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by Christian Maino Vieytes, Doctoral Student, Division of Nutritional Sciences, University of Illinois at Urbana-Champaign.

The Thinking and Non-Thinking Brain

 The Centers for Disease Control (CDC) defines a healthy brain as one with the ability to perform all functional mental processes such as the ability to learn, reason, use language, and remember.1 The brain is a marvelous organ. It is the only organ that consumes upwards of 25% of the body’s total energy needs, although it only accounts for 2% of the body’s mass.2 For every 100 calories of food that are consumed by an individual person, 20-25 of those calories are reserved exclusively for the brain! The brain is such a complex organ that neuroscientists are still scrambling to map out all connections between brain cells (called ‘neurons’), other brain cells, and bodily organs that make it up.

The functions of the brain are abundant. Your brain is not only responsible for conscious thought (in other words, what you think) but also for regulating the function of numerous other organs in the body underneath the guise of your conscious perception. Think about the last time you were aware of yourself breathing while you slept. You will find that this task is impossible. An area of the brain, known as the pre-Bötzinger complex, located in the brainstem is responsible for setting the pace and rhythm of your breathing while asleep and awake.3

Chronic Brain Disease Processes

 Like with any other organ system in the body, matters can go awry in the brain. Diseases involving the brain tend to be degenerative. That is, they tend to begin in the later-life stages and worsen with time. These changes are different and are more pronounced than the normal decline in memory and processing that come with aging. Two of the most common brain diseases are Alzheimer’s Disease and Parkinson’s Disease.

Alzheimer’s Disease is a type of non-reversible dementia that causes the brain to waste away, eventually to the point where normal and independent functioning is no longer possible. Parkinson’s Disease, on the other hand, involves the deterioration of the cerebellum, impacting motor function, and movements. Sadly, neither of these diseases has a cure. Nonetheless, recent research has uncovered potential ways to prevent these diseases from occurring in the first place.4

The risk factors for acquiring Alzheimer’s Disease, it has been found, are similar to those for diabetes and cardiovascular disease.5 Thus, maintaining a healthy weight and eating a diet rich in fruits and vegetables, which are rich in antioxidants, may prevent the onset of Alzheimer’s. Physical activity, especially during the middle-life years is associated with a decreased likelihood of succumbing to Alzheimer’s Disease.6 Critically, it is estimated that up to one-third of all Alzheimer’s cases are preventable thus signaling the urgency of communicating this information to the public.4


Omega-3 fatty acids are found in high concentrations in various algae and the fish that consume them.7 For decades, scientists have been touting the benefits of consuming fish for brain health. Indeed, the science substantiating these claims has become stronger over time and with more scientific evidence. It is estimated that the brain’s chemical composition comprises up to 50% of DHA, a type of omega-3 fatty acid.8 The effects of omega-3 fatty acids on brain health have been wide-ranging. In general, these effects are described as ‘maintaining cognitive function’ throughout the lifespan. Several research studies have highlighted how omega-3 consumption, either through ingestion of fish or an omega-3 supplement, may preserve processing speed, improve short-term memory, increase attention in children, develop reading ability in children, and stabilize moods and decrease anxiety.9


Omega-3 fatty acids and fish consumption may also protect against the onset of a stroke.10 A stroke is a severe cardiovascular condition that occurs when the blood supply to the brain is blocked or a blood vessel supplying the brain ruptures.11 Either of these events may have lasting and irreversible effects, such as paralysis or aphasia, which is the inability to produce language.12,13 A healthy diet and physical activity may prevent stroke. Both a Mediterranean-style diet and the Dietary Approaches to Stop Hypertension (DASH) diet have been associated with a decreased risk of having a severe and life-debilitating stroke.14

Another critical nutrient implicated in brain health and for preventing stroke is Vitamin B12. A deficiency in Vitamin B12 causes levels of a dangerous chemical to rise in the blood called homocysteine. High levels of homocysteine may cause a stroke.15 Vitamin B12 plays a role in converting homocysteine to a form, called methylmalonic acid, that is safe and not involved in promoting stroke. B12 is found primarily in animal-based products, though supplementation is a primary form of obtaining this crucial vitamin.16

The brain is a powerful organ that requires a substantial amount of nutrients and energy to function. To keep your brain healthy and running optimally, a nutritious diet, including one full of fruits, vegetables, and omega-3 fatty acids, is key. To learn more about keeping your brain healthy as you age, tune in to OneOp webinar by Dr. Olivia Okereke at



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