In the long sea-going travels between the 16th, 15th century which is also called the Age of Discovery, sailors were able to see visions of exquisite food and lush fields. The realization that these visions were just visions after months of sailing was agonizing. Some sailors cried out in pain while others threw themselves off the boat.
It was thought that the solution to these horrifying omens would be the combination of complicated chemicals. However, it was found that the cure was easy lemon juice. The sailors who suffered from scurvy, which is a condition due to vitamin C deficiency. Vitamin C is a crucial micronutrient that can be obtained by eating vegetables and fruits.
Vitamin C is essential for the release and production of neurotransmitters. These are chemical messengers that are used to communicate with the brain. If it isn’t there, neurons will not effectively communicate with each other, which can cause hallucinations.
As this well-known example of early explorers demonstrates that there is a strong connection between brain and food and brain, a connection that scientists like me are trying to understand. As a scientist researching the neurobiology of food in the University of Michigan, I am most interested in the ways ingredients in food and their breakdown products alter the genetic instructions which regulate the physiology of our bodies.
Aside from that, a further goal of my work is to discover how food choices affect our moods, thoughts and behavior. Although we aren’t able to prevent or treat mental disorders with nutrition, scientists like myself are discovering a large amount about the importance that nutrition plays in everyday brain processes that shape us into our identity.
Perhaps not so surprising, an optimum balanced intake of nutrition is crucial to the health of your brain: Deficiencies or excesses of sugars, vitamins, fats and amino acids may influence the brain and behavior in both positive and negative ways.
Mineral deficiencies and vitamin deficiencies
Similar to vitamin C, deficiencies in the other minerals and vitamins may also cause nutritional illnesses that can negatively affect the brain of humans. For example, low quantities of vitamin B3/niacin normally found in fish and meat can cause pellagra, the disease that causes individuals to suffer from dementia.
Niacin is essential to the body to transform food into energy, and to build blocks, safeguard the blueprint of genetics from environmental harm and regulate the amount of specific gene products are produced. Without these crucial processes brain cells, also called neurons, fail and begin to die prematurely. This can cause dementia.
In animal models, reducing or preventing the production of Niacin inside the brain causes the destruction of neurons and cells. However the increase in niacin levels have been proven to reduce the negative effects of neurodegenerative disorders like Alzheimer’s, Huntington’s, and Parkinson’s. Although the findings are not conclusive, studies of observation on humans suggest that adequate levels of niacin could be able to protect against these illnesses.
It is interesting to note that niacin deficiencies due to excessive consumption of alcohol could cause similar symptoms to those seen in the pellagra.
Another way to illustrate the impact of a nutritional deficiency on brain function can be seen in the element iodine that, like niacin is a requirement in the diet. It is naturally found in seaweed and seafood and is also acquired through Iodized salt. Iodine is a vital element in the production of thyroid hormones – signaling proteins that are crucial for many elements of our biology. These include metabolism, growth, appetite and sleep. Insufficient levels of iodine hinder the production of sufficient amounts of thyroid hormones, causing impairment to the essential biological processes.
Iodine is crucial for the human brain’s development. Indeed, before the introduction of table salt using this mineral as early as the 1920s iodine deficiencies was a major reason for cognitive impairment across the globe. Iodized salts is believed to have contributed to the steady rise in IQ scores over the last century.
Dietary ketogenic for epilepsy
Some dietary deficiencies are harmful to the brain. In fact, research shows that people with drug-resistant epilepsy – a condition in which brain cells fire uncontrollably – can reduce the number of seizures by adopting an ultralow-carbohydrate regimen, known as a ketogenic diet, in which 80% to 90% of calories are obtained from fat.
Carbohydrates are a preferred fuel source for our bodies. If they’re not readily accessible – whether due to fasting or the ketogenic diet – cells get the energy they require by breaking them down into compounds known as ketones. Utilizing ketones to generate energy triggers a number of changes in physiology and metabolism, including the level of hormones within your body. It also affects the quantity of neurotransmitters created in the brain as well as the different kinds of bacteria found in the digestive tract.
Researchers believe that these diet-dependent changes, particularly the increased levels of neurochemicals that calm neurons and reduce levels of inflammatory substances could play a part in the ability of the ketogenic diet to reduce the frequency of seizures. These changes could also help explain the advantages of ketogenic states which is achieved through fasting or diet on cognition and mood.
Certain foods can adversely impact your mood and memory.
Sugar, saturated oils and ultra-processed food items
In excess levels of certain nutrients may also have negative affects to the brain. In both animal and human models the consumption of high levels of saturated fats and refined sugars which are common in foods that are processed to the point of being a source of eating by de-sensitizing the brain to the hormone signals that are known to regulate feelings of fullness as well as satisfaction.
In a fascinating way, a diet rich in these foods can also de-sensitize the taste system, causing people and animals see food as being less sweet. The changes in sensory perception can impact food selection and the pleasure we receive from food. Studies have shown, for instance that the responses of people to ice creams in brain regions that are responsible for pleasure and taste are diminished when they consume the same amount of ice cream every day over a period of two weeks. Researchers believe that this reduction in the reward signal for food could cause a rise in cravings for fat-laden and sugary food items like the way smokers are drawn to cigarettes.
Foods with high levels of fat and processed ingredients are also linked to reduced cognition and memory in both animal and human models, and an increased risk of developing neurodegenerative diseases. But, researchers do not know if these effects are caused by these foods or due to obesity or insulin resistance can develop when you consume these diets.
This is a crucial aspect of the effects that diet has on our brain time. Certain foods can affect brain function and behavior quickly for a period of time – like over several days or hours – however, others can require months, weeks, or even years before they can have an impact.
For instance eating a slice of cake can quickly change the ketogenic metabolism that burns fat of someone with epilepsy resistant to medication into a carbohydrate-burning metabolism, which increases the risk of developing seizures. However it takes several weeks of consumption of sugar to experience the taste, as well as your brain’s reward pathway change as well as months in deficiency of Vitamin C before they be diagnosed with the condition known as scurvy. When it comes to illnesses like Parkinson’s and Alzheimer’s, chances of developing them are affected by the cumulative effects of exposure to dietary factors along with lifestyle factors like smoking.
The connection between food and the brain is similar to the delicate Goldilocks story: It is not necessary to have excessively little, nor excessively, but enough of each nutrients.
The article was written by Monica Dus, Associate Professor of Molecule, Cellular, and Developmental Biology, University of Michigan.
The article first appeared by The Conversation.