Summary:
                    
A complete protein is a protein source that "contains adequate proportions of the nine essential amino acids" that our body can not produce on its own.
                      Relatively low in protein, a single banana contains 1.3 grams of protein, or about 3% of recommended daily values. [1]
 To get the adequate amount of protein with banana alone, you will need 39 banana (4590 grams) for an average female, or 47 banana for males. [4] That's over 4080 calories, and a lot of banana! Pairing banana with a richer protein source is a good idea.
                      
                      
                        Full nutritional profile for banana 
                        
                        USDA Source: Bananas, raw
                    
Macronutrients in 1 medium (118g) of banana:
| % of RDV | Amount | ||
| Calories | 
                               | 
                            5.3% | 105 kCal | 
| Carbohydrates | 
                               | 
                            0% | - | 
| Total fat | 
                               | 
                            0.6% | 0.4 grams | 
| Protein | 
                               | 
                            2.6% | 1.3 grams | 
                    Proportionally, banana does contain abundant amounts of 7 out of the nine essential amino acids.  However, banana is a little short on isoleucine and methionine.[1]
To have adequate amounts of all nine essential amino acids with banana alone, you will have to eat 91 banana (10750 grams) for an average person. [2]
That's about 134% more banana to compensate for the lack of isoleucine and methionine, compared to the protein requirement alone.
                  
The amount of each essential amino acid in 1 medium (118g) of banana:
| Amino Acid | % of RDV [2] | Amount [1] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                           
                            2.6% | 1.286g | |
| Histidine | 
                               | 
                           
                            14.4% | 0.091g | |
| Isoleucine | 
                               | 
                           
                            3.8% | 0.033g | |
| Leucine | 
                               | 
                           
                            4.2% | 0.08g | |
| Lysine | 
                               | 
                           
                            3.5% | 0.059g | |
| Methionine | 
                               | 
                           
                            1.1% | 0.009g | |
| Phenylalanine | 
                               | 
                           
                            3.9% | 0.058g | |
| Threonine | 
                               | 
                           
                            3.7% | 0.033g | |
| Tryptophan | 
                               | 
                           
                            4.1% | 0.011g | |
| Valine | 
                               | 
                           
                            5.1% | 0.055g | 
                          
                      
                                              
                          
                          
                                              
                      Low in protein, carrot is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 0.9 banana (107g) and 2.8 carrots (200g) creates a complete protein profile. In fact, any ratio of more than 1.9:1 of carrot to banana will be complete. 
                      
                      
                        Full nutritional profile for carrots 
                        USDA Source: Carrots, raw
                    
| Amino Acid | % of RDV [2] | Amount [5] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            6.1% | 3g | |
| Histidine | 
                               | 
                            25.8% | 0.16g | |
| Isoleucine | 
                               | 
                            21.4% | 0.18g | |
| Leucine | 
                               | 
                            14.7% | 0.28g | |
| Lysine | 
                               | 
                            14.9% | 0.26g | |
| Methionine | 
                               | 
                            5.6% | 0.05g | |
| Phenylalanine | 
                               | 
                            11.7% | 0.17g | |
| Threonine | 
                               | 
                            45.8% | 0.41g | |
| Tryptophan | 
                               | 
                            12.9% | 0.03g | |
| Valine | 
                               | 
                            17.4% | 0.19g | 
                          
                          
                                              
                      Chia seed is a reasonable source of supplementary protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2.5 banana (295g) and 0.3 ounce of chia seeds (9g) make a complete amino acids profile. The entire range to create a complete protein are ratios of 1:0.03 to 1:12 for banana to chia seed by weight. 
                      
