Fresh, raw bell peppers are mainly composed of water (92%). The rest is carbs and small amounts of protein and fat.

The main nutrients in 3.5 ounces (100 grams)Trusted Source of raw, red bell peppers are:

• Calories: 31
• Water: 92%
• Protein: 1 gram
• Carbs: 6 grams
• Sugar: 4.2 grams
• Fiber: 2.1 grams
• Fat: 0.3 grams

Carbs

Bell peppers are primarily composed of carbs, which account for most of their calorie content — with 3.5 ounces (100 grams) holding 6 grams of carbs.

The carbs are mostly sugars — such as glucose and fructose — which are responsible for the sweet taste of ripe bell peppers.

Bell peppers also contain small amounts of fiber — 2% by fresh weightTrusted Source. Calorie for calorie, they are a very good fiber source.

SUMMARYBell peppers are mainly made up of water and carbs. Most of the carbs are sugars, such as glucose and fructose. Bell peppers are also a decent source of fiber.

Bell peppers are loaded with various vitamins and mineralsTrusted Source:

• Vitamin C. One medium-sized red bell pepper provides 169% of the Reference Daily Intake (RDI) for vitamin C, making it one of the richest dietary sources of this essential nutrient.
• Vitamin B6. Pyridoxine is the most common type of vitamin B6, which is a family of nutrients important for the formation of red blood cells.
• Vitamin K1. A form of vitamin K, also known as phylloquinone, K1 is important for blood clotting and bone health.
• Potassium. This essential mineral may improve heart healthTrusted Source.
• Folate. Also known as vitamin B9, folate has a variety of functions in your body. Adequate folate intake is very important during pregnancyTrusted Source.
• Vitamin E. A powerful antioxidant, vitamin E is essential for healthy nerves and muscles. The best dietary sources of this fat-soluble vitamin are oils, nuts, seeds, and vegetables.
• Vitamin A. Red bell peppers are high in pro-vitamin A (beta carotene)Trusted Source, which your body converts into vitamin A.

SUMMARYBell peppers are very high in vitamin C, with a single one providing up to 169% of the RDI. Other vitamins and minerals in bell peppers include vitamin K1, vitamin E, vitamin A, folate, and potassium.

Bell peppers are rich in various antioxidants — especially carotenoids, which are much more abundant in ripe specimens.

The main compounds in bell peppers are:

• Capsanthin. Especially high in red bell peppersTrusted Source, capsanthin is a powerful antioxidant responsible for their brilliant red color.
• Violaxanthin. This compound is the most common carotenoid antioxidant in yellow bell peppers (8Trusted Source).
• Lutein. While abundant in green (unripe) bell peppers and black paprika, lutein is absent from ripe bell peppers. Adequate intake of lutein may improve eye healthTrusted Source.
• Quercetin. Studies indicate that this polyphenol antioxidant may be beneficial for preventing certain chronic conditionsTrusted Source, such as heart disease and cancer.
• Luteolin. Similarly to quercetin, luteolin is a polyphenol antioxidant that may have a variety of beneficial health effects Source.

SUMMARYBell peppers contain many healthy antioxidants, including capsanthin, violaxanthin, lutein, quercetin, and luteolin. These plant compounds are associated with many health benefits.

Like most whole plant foods, bell peppers are considered a healthy food.

High consumption of fruits and vegetables has been linked to a reduced risk of many chronic illnesses, such as cancer and heart disease.

In addition, bell peppers may have several other health benefits.

Eye Health

The most common types of visual impairments include macular degenerationTrusted Source and cataracts, the main causes of which are aging and infections.

However, nutrition may also play a significant role in developing these diseases.

Lutein and zeaxanthinTrusted Source — carotenoids found in relatively high amounts in bell peppers — may improve eye health when consumed in adequate amounts.

They protect your retinaTrusted Source — the light-sensitive inner wall of your eye — from oxidative damage.

Several studies indicate that regular consumption of foods rich in these carotenoids may cut the risk of both cataracts and macular degenerationTrusted Source.

Thus, adding bell peppers to your diet may help lower your risk of visual impairments.

Anemia prevention

Anemia is a common condition characterized by a reduced ability of your blood to carry oxygen.

One of the most common causes of anemia is iron deficiency, the main symptoms of which are weakness and tiredness.

Not only are red bell peppers a decent source of iron, they are also exceptionally rich in vitamin C, which increases the absorption of iron from your gutTrusted Source.

One medium-sized red bell pepper may contain 169% of the RDI for vitamin CTrusted Source.

Dietary iron absorption increases significantly when you consume fruits or vegetablesTrusted Source high in vitamin C.

For this reason, eating raw bell peppers alongside iron-rich foods — such as meat or spinach — may help increase your body’s iron stores, cutting your risk of anemia.

SUMMARYLike other fruits and vegetables, bell peppers may have many health benefits. These include improved eye health and reduced risk of anemia.

Bell peppers are generally healthy and well-tolerated, but some people may be allergic. That said, allergy is quite rare.

Still, some people who have pollen allergy may also be sensitive to bell peppers due to allergic cross-reactivity (26Trusted Source, 27Trusted Source).

Allergic cross-reactions can happen between certain foods because they may contain the same allergens — or allergens similar in chemical structure.

SUMMARYWhen eaten in moderation, bell peppers do not have any adverse health effects. However, they may trigger allergies in some people.

Source: Bell Peppers 101: Nutrition Facts and Health Benefits (healthline.com)