We've heard about an apple a day, but in Bermuda a banana a day may be what we should all be aiming for.The fruit's high potassium content provides powerful protection against atherosclerosis and high blood pressure, which affects more than a quarter of Bermudians.It's also a natural stomach antacid and contains compounds that protect the entire digestive tract.Buying Bermuda bananas is best to avoid the effects of imported ones that are usually treated with ethylene gas.Every week Body & Soul highlights an in-season produce item. This week's focus is the banana.Scientific name: musa sapienta, musa nana.Family of: muscae.Related to: lilies and orchids.Grown: in Bermuda.Vitamin content: an excellent source of vitamins B6 (pyridoxine) and C.Mineral content: a good source of potassium and a good source of manganese copper, phosphorus, iron and magnesium.Dietary fibre: A very good source with about 2.83 grams in one cup of the boiled vegetable.Omega 3 fatty acids: Bananas do not contain omega three fatty acids.Calories: One banana has about 108.56 calories.Good for: A rich source of potassium, bananas are thought to help prevent high blood pressure and cholesterol build-up in arteries. This makes it a good protection against cardiovascular disease.Bananas also protect the lining of the stomach from acid damage. This also means it protects ulcers from forming in the stomach. Research has shown that it does this by activating cells that line the stomach to produce more mucous which forms a barrier against the powerful stomach acids. Bananas also contain substances that help eliminate specific stomach bacteria that have been identified as the primary cause of stomach ulcers.Bananas also contain compounds that nourish probiotic bacteria in the colon. These beneficial bacteria produce vitamins and enzymes that improve nutrient absorption in the body. Additionally when the probiotic bacteria ferment these compounds, not only do the numbers of those beneficial bacteria rise, but the body's ability to absorb calcium is also increased. This makes bananas a good way of maintaining healthy bones.Green bananas contain short-chain fatty acids that are a favourite food of cells that line the intestine. When these cells are well nourished they dramatically increase the body's ability to absorb nutrients like calcium. High in pectin, bananas help ease material through the digestive tract. They are particularly helpful for those who suffer with constipation. While they are a sugary fruit their glycemic index is significantly lower (about 30 compared to 60) when they are not fully ripe.How to judge ripeness: Some people boil green bananas so ripeness really depends on your personal preference for this fruit. Its sugar content increases the more ripe it is, so for diabetics and others watching their sugar intake eating a light yellow banana that is beginning to ripen is a better option than a fully ripe one. Look for Bermuda bananas or organic ones especially if you are allergic to latex. Bananas are associated with latex allergies and imported ones that are not organic have usually been treated with ethylene gas, which increases the enzymes in the fruit that trigger the allergy.