Avocado and banana are both routinely described as potassium-rich foods, but a fair comparison needs one more detail: are you comparing equal weights or the amount people normally eat?
Per 100 grams
| Nutrient | Raw avocado | Raw banana |
|---|---|---|
| Calories | ~160 | ~89 |
| Potassium | ~485 mg | ~358 mg |
| Fiber | ~6.7 g | ~2.6 g |
| Carbohydrate | ~8.5 g | ~22.8 g |
| Fat | ~14.7 g | ~0.3 g |
| Protein | ~2.0 g | ~1.1 g |
At equal weight, avocado provides about 127 mg more potassium and roughly 4.1 g more fiber. It also provides about 71 more calories, largely because avocado contains much more fat.
A medium banana can still provide more potassium than half an avocado
Half an avocado with about 75 g edible portion provides roughly 120 calories, 5 g fiber, and 364 mg potassium. A medium banana at about 118 g provides around 105 calories, 3.1 g fiber, and 422 mg potassium.
So both statements can be true: avocado is more potassium-dense per 100 g, while a medium banana supplies about 58 mg more potassium than half an avocado because the banana serving weighs more.
The calorie difference comes from different macros
Banana gets most of its energy from carbohydrate. Avocado is rich in fat, particularly monounsaturated fat. That is why 100 g of avocado is roughly 160 calories versus about 89 calories for banana.
This does not make one fruit universally better for weight management. It means equal gram weights have different energy density and real serving size matters.
Avocado has a clear fiber advantage
At 6.7 g versus 2.6 g per 100 g, avocado contains about 2.6 times as much fiber by weight. The difference remains meaningful at typical servings: roughly 5 g in half an avocado versus about 3.1 g in a medium banana.
What about sugar and carbs?
Banana contains considerably more digestible carbohydrate and natural sugars, while avocado contains very little sugar and much more fat. Total carbohydrate is about 22.8 g/100 g in banana versus 8.5 g/100 g in avocado, with a large share of avocado carbohydrate coming from fiber.
The better choice depends on what job the food needs to do. A banana is mostly carbohydrate and water, so it works naturally as a quick snack before activity or as a sweet component in breakfast. Avocado gets much more of its energy from unsaturated fat and carries substantially more fiber per 100 grams. That makes it slower, richer, and more useful when the goal is adding satiety or replacing a fatty spread rather than providing fast carbohydrate.
Portion size can reverse the impression created by a 100-gram table. A typical banana may weigh well over 100 grams of edible fruit, whereas half an avocado may be smaller or larger depending on the variety. Looking at what you actually eat is more informative than assuming identical weights. The same applies to potassium: both contribute, but neither has to be treated as a supplement-like source when a varied diet includes potatoes, beans, leafy greens, dairy, fish, and other potassium-rich foods.
They also pair differently with a meal. Banana adds sweetness and carbohydrate to yogurt, oats, or a smoothie. Avocado adds creaminess, fat, and fiber to toast, salads, beans, eggs, or grain bowls. Choosing between them purely on calories misses those roles; the useful comparison is which profile complements the rest of the meal.
If weight management is the concern, neither fruit needs to be avoided. The avocado is more calorie-dense, but its fat and fiber can make a modest portion satisfying. The banana is lower in calories per gram and usually easier to eat as a whole portable snack. Problems arise more from portion creep and additions than from the foods themselves: a smoothie with multiple bananas, sweetened yogurt, nut butter, and juice can become energy-dense, just as avocado toast can become much richer when covered with oil, cheese, or several slices of bread.
Ripeness also changes texture and perceived sweetness. A greenish banana contains more resistant starch and tastes less sweet; as it ripens, starch is converted into sugars. Avocado ripening mainly softens the flesh and develops flavor rather than turning it into a sugary fruit. That difference explains why banana works naturally in sweet recipes while avocado is commonly used in savory meals, even though both are botanically fruits and both contribute potassium.
The practical takeaway
Per 100 g, avocado has more potassium and substantially more fiber; banana has fewer calories and more carbohydrate. In ordinary servings, a medium banana can beat half an avocado for total potassium. Use the comparison that matches what is actually on the plate.
Sources
- USDA FoodData Central — Raw avocado and banana nutrient composition per 100 g and edible serving weights.