Bananas are a nutritious tropical fruit suitable for eating raw or cooked. Including bananas in your diet means you take in a variety of vitamins, minerals and amino acids, including lysine. Your body can't make lysine, so getting it through the foods you eat is critical. While high-protein foods such as poultry or seafood is the best choice for lysine, bananas contribute a small amount.
Lysine in Bananas
One large banana 8 to 8 7/8 inches in length has 0.06 g of lysine. People older than age 13 require 12 mg of this amino acid each day. Note that if you eat a diet high in arginine, which is present in peanuts, coconut, Brazil nuts, oats, wheat, chocolate, soybeans and meats, you may need more lysine in your meal plan, as consuming large quantities of arginine may reduce the level of lysine in your body.
When you experience a herpes outbreak, whether it is in the form of genital herpes, cold sores or shingles, eating bananas may be a smart option. A study published in the July 2011 issue of "The Journal of Biological Chemistry" looked at the effects of lysine against the herpes simplex virus type-1, which trigger cold sores, in a laboratory setting. Researchers determined that lysine is necessary to stop the spread of the virus. More research is needed to determine if this lysine finding correlates to humans and other forms of the herpes virus.
The lysine in bananas may help protect you from osteoporosis, a disease that primarily strikes older adults -- particularly women -- due to a lack of calcium in the bones. Osteoporosis may trigger bone pain, easily fractured bones and stooped posture. The University of Maryland Medical Center website notes that lysine helps your body absorb calcium, which may indicate a potential treatment option to help ward off osteoporosis.
While the amount of lysine in bananas is small, if you consume too many bananas or a diet high in lysine the quantity may prove harmful to your health. High doses of lysine may raise your risk of developing gallstones, which are small deposits that form inside the gallbladder and cause sharp pain, nausea and vomiting. The lysine you take in as part of your regular diet is otherwise safe for consumption.