                      
                        Full nutritional profile for chia seeds 
                        USDA Source: Seeds, chia seeds, dried
                    
| Amino Acid | % of RDV [2] | Amount [6] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            9.3% | 4.7g | |
| Histidine | 
                               | 
                            43.4% | 0.27g | |
| Isoleucine | 
                               | 
                            17.7% | 0.15g | |
| Leucine | 
                               | 
                            16.9% | 0.32g | |
| Lysine | 
                               | 
                            13.5% | 0.23g | |
| Methionine | 
                               | 
                            8.7% | 0.07g | |
| Phenylalanine | 
                               | 
                            15.6% | 0.23g | |
| Threonine | 
                               | 
                            16% | 0.14g | |
| Tryptophan | 
                               | 
                            24.8% | 0.06g | |
| Valine | 
                               | 
                            20.5% | 0.22g | 
                          
                      
                                              
                          
                          
                                              
                      A reasonable source of supplementary protein, hedge mustard seed is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 2.5 banana (295g) and 0.3 cup of hedge mustard seeds (24g) creates a complete protein profile. The entire range to create a complete protein are ratios of 1:0.08 to 1:33 for banana to hedge mustard seed by weight. 
                      
                      
                        Full nutritional profile for hedge mustard seeds 
                        USDA Source: Seeds, sisymbrium sp. seeds, whole, dried
                    
| Amino Acid | % of RDV [2] | Amount [7] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            12.3% | 6.1g | |
| Histidine | 
                               | 
                            48.5% | 0.31g | |
| Isoleucine | 
                               | 
                            27.8% | 0.24g | |
| Leucine | 
                               | 
                            26.4% | 0.5g | |
| Lysine | 
                               | 
                            20% | 0.34g | |
| Methionine | 
                               | 
                            11.5% | 0.1g | |
| Phenylalanine | 
                               | 
                            19.2% | 0.29g | |
| Threonine | 
                               | 
                            27.7% | 0.25g | |
| Tryptophan | 
                               | 
                            34.9% | 0.09g | |
| Valine | 
                               | 
                            28.6% | 0.31g | 
                          
                      
                                              
                          
                          
                                              
                      Spirulina is a great source of protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2 banana (236g) and 1.4 tablespoons of spirulina (10g) make a complete amino acids profile. The entire range to create a complete protein are ratios of 1:0.04 to 1:21 for banana to spirulina by weight. 
                      
                      
                        Full nutritional profile for spirulina 
                        USDA Source: Seaweed, spirulina, dried
                    
| Amino Acid | % of RDV [2] | Amount [8] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            16.4% | 8.2g | |
| Histidine | 
                               | 
                            45.7% | 0.29g | |
| Isoleucine | 
                               | 
                            44.2% | 0.38g | |
| Leucine | 
                               | 
                            34.1% | 0.64g | |
| Lysine | 
                               | 
                            24.2% | 0.41g | |
| Methionine | 
                               | 
                            15.3% | 0.13g | |
| Phenylalanine | 
                               | 
                            26% | 0.39g | |
| Threonine | 
                               | 
                            39.7% | 0.36g | |
| Tryptophan | 
                               | 
                            43.2% | 0.11g | |
| Valine | 
                               | 
                            42.1% | 0.45g | 
                          
                      
                                              
                          
                          
                                              
                      A reasonable source of supplementary protein, pumpkin seed is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 2 banana (236g) and 0.3 cup of pumpkin seeds (19g) creates a complete protein profile. The entire range to create a complete protein are ratios of 1:0.08 to 1:39 for banana to pumpkin seed by weight. 
                      
                      
                        Full nutritional profile for pumpkin seeds 
                        USDA Source: Seeds, pumpkin and squash seeds, whole, roasted, without salt
                    
| Amino Acid | % of RDV [2] | Amount [9] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            12.1% | 6g | |
| Histidine | 
                               | 
                            44.1% | 0.28g | |
| Isoleucine | 
                               | 
                            28.4% | 0.24g | |
| Leucine | 
                               | 
                            24% | 0.45g | |
| Lysine | 
                               | 
                            22% | 0.38g | |
| Methionine | 
                               | 
                            11.3% | 0.1g | |
| Phenylalanine | 
                               | 
                            19.3% | 0.29g | |
| Threonine | 
                               | 
                            21.5% | 0.19g | |
| Tryptophan | 
                               | 
                            31.6% | 0.08g | |
| Valine | 
                               | 
                            36% | 0.39g | 
                          
                      
                                              
                          
                          
                                              
                      Poppy seed is a reasonable source of supplementary protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2.5 banana (295g) and 4.7 teaspoons of poppy seeds (13g) make a complete amino acids profile. The entire range to create a complete protein are ratios of 1:0.04 to 1:18 for banana to poppy seed by weight. 
                      
