Nutrition info for a banana is quite unique and it may vary little depending upon the type of banana.
A fully ripened banana has high sugar content and falls under high glycemic food. Whereas a half ripened banana has a bit low sugar content and falls under low glycemic food.
Therefore banana is unique in its property. It can be used during weight loss or during weight gain as an essential food item.
Here is complete nutrition info for a banana 
An average banana is approximately 100-120 grams. We are giving the nutrition info for a banana of 100 grams. You can evaluate the value of a bigger sized banana in the same proportion.
100grams of banana contains
Water = 74.91g
Fat = 0.33g
Sugar = 12.23g [This depends on how much ripened the banana is]
Calcium Ca- 5mg
Potassium K = 358mg
Phosphorus P = 22mg
Iron Fe = 0.26mg
It also contains Vitamin A, B6, Thiamin, C, K, and a few other minerals.
The average weight of one banana is approximately 130 grams. After understanding the above-mentioned nutrition info for a banana you can calculate that each banana at an average contains approximately 120 calories.
The energy in one banana
Three different macronutrients in a banana are responsible for the total calories. Calories from each macronutrient is as follows
Carbohydrates – 93%
Protein – 4%
Fat – 3%
The daily calorie requirement for an average person is 2400 calories
The average person here means that the person has a medium weight to height ratio and does a medium level of activities.
Thus a single banana can take care of 5% of your daily calorie requirement.
As per the nutritional info of a banana as described above you will require to burn a minimum of 120 calories.
You will require to do any one of the following to burn calories obtained from one banana.
Weight lifting – Nominal
You will require to do weight lifting training in a nominal proportion for a minimum of 30 minutes. This is if your weight is 60kg or 133 pounds. If the weight is less then you will require to spend some extra minutes in the same proportion.
Weight lifting also helps to improve your muscle tone which in turn keeps burning calories even after your weight-training exercise is over. Thus you get double benefits.
This also helps to improve body posture and reduce stress on the skeletal structure of your body.
Aerobics of low impact
Aerobics burn calories quickly. So even a low impact aerobics of 20 minutes will burn calories equivalent to one banana
Banana also contains various minerals and vitamins like Potassium, Vitamin B6, Vitamin
A 30-minute normal walk can burn those 120 calories you gained from eating one banana. Calories in banana give you enough energy to walk for 30 minutes in a normal phase.
If you increase the phase to medium or fast then the time required to burn calories equivalent to one banana will also reduce.
15 minutes of fast bicycling can help burn 120 calories easily. This is the easiest and fastest exercise that you can do if you want to get rid of calories from the banana you ate.
12 minutes of running can burn 120 calories. But, remember the running should be moderate to fast. If you are jogging slowly then you will require around 20 minutes.
A fast phased dancing can burn around 120 calories in 20 minutes. Enjoy while burning your calories.
After having understood the nutrition info for a banana, you should now understand the benefits of banana. 
Nutrition info for a banana explained 
Banana has all the essential macro and micronutrients. I have tried to explain the benefit of each below.
Carbohydrate is the main macronutrient in banana. A medium-sized banana may contain 23g of carbohydrates. Banana is a great and cheap source of energy because of this very property. A medium-sized banana has almost 12g of sugar.
Banana is a high glycaemic food. Therefore, it releases energy quickly. Therefore, people undergoing intense weight training consume it few hours before exercise. Banana, for this very property, is also consumed for weight gain.
Starch in banana. 
Banana has a very unique property that makes it different from all other fruits. This uniqueness is due to the starch present in the banana.
An unripe banana contains 80% of carb in starch form. But, this starch is not the normal starch.
The starch in a banana is the resistant starch. This starch doesn’t get digested quickly in the body. This makes an unripe banana a low glycaemic food.
An unripe banana is therefore used in weight loss diet plans because of the resistant starch and low glycaemic index value.
As the banana ripens, the starch starts getting converted to sugar. A full ripened banana has a high content of sugar (12.8g / 100 g of banana) and is high in glycaemic index.
