Bananas are a widely consumed fruit both as a popular snack and with culinary and industrial applications. While native to Southeast Asia, bananas are now grown in tropical climates around the world. Additionally, bananas do not have seasonal growth restrictions, making them an accessible option year-round.
Bananas offer several brain-boosting benefits due to their rich nutritional profile.
They are an excellent source of vitamin B6, which is crucial for the production of neurotransmitters like serotonin and dopamine that regulate mood and cognitive function. The high potassium content in bananas helps maintain proper nerve function and enhances communication between brain cells.
Additionally, bananas contain antioxidants, such as dopamine and vitamin C, which protect brain cells from oxidative stress and inflammation. Consuming bananas can also support memory and learning by providing a steady supply of glucose, the brain’s primary energy source. These combined effects make bananas a valuable addition to a diet aimed at maintaining and improving brain health.
Read on to discover the research and scientific evidence that links bananas with these health benefits.
To date, there have been several large cohort studies that provide evidence on the positive impact of fruit and vegetable consumption on mental health. One of the proposed mechanisms of depression is a decrease in serotonin in the central nervous system. Serotonin is a neurotransmitter that regulates key functions like mood, appetite and sleep. This understanding guides the rationale behind the use of medications that increase serotonin levels to treat depressive symptoms.
The humble banana is a rich source of tryptophan, an essential amino acid that serves as a building block for the body to produce serotonin. Serotonin’s influence on mood makes tryptophan significant for mental health, potentially affecting conditions like depression and anxiety.
An Australian team of scientists published a review article in the journal Nutrients in 2016 highlighting the effects of tryptophan consumption on mood, sleep and cognition. In animal models, they show that low dietary tryptophan levels have both an anxiogenic and depressant effect on the behaviour of study animals. When rats were fed a low tryptophan-containing diet for one month, they displayed anxiety-like and behaviours in multiple tests that were conducted by the researchers.
Interestingly in human research, there seems to be a gender-specific effect of low tryptophan levels. In a group of healthy volunteers, a diet depleted in tryptophan had more marked effects on female individuals with minimal effect on the male participants.
Tryptophan has also been found to have direct effects on cognition and sleep in studies performed amongst human and animal subjects. In a 2015 study published in the British Journal of Nutrition, a population of otherwise healthy females aged between 45-65 were randomized to receive either a tryptophan dietary supplement or placebo in addition to their general diet. The authors investigated the effect of the addition of tryptophan on cognitive and emotional functions, mood, and quality of sleep.
The study found those who consumed the supplement had improvements in emotional and cognitive processing speed as well as improvements in levels of attention. Notably, when the participants consumed the supplement 60-90 minutes before bedtime, feelings of calmness and happiness were consistently reported. The hypothesis proposed by the authors was that the tryptophan-containing supplement likely improved serotonin synthesis in the brain, leading to beneficial effects on cognitive and emotional functions.
While bananas are not the highest source of tryptophan compared to other foods like turkey or cheese, their overall nutritional profile, including vitamins, minerals, and fiber, makes them a valuable and accessible source of this essential amino acid. The presence of tryptophan in bananas adds to their role in promoting mental and physical health, making them a beneficial addition to a balanced diet.
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