                      
                        Full nutritional profile for poppy seeds 
                        USDA Source: Spices, poppy seed
                    
| Amino Acid | % of RDV [2] | Amount [10] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            11.2% | 5.6g | |
| Histidine | 
                               | 
                            45.9% | 0.29g | |
| Isoleucine | 
                               | 
                            22.1% | 0.19g | |
| Leucine | 
                               | 
                            19.8% | 0.37g | |
| Lysine | 
                               | 
                            15.9% | 0.27g | |
| Methionine | 
                               | 
                            10.4% | 0.09g | |
| Phenylalanine | 
                               | 
                            16.4% | 0.24g | |
| Threonine | 
                               | 
                            19.2% | 0.17g | |
| Tryptophan | 
                               | 
                            19.5% | 0.05g | |
| Valine | 
                               | 
                            26.2% | 0.28g | 
                          
                      
                                              
                          
                          
                                              
                      A reasonable source of supplementary protein, spinach is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 1.4 banana (169g) and 7.5 cups of spinach (225g) creates a complete protein profile. In fact, any ratio of more than 1.3:1 of spinach to banana will be complete. 
                      
                      
                        Full nutritional profile for spinach 
                        USDA Source: Spinach, raw
                    
| Amino Acid | % of RDV [2] | Amount [11] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            16.5% | 8.3g | |
| Histidine | 
                               | 
                            43.5% | 0.27g | |
| Isoleucine | 
                               | 
                            43.9% | 0.38g | |
| Leucine | 
                               | 
                            32.6% | 0.62g | |
| Lysine | 
                               | 
                            27.8% | 0.48g | |
| Methionine | 
                               | 
                            15.4% | 0.13g | |
| Phenylalanine | 
                               | 
                            25% | 0.37g | |
| Threonine | 
                               | 
                            35.7% | 0.32g | |
| Tryptophan | 
                               | 
                            39.5% | 0.1g | |
| Valine | 
                               | 
                            40.8% | 0.44g | 
                          
                          
                                              
                      Flaxseed is a reasonable source of supplementary protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 1.7 banana (197g) and 2.4 tablespoons of flaxseeds (24g) make a complete amino acids profile. In fact, any ratio of more than 0.12:1 of flaxseed to banana will be complete. 
                      
                      
                        Full nutritional profile for flaxseeds 
                        USDA Source: Seeds, flaxseed
                    
| Amino Acid | % of RDV [2] | Amount [12] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            13.2% | 6.6g | |
| Histidine | 
                               | 
                            42.3% | 0.27g | |
| Isoleucine | 
                               | 
                            31.8% | 0.27g | |
| Leucine | 
                               | 
                            23% | 0.44g | |
| Lysine | 
                               | 
                            18% | 0.31g | |
| Methionine | 
                               | 
                            12.3% | 0.11g | |
| Phenylalanine | 
                               | 
                            22.1% | 0.33g | |
| Threonine | 
                               | 
                            26.9% | 0.24g | |
| Tryptophan | 
                               | 
                            34.6% | 0.09g | |
| Valine | 
                               | 
                            32.8% | 0.35g | 
                          
                      
                                              
                          
                          
                                              
                      A reasonable source of supplementary protein, lotus seed is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 0.8 banana (98g) and 1.5 cups of lotus seeds (47g) creates a complete protein profile. In fact, any ratio of more than 0.48:1 of lotus seed to banana will be complete. 
                      
                      
                        Full nutritional profile for lotus seeds 
                        USDA Source: Seeds, lotus seeds, dried
                    
| Amino Acid | % of RDV [2] | Amount [13] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            16.6% | 8.3g | |
| Histidine | 
                               | 
                            44% | 0.28g | |
| Isoleucine | 
                               | 
                            44.8% | 0.39g | |
| Leucine | 
                               | 
                            33.6% | 0.64g | |
| Lysine | 
                               | 
                            29.8% | 0.51g | |
| Methionine | 
                               | 
                            15.4% | 0.13g | |
| Phenylalanine | 
                               | 
                            27.3% | 0.41g | |
| Threonine | 
                               | 
                            41.9% | 0.38g | |
| Tryptophan | 
                               | 
                            43.1% | 0.11g | |
| Valine | 
                               | 
                            47.2% | 0.51g | 
                          
                          
                                              
                      Kiwi is low in protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2 banana (236g) and 5.6 kiwi (387g) make a complete amino acids profile. The entire range to create a complete protein are ratios of 1:1.6 to 1:4 for banana to kiwi by weight. 
                      
