The idea that it is possible to better one’s health through a healthy diet may seem like a new notion, considering all the recent media reports on the topic. However, this hypothesis is nearly 2,500 years old, as evidenced by Hippocrates’ ancient advice to physicians to “leave your drugs in the chemist’s pot if you can heal the patient with food.” The fact that today’s emerging research has scientifically connected diet to disease prevention merely confirms what Hippocrates said way back then.
Although most of the studies to date have centered on the power of food to reduce cardiovascular disease and prevent cancer, diet can also have a profound effect on brain health. By nourishing your brain with the right foods, you can boost its levels of endurance, cerebration, acuity and cognizance, as well as its overall mental reserves. As we examine the latest research on protective brain foods, you will learn the best diet to support your brain’s functions, along with some sure-fire strategies to maintain your wit for a lifetime.
How Food Fuels the Brain
First, let’s take a look at that 3-pound mass of tissue we call our brain. The brain acts as the control tower for the body and the mind, containing as many nerve cells, or neurons, as there are stars in the Milky Way galaxy. Known as the primary functional units of the brain, these neurons “talk” to each other across fluid-filled junctions, or synapses, between the cells. These specialized delivery messengers are called neurotransmitters.
Neurons expend about 20% of the total energy consumed by the body each day (Raichle & Gusnard 2002), and nerve transmission across the synapses accounts for one-half of that expenditure (The Franklin Institute Online 2004). The neurons are continually firing as they gather and dispatch much-needed information to the rest of the body, while also coordinating the activities required to perform specific body needs. With all this activity, it’s no wonder that the brain is extremely active metabolically, making it hungry for fuel.
To support its high level of activity, the brain demands a continuous sugar fix. Glucose is its preferred energy source. Even while the body is at rest, the brain uses more than two-thirds of the carbohydrates circulating in the bloodstream (The Franklin Institute Online 2004). Consuming a diet rich in complex carbohydrates will provide a slow and steady release of energy, which is ideal for fueling a healthy brain.
Several studies have linked improvements in memory retention to a healthy diet, especially a sufficient intake of complex carbohydrate foods. One such study conducted at the University of Toronto compared a group of healthy seniors who ate a daily breakfast of a bowl of cereal, milk and a glass of white grape juice with a control group that only drank water for breakfast (The Franklin Institute Online 2004). Within 20 minutes of finishing breakfast, the cereal eaters scored 25% higher on memory recall and were able to remember more facts than the controls. It should be noted that the carbohydrates consumed in this study were complex in nature and thus able to sustain energy. Simple carbohydrates, on the other hand, are often low in nutrients and can actually upset the brain’s delicate energy balance by promoting short-term energy highs followed by extreme lows; this, in turn, often leads to lethargy and hunger.
In addition to supplying energy, dietary carbohydrate consumption has been shown to significantly impact mood and behavior via involvement in neurotransmitter action (Somer 1999). Suboptimal intake or a lack of carbohydrates in the diet can not only halt the brain’s main fuel supply but actually inhibit the creation of key neurotransmitters in the brain, potentially resulting in brain fog or mental confusion.
The Bottom Line: As a general guideline, most nutrition experts recommend that adults consume 45%-65% of their daily calories from complex carbohydrates to meet the brain’s unrelenting need for power.
Maintaining the Brain’s Transit System
While brain cells rely primarily on carbohydrates for energy, other tissues, enzymes and a variety of chemicals within the brain require protein for their structure and function. In fact, several key brain neurotransmitters depend on specific amino acids derived from protein-rich food sources in the diet. The balance of neurotransmitters in the brain plays an integral role in an individual’s mood, sleep patterns, cognition and overall brain performance. Many neurological diseases and mental brain disorders, such as Parkinson’s disease (PD), Alzheimer’s disease (AD) and attention-deficit disorder, are thought to be caused by imbalances in the brain’s neurotransmitters.
For example, individuals with PD typically exhibit characteristic symptoms of muscle rigidity and trembling hands, which can be attributed to the brain’s diminished ability to synthesize dopamine, the neurotransmitter associated with voluntary movement and fine motor coordination of the body. The amino acid needed for dopamine production is phenylalanine, found in foods such as almonds, eggs, meats and grains. Similarly, a lack of glutamate, the neurotransmitter associated with learning and memory, is thought to be linked to early memory malfunctions in AD, the most common form of dementia.
The Bottom Line: The good news is that it takes only two to three servings of quality protein intake each day to provide the nutritious mix of amino acids needed to help support healthy neurotransmitter function.
Chewing the Fat
Make no mistake about it: Growing and aging brains require the right amount of fat, which should come as no surprise considering that approximately two-thirds of the structural brain is made of fat (The Franklin Institute Online 2004). One way to improve your brain power is to consume the right dietary fats and oils to support cell membrane plasticity. Animal research has demonstrated a connection between the type and amount of fatty acid in the diet, the fatty composition of the brain cell membranes and the potential for positive impact on brain communication pathways (Yehuda et al. 1998).
In order for brain cells to function optimally, their membranes need to allow important molecules to cross through unimpeded. Therefore, the cell membranes need to be made up primarily of omega-3 fatty acids, not less healthy fats, like saturated fat, which tends to harden cell membranes.
The most abundant omega-3 fatty acid in the brain is docosahexaenoic acid (DHA), which constitutes a major component of the brain’s structural lipid membranes. DHA is an essential fatty acid and must be obtained through the diet. Including plentiful amounts of DHA in the diet has been shown to improve learning ability, whereas DHA deficiencies have been linked to learning deficits. Research has also linked low DHA levels in the brain to cognitive decline and incidences of AD. One study found that elderly people who ate fish once a week for 6 years developed 10% less cognitive decline than those who rarely or never ate fish; those who consumed fish two or more times weekly experienced a 13% reduction in cognitive decline (Morris et al. 2005a). Omega-3 fatty acids have also proved to be vital in promoting behavioral and cognitive functioning--by influencing emotional balance and positively affecting mood, for example (Somer 1999).
The Bottom Line: Make it your goal to get at least two 6-ounce servings of fatty fish—such as salmon, light tuna, pollack or catfish—in your weekly meal plan. But limit your intake of fish or shellfish that tend to have high mercury levels, such as shark, swordfish, king mackerel and tilefish.
Food on the Brain
It is never too late to get started on boosting your brain-building nutrients and mental reserves for a lifetime of better health and mental well-being.
“The most proactive thing that [people] can do to keep their brain in shape is to think overall health,” says Conrad Earnest, PhD, lead researcher and director of the Exercise Testing Core at Pennington Biomedical Research Center in Baton Rouge, Louisiana. “Focus on eating for a healthy heart, supplementing with B vitamins, maintaining an ideal weight, staying physically fit, minimizing stress and challenging the mind.”*
Look for part 2 of this article in the October issue of Inner IDEA Body-Mind-Spirit Review.
The Franklin Institute Online. 2004. The human brain. www.fi.edu/brain/carbs.htm; retrieved Jan. 1, 2007.
Morris, M.C., et al. 2005a. Fish consumption and cognitive decline with age in a large community study. Archives of Neurology, 62 (12), 1849-53.
Raichle, M.E., & Gusnard, D.A. 2002. Appraising the brain’s energy budget. Proceedings of the National Academy of Sciences of the United States of America, 99 (16), 10237-39.
Somer, E. 1999. Food & Mood: The Complete Guide to Eating Well and Feeling Your Best. Owl Books.