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How does the brain use food as energy?

  • Published21 Dec 2012
  • Reviewed21 Dec 2012
  • Author Fernando Gomez-Pinilla
  • Source BrainFacts/SfN

The brain is an energy-hungry organ. Despite comprising only 2 percent of the body’s weight, the brain gobbles up more than 20 percent of daily energy intake. Because the brain demands such high amounts of energy, the foods we consume greatly affect brain function, including everything from learning and memory to emotions.

Just like other cells in the body, brain cells use a form of sugar called glucose to fuel cellular activities. This energy comes from the foods we consume daily and is regularly delivered to brain cells (called neurons) through the blood. 

Studies suggest the quality of the foods consumed over the lifetime affects the structure and function of the brain. For instance, the consumption of omega-3 fatty acids found in fish provides structural material to maintain neurons. Studies also suggest omega-3 fatty acids are essential for the transmission of information between brain cells. In contrast, foods that are rich in sugars and saturated fats have been found to promote oxidative stress, which leads to damage of cell membranes. 

The food you eat also affects molecules in the brain that support cognition. Some foods, such as those with turmeric, support cognition by helping to maintain molecular events related to energy metabolism.

Recent studies suggest lifestyle choices that affect the metabolism of nerve cells, such as diet and exercise, may in some cases provide a noninvasive and effective strategy to counteract neurological and cognitive disorders.

Gomez-Pinilla F. The combined effects of exercise and foods in preventing neurological and cognitive disorders. Prev Med. 52 Suppl 1:S75-80 (2011).

Gomez-Pinilla F. Brain foods: the effects of nutrients on brain function. Nat Rev Neurosci. 9(7):568-78 (2008).

Gomez-Pinilla F., Yizng Z., Roy R.R., et al. Voluntary exercise induces a BDNF-mediated mechanism that promotes neuroplasticity. J Neurophysiol. 88(5): 2187-95 (2002).

Vaynman S., Ying Z., Gomez-Pinilla F. Interplay between brain-derived neurotrophic factor and signal transduction modulators in the regulation of the effects of exercise on synaptic-plasticity. Neuroscience. 122(3): 647-57 (2003).

Wu A, Ying Z., Gomez-Pinilla F. Omega-3 fatty acids supplementation restores mechanisms that maintain brain homeostasis in traumatic brain injury. J Neurotrauma. 24(10):1587-95 (2007).
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