· The illustrations in this article are done by the author.
Hello, I am Wendy Wu from grade 12. When I read books related to neuroscience (or you can call it ‘brain science’), I am always amazed by the complex and logical mechanisms of our brain functions. Protecting our brains is indeed a big deal for us. However, there is a phenomenon: most people usually prefer to spend lots of money on cosmetic medicine, but often ignore the importance of their daily diets, circadian rhythm, etc., in affecting their body and mind.
Therefore, I decide to open a blog to share some exciting knowledge in neuroscience and raise people’s awareness in protecting their brains through preventative measures.
In this article, I will introduce the idea of neuroplasticity (神经可塑性) and delve into the importance of nutrition in affecting it. After that, I will focus on what kinds of foods your brain “likes to eat” and how they boost your brain’s energy. In the end, there will be a summary to highlight the foods that you could include in your daily diet.
Before I start talking about neuroplasticity, let me introduce a girl called Michelle Mack. Michelle was born with only the right hemisphere of the brain, but surprisingly, she could speak fluently, graduated from high school and lived normally. When she was 27 years old, the doctor determined that the right side of her brain essentially took over the function that her ‘left brain’ was supposed to present. The example of Michelle showed us the incredible power of neuroplasticity (神经可塑性), which is defined as “the ability of the brain to change and adapt”. In other words, it’s the ability that the brain rewires its structure by generating new cells, establishing neural circuits and developing its function through adapting to various experiences throughout your whole life. However, the prerequisite for neuronal generation is the preservation of the brain’s resilience. One of the ways to achieve this is to obtain healthy foods.
Your brain is “scared” of oxidative stress (氧化应激) - the imbalance of free radicals (自由基) and antioxidants (抗氧化剂) in your body, which damages cells and tissue. Oxidative stress might lead to developing a series of diseases, including cancer, diabetes, heart disease and neurodegenerative diseases.
Scientists have found that neurotrophic factors and antioxidants play an essential role in slowing down oxidative stress.
Antioxidants prevent oxidative stress through the removal or neutralization of free radicals. On the other hand, neurotrophic factors (神经营养因子) are the proteins secreted that promote essential functions in synaptic and neuronal growth, myelination (髓鞘形成), differentiation, and survival. Two main neurotrophic factors are associated with your cognitive function affected by diet: brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). BDNF is essential in neuronal growth and survival as it protects neurons from damage triggered by the infection or injury. Meanwhile, it also associates with the consolidation of memory as it reinforces synaptic formation. NGF also plays a role in memory consolidation by affecting neuroplasticity and the survival of neurons in the forebrain (cerebral cortex, hippocampus (海马体), basal forebrain and hypothalamus (下丘脑)). These neurotrophic factors play a particular role in age-related diseases such as Alzheimer’s Disease (AD/阿尔兹海默症).
So, what are the foods that you are expected to eat?
The first type of antioxidative substance that we are going to talk about is flavonoid (类黄酮). It is a substance that can help promote your memory, learning and other cognitive functions. It has been discovered that flavonoids can increase the BDNF concentration in your hippocampus - a part of your brain that plays a vital role in long-term memory formation and consolidation. Where can you find flavonoids, then? Berries, including raspberry, strawberry, and blueberry, contain a high level of flavonoids (especially blueberry). Actually, chocolate also contains a lot of flavonoids. However, only dark chocolate that has higher than 70% of cacao is beneficial for your health.
Moving on to the next substance, curcumin (姜黄素), a natural polyphenol that can be found in the rhizome of Curcuma longa (turmeric, a spice). Curcumin boosts the release of a high level of BDNF in your brain. Through animal studies, scientists have discovered that curcumin has a function to delay or even reversing some brain diseases, including Alzheimer’s diseases (we should note that these studies were conducted in animals, so it is hard to say if the same effect will appear in humans). Eating curry to obtain curcumin will be one good way to increase your cognitive function.
The third one is vitamin E, a really common antioxidant substance, helps prevent the oxidation and causation of cognitive decline diseases (e.g., Alzheimer’s disease) by neutralizing free radicals. Foods containing a rich amount of vitamin E include almonds, sunflower seeds, avocados and spinach.
Other substances that are beneficial for improving your cognitive function are omega-3 unsaturated fatty acids (you can find it in oily fish such as salmon, sardine and herring), L-theanine (found in green tea) and resveratrol (found in grapes, nuts, blueberries, raspberry, etc.). There are many other foods that you can find to enhance your cognitive function. It is also essential for you to realize the idea of synergy when you are having the meal – foods associate together to contribute to your health – if you only consume vegetables and ignore other foods, such as meat and carbohydrates, it might cause you to suffer the deficiency in a specific molecule, and therefore increase the risk of having a particular disease. Besides eating, it is also necessary to obtain sufficient water every day. Ideally, getting around 500mL of water per day for every 13kg body weight would be enough. For the next article in this blog, I will write the foods that you may need to avoid eating to prevent risk increases the chance of having cognitive diseases.