Researchers have found that intermittent fasting may enable you to have more brain energy, better memory, and better learning abilities.
How does fasting help us give our brains more energy?
Humans—and, indeed, all other living things on Earth—need sustenance. Willingly choosing to abstain from eating for health reasons thus seems counterintuitive. However, findings show that fasting isn’t necessarily an entirely negative experience for our bodies. In fact, fasting every now and then may even give our brain more energy, as well as stave off cardiovascular and age-related diseases.
From an evolutionary perspective, it makes sense. Humans didn’t always have continuous access to food sources (something that, unfortunately, is still a reality for many people across the globe today). Thus, our ancestors had to still be able to function mentally on an empty stomach. Studies involving mice have found links between intermittent fasting and decreasing damage in the cells, but mice are mice and humans are humans. There is therefore a need for similar studies involving humans instead of mice.
That’s what Mark Mattson and his colleagues are trying to do.
The protein brain-derived neuropathic factor can lead to more connections among brain cells.
In intermittent fasting, the body switches energy sources from glucose to fat cells. According to the research findings, fat cells stimulate brain activity and growth. Glucose, meanwhile, comes from the liver. Our liver energy stores can run for 10 to 14 hours, after which our bodies switch to our fat stores. These fat stores are then converted to ketones, which are found in the blood.
“Ketones act directly on the nerve cells to stimulate production of BDNF and may help optimize cognition, learning and memory building,” said Mattson. BDNF, or brain-derived neurotrophic factor, is a protein involved in learning and may be what’s driving brain cell growth. BDNF levels tend to decline as we grow older, especially in people who have been diagnosed with conditions that affect cognitive functions. In fasting mice, however, BDNF levels rose by 50 percent, leading to a week or two of better mental function.
Would eating less have the same effect? Apparently not. 'People who eat three meals a day but have an overall relatively low calorie intake - between 1,800 and 2,000 every time they eat a meal - replenish their liver energy stores,” Mattson says. “So they may go six hours between meals, but that's not enough to elevate ketones.”
Two days of fasting may be the key to boosting brain energy.
Mattson thinks that in theory, BDNF may be stimulating cells to produce more mitochondria. Mitochondria, known as the powerhouse of the cell, are what transform chemicals into the form of energy usable to cells. It’s possible that the more mitochondria there are, the more that brain cells are able to make connections with each other.
There is already a clinical trial studying how fasting affects the brains of older women. The participants in the study have been asked to eat as normal for five days, then severely restrict their food intake for two days afterward. This is often called the 5:2 diet.
Mattson also thinks that this diet may be able to fight cancer. Our bodies might be able to find an alternative fuel source to sugar, while cancer cells might not. Thus, fasting may starve the cancer cells out. Of course, more studies are necessary to back these claims.
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