                      
                        Full nutritional profile for kiwi 
                        USDA Source: Kiwifruit, green, raw
                    
| Amino Acid | % of RDV [2] | Amount [14] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            14% | 7g | |
| Histidine | 
                               | 
                            45.4% | 0.29g | |
| Isoleucine | 
                               | 
                            30.6% | 0.26g | |
| Leucine | 
                               | 
                            22% | 0.42g | |
| Lysine | 
                               | 
                            20.7% | 0.35g | |
| Methionine | 
                               | 
                            13% | 0.11g | |
| Phenylalanine | 
                               | 
                            19.2% | 0.29g | |
| Threonine | 
                               | 
                            27.5% | 0.25g | |
| Tryptophan | 
                               | 
                            30.6% | 0.08g | |
| Valine | 
                               | 
                            30.7% | 0.33g | 
                          
                      
                                              
                          
                          
                                              
                      A great source of protein, dijon mustard is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 1.3 banana (148g) and 3.6 tablespoons of dijon mustard (22g) creates a complete protein profile. In fact, any ratio of more than 0.15:1 of dijon mustard to banana will be complete. 
                      
                      
                        Full nutritional profile for dijon mustard 
                        USDA Source: Spices, mustard seed, ground
                    
| Amino Acid | % of RDV [2] | Amount [15] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            14.5% | 7.2g | |
| Histidine | 
                               | 
                            48.1% | 0.3g | |
| Isoleucine | 
                               | 
                            34.5% | 0.3g | |
| Leucine | 
                               | 
                            29.1% | 0.55g | |
| Lysine | 
                               | 
                            27.6% | 0.47g | |
| Methionine | 
                               | 
                            13.5% | 0.12g | |
| Phenylalanine | 
                               | 
                            21.8% | 0.33g | |
| Threonine | 
                               | 
                            24.7% | 0.22g | |
| Tryptophan | 
                               | 
                            26.3% | 0.07g | |
| Valine | 
                               | 
                            36.6% | 0.4g | 
                          
                      
                                              
                          
                          
                                              
                      Pistachio is a great source of protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 1.1 banana (131g) and 0.3 cup of pistachio (33g) make a complete amino acids profile. In fact, any ratio of more than 0.25:1 of pistachio to banana will be complete. 
                      
                      
                        Full nutritional profile for pistachio 
                        USDA Source: Nuts, pistachio nuts, dry roasted, without salt added
                    
| Amino Acid | % of RDV [2] | Amount [16] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            16.7% | 8.4g | |
| Histidine | 
                               | 
                            44% | 0.28g | |
| Isoleucine | 
                               | 
                            41% | 0.35g | |
| Leucine | 
                               | 
                            34% | 0.64g | |
| Lysine | 
                               | 
                            26.8% | 0.46g | |
| Methionine | 
                               | 
                            15.6% | 0.13g | |
| Phenylalanine | 
                               | 
                            29.6% | 0.44g | |
| Threonine | 
                               | 
                            30.2% | 0.27g | |
| Tryptophan | 
                               | 
                            37.7% | 0.1g | |
| Valine | 
                               | 
                            45.6% | 0.49g | 
                          
                      
                                              
                          
                          
                                              
                      Low in protein, mayonnaise is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 2.5 banana (295g) and 0.6 cup of mayonnaise (143g) creates a complete protein profile. In fact, any ratio of more than 0.48:1 of mayonnaise to banana will be complete. 
                      
