The Nexus between Diet and Behaviour

Researchers have found a link between your diet and your behaviour. Certain foods affect the level of neurotransmitter substances in your brain and this in turn affects your mood, behaviour and mental performance. Science has established the saying “You are what you eat” to be true on the basis of how different foods affect brain functions and consequently behaviour and health status.

In my medical practice, I have experienced diminished mental performance after particular meals in the morning; this phenomenon has been described as “brain fog”. Brain fog arises from the diversion of blood circulation from the brain to the intestines. A General Medical Practitioner in Nigeria on a busy day could see a bewildering array of different medical conditions that beg for diagnosis, investigations and treatment; brain fog could become a distraction a busy doctor can ill afford. I have since learned to stay away from foods that cause brain fog in the morning.

Researchers have classified certain foods as “brain food” because they improve cognitive function when eaten. Cognitive function by definition is the process of thinking and knowing that is mediated by the brain. How your brain functions determines how much of a success you would make of the chances that come your way in life. Whatever you eat that promotes cognitive vitality does this by affecting the levels of different neurotransmitter substances [also known as chemical messengers] in the brain. Brain foods increase cognitive vitality by increasing the reserve brain capacity as well as protecting the brain from oxidative damage caused by free radicals.

Three of the most important of these neurotransmitters are dopamine, serotonin and acetylcholine. Neurotransmitters mediate intercellular communication among brain neurons; their lack is associated with different health conditions of the brain and mind. They work by either stimulating [excitatory function] or inhibiting transmission at the nerve endings and these reflect on the mood and actions of the person.

Dopamine stimulates brain function resulting in locomotion, emotional arousal, good attention span and learning; it also inhibits some aspects of brain function. Excess of dopamine in the brain has been linked with Schizophrenia while its deficiency is the underlying cause of Parkinson’s disease. Parkinson’s disease is characterized by tremors, poverty or limitation of movement and unstable gait. All proteinous foods such as eggs, fish and meat are rich in dopamine.

Acetylcholine has been described as the dominant player in the formation of memory in the amygdala, which is a part of the brain. It is involved in behaviour regulation and voluntary muscle movement. Deficiency of acetylcholine is the underlying cause of Alzheimer’s disease; a debilitating and socially isolating condition that presents with progressive memory loss. Food substances that help the body synthesize ample amounts of acetylcholine are peanuts, wheat gem, egg yolks, fish, liver, meat, and vegetables such as broccoli, cabbage and cauliflower.

Serotonin is another neurotransmitter which is abundantly present in starchy foods, vegetables and cereals. When it subserves an inhibitory function in the brain, it controls arousal, sleep, mood and appetite. When serotonin stimulates the brain, it produces feelings of pleasure. Deficiency of serotonin is one of the underlying causes of depression.

Diets loaded with macro and micronutrients such as minerals and Vitamins A, B, C, D and E help the body function properly. Vitamin D helps the bones of the body while Vitamins A C and E are power antioxidants that function to protect cells from oxidative damage resulting from free radicals. Vitamin B is a key component of the enzymatic system in the body and it plays a pivotal role in cellular processes that provide energy to the body.

An adult requires between 1.5 and 2 liters  of water to stay hydrated in 24 hours. Water serves to carry nutrients round the body, is a medium of exchange of electrolytes in the body and it carries wastes to the kidneys for excretion. You must take adequate amount of water daily to stay hydrated. In hot weather, you loose more water and the mechanism of thirst makes you drink more water to correct the deficit. In cold weather, you lose less and consequently drink less water.

Omega-3 oils are good fats that are present in deep sea oily fish, sardines and tuna; when deficient in the body, it can lead to poor mental performance. Adequate intake of these oils is helpful to the brain, heart and joints.

In conclusion, your choice of diet should be determined by the work at hand, the time of the day, and your health status. Take proteinous foods in the mornings to stimulate your brain to function optimally and keep you alert in a working mode. Reserve carbohydrate diet for evenings when it will make you calm, relaxed and ready for sleep. As you age, take liberal amounts of supplements to make up for inadequate dietary intake of these substances.