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Bell Pepper (red) vs Onion

Calories, macronutrients and nutrition facts compared side by side (per 100g).

Nutrition Comparison

Per 100gBell Pepper (red)Onion
Calories31kcal40kcal
Protein1g1.1g
Carbs6g9.3g
Fat0.3g0.1g
Fiber2.1g1.7g
Sugar4.2g4.2g
Sodium4mg4mg

Green marks the more favorable value (fewer calories/sugar/sodium, more protein/fiber).

Key Takeaways

  • Bell Pepper (red) has 9 fewer calories per 100g than Onion (29% less).
  • Onion delivers more protein (1.1g vs 1g per 100g).
  • Bell Pepper (red) has more fiber (2.1g vs 1.7g).
  • Onion contains less fat (0.1g vs 0.3g).

Bell Pepper (red)

Red bell peppers contain nearly three times more vitamin C than oranges and are loaded with vitamin A precursors. They also provide vitamin B6, folate, and capsanthin — a powerful carotenoid responsible for the red color and linked to antioxidant activity.

View Bell Pepper (red) nutrition →

Onion

Onions are low in calories and a notable source of quercetin, an antioxidant flavonoid, plus prebiotic fibers that feed gut bacteria. Their sulfur compounds — released when chopped — are being studied for cardiovascular benefits.

View Onion nutrition →

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