bell peppers start as green peppers, which are both edible and nutritious at this stage. Depending on the variety, green peppers left on the vine ripen into yellow, red, orange, purple or even brown bell peppers. The three most popular varieties are the milder yellow and red bell peppers, along with the younger, slightly pungent green bell peppers. Their different pigment colors translate into a considerable difference in nutrients. Yellow peppers' claims to fame include their sweet taste and high vitamin C content.
A 100 g serving of fresh yellow peppers, which equals about 2/3 cup of chopped peppers, contains 27 calories and no fat, cholesterol or sodium. The slightly sweet vegetables contain 6 g of carbohydrates. A serving also provides about 1 g each of protein and dietary fiber.
The yellow bell pepper's chief contribution to your meal comes from its vitamin C content. A 2/3-cup serving of yellow bell peppers delivers 184 mg – or 306 percent of the recommended daily value of vitamin C. The vitamin is an antioxidant that bolsters the immune system. Getting proper amounts of vitamin C can help you lower the risk of heart disease and some cancers. The vitamin also builds collagen, an important component of healthy skin and cartilage. Because cooking depletes the vitamin C content of foods, raw or lightly sautéed yellow peppers are the healthiest serving options.
You'll get 8 percent of the vitamin B-6 you need for the day from a 2/3-cup serving of yellow peppers. All of the B-complex vitamins promote healthy liver function, as well as healthy eyes, skin and hair. Foods rich in the B vitamins also help you covert the carbohydrates you eat into energy. Vitamin B-6 is also one of the nutrients responsible for controlling the amino acid homocysteine, high levels of which are believed to be associated with heart disease. Vitamin B-6 also promotes healthy brain function and hormone production, and may help fight morning sickness, premenstrual syndrome and depression.
A serving of yellow bell peppers provides 7 percent of the daily value for folate, a B vitamin. The nutrient is especially important for pregnant women because it supports healthy fetal growth. Like B-6, folate controls homocysteine levels, which may lower your risk for heart disease. It also might alleviate depression in some people and decrease the chances of developing certain cancers.
A 2/3-cup serving of fresh yellow bell peppers contributes at least 2 percent of the vitamin A, thiamin, niacin and vitamin B-5 you need each day. You'll also obtain at least 2 percent of the daily values of iron, magnesium, phosphorus, potassium, copper and manganese.
All popular bell peppers are excellent sources of vitamin C, but yellow peppers are the king for this crucial nutrient. Yellow bell peppers offer three days' worth of the vitamin, compared with the two days' worth that red bell peppers provide and the one day's worth that green peppers deliver. For vitamin A, red peppers are the powerhouse of the group, providing 63 percent of the daily value for vitamin A, compared with 7 percent of the daily value from green peppers and 4 percent from yellow peppers. Red and green peppers have twice the fiber than yellow peppers provide, although yellow peppers are slightly higher in iron. All three peppers have similar mineral content.