During the long voyages of the 15th and 16th centuries, known as the Age of Discovery, sailors reported experiencing visions of sublime food and lush fields. After spending months at sea, the discovery that these were nothing more than hallucinations was painful. Some sailors wept with longing. Others threw themselves overboard.
The remedy for these disastrous mirages turned out not to be a complex chemical concoction as once suspected, but rather a simple lemon juice antidote. He suffered from scurvy, a disease caused by a deficiency of vitamin C, an essential micronutrient obtained from eating vegetables and fruits.
Vitamin C is important for the production and release of neurotransmitters, chemical messengers in the brain. With a deficiency, brain cells cannot communicate effectively with each other, which can lead to hallucinations.
As this early explorer’s famous example shows, there is a close link between food and the brain that researchers like myself are working to understand. As a researching scientist, I am primarily interested in how food components and their breakdown products can alter the genetic instructions that control our physiology.
Beyond that, my research is also focused on understanding how food affects our thoughts, moods, and behavior. However, researchers like myself are learning a lot about the role nutrition plays in the daily brain processes that shape us.
Not surprisingly, a delicate balance of nutrients is key to brain health. Deficiency or excess of vitamins, sugars, fats and amino acids can have negative or positive effects on the brain and behavior.
lack of vitamins and minerals
Similar to vitamin C, deficiencies in other vitamins and minerals can also cause nutritional disorders that adversely affect the human brain. It causes pellagra, a disease that leads to dementia.
Niacin is essential for turning food into energy and building blocks, protecting our genetic blueprint from environmental damage, and controlling the amount of certain gene products. brain cells that are affected by the disease become dysfunctional, leading to premature death and dementia.
Reducing or blocking niacin production in the brain promotes neuronal damage and cell death in animal models. It has been shown to reduce the effects of disease. Observational studies in humans suggest that adequate levels of niacin may protect against these diseases, but results are still inconclusive. There is none.
Interestingly, niacin deficiency caused by the consumption of excessive amounts of alcohol can have effects similar to those seen with pellagra.
Another example of how nutrient deficiencies can affect brain function is found in iodine, which, like niacin, must be obtained from the diet. , is an essential component of thyroid hormone, a signaling molecule important to many aspects of human biology, including sleep. Low iodine levels prevent the production of sufficient amounts of thyroid hormones, impairing these important physiological processes.
Iodine is particularly important for human brain development. Before table salt was supplemented with this mineral in the 1920s, iodine deficiency was a leading cause of cognitive impairment worldwide. It is believed that
Ketogenic Diet for Epilepsy
Not all dietary deficiencies are detrimental to the brain. In fact, research has shown that people with drug-resistant epilepsy (a condition in which brain cells fire uncontrollably) can reduce the number of seizures by adopting an ultra-low-carb diet known as a ketogenic diet. shown. Calories come from fat.
Carbohydrates are the preferred source of energy for the body. When they are unavailable, either for reasons of fasting or a ketogenic diet, cells obtain fuel by breaking down fat into compounds called ketones. The use of ketones for energy leads to profound changes in metabolism and physiology, including the levels of hormones circulating in the body, the amount of neurotransmitters produced by the brain, and the types of bacteria that live in the gut.
Researchers believe that these diet-dependent changes, particularly higher production of brain chemicals that can calm nerve cells and lower levels of inflammatory molecules, contribute to the ketogenic diet’s ability to reduce the number of seizures. These changes may also explain the cognitive and mood benefits of the ketogenic state with diet and fasting.
Some foods have negative effects on memory and mood.
sugar, saturated fat, and ultra-processed foods
Excessive levels of some nutrients can also have detrimental effects on the brain. It promotes eating by desensitizing the brain to hormonal signals known to regulate satiety.
Interestingly, diets high in these foods desensitize the taste system, making food less sweet in animals and humans. For example, one study found that eating ice cream every day for two weeks blunted the response to ice cream in brain regions important for taste and reward. Some researchers believe that this reduction in food reward signals may further increase cravings for fatty and sugary foods, similar to the way smokers crave cigarettes. increase.
High-fat and processed food diets are also associated with decreased cognitive function and memory in humans and animal models, and increased incidence of neurodegenerative diseases. However, researchers still don’t know if these effects are due to these foods or the weight gain and insulin resistance that occurs with long-term consumption of these meals.
time scale
This brings us to an important aspect of how diet affects the brain: time. Some foods have an acute effect on brain function and behavior over hours or days, while others take weeks, months, or even years to take effect. For example, eating a slice of cake rapidly shifts a fat-burning, ketogenic metabolism to a carbohydrate-burning metabolism in individuals with drug-resistant epilepsy, increasing the risk of seizures. It takes weeks of sugar consumption to change, and months of vitamin C deficiency to develop scurvy. Risk is influenced by dietary exposure over many years in combination with other genetic and lifestyle factors.
After all, the relationship between food and the brain is a bit like a delicate Goldilocks. Each nutrient should be consumed in sufficient quantity, neither too little nor too much.
Monica Dus, Associate Professor of Molecular, Cellular, and Developmental Biology, University of Michigan
This article is republished from The Conversation under a Creative Commons license. Please read the original article.
