Ketchup vs Onion
Side-by-side macro comparison. Ketchup vs Onion per their standard serving sizes.
Macro Comparison Table
| Macro | Ketchup | Onion | Difference |
|---|---|---|---|
| Calories | 17 cal | 44 cal | -61% Ketchup |
| Protein | 0.2g | 1.2g | -83% Ketchup |
| Carbs | 4g | 10g | -60% Ketchup |
| Fat | 0g | 0.1g | -100% Ketchup |
Differences shown relative to Ketchup. Positive = Ketchup has more.
Quick Take
Ketchup delivers 17 calories per serving with 0.2g protein, 4g carbs, and 0g fat. Onion delivers 44 calories with 1.2g protein, 10g carbs, and 0.1g fat. The most meaningful difference: they're within 27 calories per serving, so calorie load is essentially equivalent. Both deliver similar protein density.
When to Pick Each
For Cutting / Weight Loss
When cutting on a tight calorie budget, Ketchup gives you 27 more calories of headroom per serving — that's room for an extra snack, more vegetables, or a higher-protein second portion. If protein density matters more (which it does for preserving muscle on a deficit), Onion delivers more grams of protein per calorie consumed.
For Bulking / Muscle Gain
For muscle gain, you want calories AND protein. Onion brings 44 calories — useful when you're chasing a surplus and struggling to eat enough. Onion delivers 1.2g of protein per serving, which directly feeds muscle protein synthesis. The best pick depends on whether you need more total calories or more usable protein.
For Keto / Low-Carb
Ketchup fits cleanly into keto with only 4g carbs. Onion at 10g carbs uses significantly more of your daily 20g carb budget.
Frequently Asked
Which has more protein, Ketchup or Onion?
Onion has more protein: 1.2g vs 0.2g per serving. That's a difference of 1g.
Which has fewer calories, Ketchup or Onion?
Ketchup has 17 calories per serving vs 44 calories in Onion — a difference of 27 calories.
Is Ketchup or Onion better for keto?
Ketchup is the better keto choice at 4g carbs per serving vs 10g carbs in Onion.
Is Ketchup or Onion better for weight loss?
For weight loss, Ketchup gives you more calorie flexibility (27 cal less per serving). For preserving muscle during a deficit, Onion delivers more protein per calorie. Most people on cuts benefit from Onion.
Which Is Better for Your Goal?
🔥 Weight Loss
Onion
Higher protein-to-calorie density + lower absolute fat = more satiety per calorie.
💪 Muscle Gain
Onion
Higher absolute protein per serving better supports muscle protein synthesis.
🥑 Low-Carb / Keto
Ketchup
Lower carbohydrate content fits keto and low-carb macros without burning your carb budget.
Both fit most balanced diets. These verdicts reflect macro-only comparisons — taste, satiety, cost, and personal preference also matter.
Find Your Personal Macros
The "right" food depends on your individual macro targets. Calculate yours in 60 seconds:
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