                      
                        Full nutritional profile for mayonnaise 
                        USDA Source: Salad dressing, mayonnaise, regular
                    
| Amino Acid | % of RDV [2] | Amount [17] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            9.2% | 4.6g | |
| Histidine | 
                               | 
                            42% | 0.26g | |
| Isoleucine | 
                               | 
                            20.4% | 0.18g | |
| Leucine | 
                               | 
                            17.8% | 0.34g | |
| Lysine | 
                               | 
                            14.6% | 0.25g | |
| Methionine | 
                               | 
                            8.6% | 0.07g | |
| Phenylalanine | 
                               | 
                            15.2% | 0.23g | |
| Threonine | 
                               | 
                            17.9% | 0.16g | |
| Tryptophan | 
                               | 
                            19.6% | 0.05g | |
| Valine | 
                               | 
                            22.6% | 0.24g | 
                          
                      
                                              
                          
                          
                                              
                      Sour cream is a reasonable source of supplementary protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2.5 banana (295g) and 0.4 cup of sour cream (72g) make a complete amino acids profile. In fact, any ratio of more than 0.24:1 of sour cream to banana will be complete. 
                      
                      
                        Full nutritional profile for sour cream 
                        USDA Source: Cream, sour, cultured
                    
| Amino Acid | % of RDV [2] | Amount [18] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            9.9% | 5g | |
| Histidine | 
                               | 
                            46.6% | 0.29g | |
| Isoleucine | 
                               | 
                            23.3% | 0.2g | |
| Leucine | 
                               | 
                            22.9% | 0.43g | |
| Lysine | 
                               | 
                            20.2% | 0.35g | |
| Methionine | 
                               | 
                            9.3% | 0.08g | |
| Phenylalanine | 
                               | 
                            17.3% | 0.26g | |
| Threonine | 
                               | 
                            20.5% | 0.18g | |
| Tryptophan | 
                               | 
                            21.8% | 0.06g | |
| Valine | 
                               | 
                            25.8% | 0.28g | 
                          
                      
                                              
                          
                          
                                              
                      A reasonable source of supplementary protein, whipping cream is high in isoleucine and methionine,  which is complementary to banana. 
A ratio of 2.5 banana (295g) and 1.6 cups of whipping cream (98g) creates a complete protein profile. In fact, any ratio of more than 0.33:1 of whipping cream to banana will be complete. 
                      
                      
                        Full nutritional profile for whipping cream 
                        USDA Source: Cream, whipped, cream topping, pressurized
                    
| Amino Acid | % of RDV [2] | Amount [19] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            12.7% | 6.3g | |
| Histidine | 
                               | 
                            49.5% | 0.31g | |
| Isoleucine | 
                               | 
                            31.6% | 0.27g | |
| Leucine | 
                               | 
                            26.8% | 0.51g | |
| Lysine | 
                               | 
                            23.1% | 0.4g | |
| Methionine | 
                               | 
                            11.8% | 0.1g | |
| Phenylalanine | 
                               | 
                            19.8% | 0.29g | |
| Threonine | 
                               | 
                            24.8% | 0.22g | |
| Tryptophan | 
                               | 
                            27.2% | 0.07g | |
| Valine | 
                               | 
                            32.2% | 0.35g | 
                          
                          
                                              
                      Unsalted butter is low in protein, and  is high in isoleucine and methionine,  complementing the profile of banana. 
For example, 2.5 banana (295g) and 1.7 cups of unsalted butter (380g) make a complete amino acids profile. In fact, any ratio of more than 1.3:1 of unsalted butter to banana will be complete. 
                      
                      
                        Full nutritional profile for unsalted butter 
                        USDA Source: Butter, without salt
                    
| Amino Acid | % of RDV [2] | Amount [20] | 
                            Complete / Adequate  | 
                        |
| Protein | 
                               | 
                            12.9% | 6.4g | |
| Histidine | 
                               | 
                            50% | 0.31g | |
| Isoleucine | 
                               | 
                            32.2% | 0.28g | |
| Leucine | 
                               | 
                            27.3% | 0.52g | |
| Lysine | 
                               | 
                            23.5% | 0.4g | |
| Methionine | 
                               | 
                            12% | 0.1g | |
| Phenylalanine | 
                               | 
                            20.2% | 0.3g | |
| Threonine | 
                               | 
                            25.2% | 0.23g | |
| Tryptophan | 
                               | 
                            27.7% | 0.07g | |
| Valine | 
                               | 
                            32.9% | 0.36g |