So a ripened banana is used in a weight gain diet plan or for people who want quick energy.FatBanana has a very low percentage of fat. Therefore, the energy generated from 100 g of banana is less than energy generated from 100g of avocado that is rich in fat but low in carbohydrate.ProteinBanana is also low in protein. It contains only 1.9g of protein.
Potassium is good for heart and blood pressure.
Banana also contains various other minerals as discussed above under the nutrition info of a banana.
A single banana contains approximately 35% of your daily dietary requirement of Vitamin B6.
Similarly banana contains a good quantity of vitamin C.
Banana has many healthy properties that depending on the macro and micronutrients it has.
I have explained some great health benefits of banana below.
Health Benefits of banana
After knowing the nutrition info for a banana you might understand that banana is packed with different nutrients. Therefore, banana has many benefits in different ailments.
Let us understand each benefit of banana for health one by one.
Win your hunger with banana:
It is a great anytime snack to satisfy hunger pangs. Banana is one superfood that also helps to cure many diseases.
A regular intake of bananas can help you cure these common problems:
Premenstrual syndrome (PMS)
Though PMS is not a disease, most women will not want the pains that come every month with their periods.
PMS affects a woman’s physical health, emotions, and behavior. It is a very common problem and 90% of menstruating women suffer from this.
Bananas are helpful to reduce the pain during the periods.
Vitamin B6 found in bananas also helps to control blood glucose levels and thus limiting the emotional mood swings during the menstrual cycle.
Interestingly, taking a vitamin B6 pill will not give you the same effect. By including bananas in daily diet and more before the periods, women can help reduce PMS problems.
The biggest problem that people face today is obesity. The other that is commonly associated with it is high blood pressure.
We consume foods that are processed and contain a high amount of sodium. This type of food is responsible for blood pressure problems. Having one or two bananas daily can help to lower the high blood pressure.
Bananas are rich and potassium and contain low sodium and therefore reduce the risk of other heart diseases like stroke.
It may sound odd, but yes, bananas can also help reduce depression problems. People suffering from depression undergo many kinds of struggles.
Such people mostly feel body pain and remain tired throughout and most of them end up with fibromyalgia which is a heavy physical and mental pain.
Though bananas won’t cure all your depression, they can help in a good way to reduce the effects.
Bananas are known to contain a protein called tryptophan which converts the protein in our body into Serotonin. Serotonin is a feel-good protein and it makes the brain feel happy and relaxed.
You can also overcome your mood related problem with bananas.
Constipation is also a very common problem for many people. Being constipated for a longer time makes life harder as you cannot enjoy anything.
Bananas are a good and easy cure for constipation. By adding bananas in your diet can help you relieve the problem.
Being rich in fiber content bananas are good for any kind of stomach problem and thus help to avoid laxatives. Bananas can be eaten raw or as shakes.
This will help to keep the stomach easy and fresh by keeping the constipation problem away.
Problems related to Brain
Our brain is the most important part of our body and so we need to take proper care of our brain.
Any brain-related problem will go a long way to affect our whole body.
Bananas are also helpful in avoiding any brain-related problems. Bananas are a rich source of potassium which is important to maintain good brain health.
Including bananas in our daily diet can help keep the brain in good shape and functioning properly.
Mosquitoes are one of the most annoying insects and spread many deadly diseases too.
A mosquito bite can give an allergic itchy reaction to the skin.
Surprisingly the banana peel can be a handy cure for a mosquito bite. For immediate relief from a mosquito bite, rub the inside of the banana peel on the affected area.
This will help to stop the swelling on the skin and the irritation will be controlled in some time.
Banana is good for the heart
Banana contains a lot of potassium. Potassium is an important mineral that balances sodium in the body.
If the potassium drops in the body it leads to the rising of sodium. This is dangerous for the heart. A balance between sodium and potassium is important for many organs including the heart.
So banana can be a great fruit that supplies your body with this essential mineral.
But, always remember that if you are struggling with weight problems and are obese then you should consume banana in moderation.