How intermittent fasting changes your brain
A new study from Singapore found that intermittent fasting increases neurogenesis.
- Rats that fasted for 16 hours a day showed the greatest increase in hippocampal neurogenesis.
- If true in humans, intermittent fasting could be a method for fighting off dementia as you age.
- Intermittent fasting has previously been shown to have positive effects on your liver, immune system, heart, and brain, as well as your body's ability to fight cancer.
Intermittent fasting (IF) is not new. Many religious traditions, including Hinduism, Islam, Buddhism, and Orthodox Christianity have practiced forms of it. These methods were predominantly due to food shortages or spiritual pursuits. Today IF is most often promoted as a weight-loss regimen, and there is some evidence that it is useful in that capacity. One extensive review found that it not only helps with obesity, but also hypertension, inflammation, and insulin resistance.
Proponents swear by its efficacy. In reality, intermittent fasting is just about closing your feeding window: don't eat first thing in the morning (or breakfast at all), don't eat for two hours (or longer) before bed. It's a practical approach to eating, yet, as with everything in our time, it has to be packaged and marketed to be sold as a lifestyle. That's not to say that IF isn't effective. It's just not miraculous.
One honest debate that has persisted for years is how long to fast for. Twelve hours? Sixteen? Twenty? A new study, published in the journal Brain and Behavior, set out to answer this question with a specific goal in mind: how does intermittent fasting affect neurogenesis?
While neurogenesis is most active in embryos, neuron creation is possible throughout life. The more you can achieve this as you age, the better, especially in areas like your brain's hippocampus—the focus of this study. The main duties of the hippocampus is the consolidation of experiences and information as you store short-term memories as long-term memories and spatial navigation, which is another form of memory. In Alzheimer's disease, your hippocampus is usually the first brain region to suffer.
For this study, three groups of rats were tested, with a fourth control group receiving no eating restrictions. One group fasted for 12 hours, another for 16, and the final group fasted for 24 hours (on the second day they ate without restriction as well). All groups were given the same number of calories.
The three restricted groups all fared better in terms of hippocampal neurogenesis than the control group. Interestingly, the 16-hour group performed best, especially when tested for increased activation of the Notch signaling pathway—specifically, the NOTCH1 pathway (mammals have four). This pathway is implicated in the brain's ability to form new neuronal connections. This process allows us to form new memories, which is one reason why hippocampal neurogenesis helps to keep dementia at bay.
The study adds another piece to the puzzle of how diet—specifically in this case, when you eat—affects cognitive health. Judging by these results, it appears that restricting your feeding window to eight hours a day can have profound effects.
The benefits do not stop with neurogenesis. As the Singapore-based team writes,
"Prophylactic IF has been shown to promote longevity as well as ameliorate the development and manifestation of age‐related diseases such as cardiovascular, neurodegenerative, and metabolic diseases in many animal studies. It has also been postulated that IF is able to cause changes in the metabolic pathways in the brain, which leads to stress resistance capacity of brain cells."
This follows up previous research that found intermittent fasting has positive effects on the liver, immune system, heart, and brain, as well as the body's ability to fight cancer. While specifics, such as fasting duration and caloric load, remain to be seen—most likely, those will have to be decided on an individual basis—this is another win for the IF crowd. Closing your feeding window appears to have many beneficial effects for overall health.
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To create wiser adults, add empathy to the school curriculum.
- Stories are at the heart of learning, writes Cleary Vaughan-Lee, Executive Director for the Global Oneness Project. They have always challenged us to think beyond ourselves, expanding our experience and revealing deep truths.
- Vaughan-Lee explains 6 ways that storytelling can foster empathy and deliver powerful learning experiences.
- Global Oneness Project is a free library of stories—containing short documentaries, photo essays, and essays—that each contain a companion lesson plan and learning activities for students so they can expand their experience of the world.
We’re about to kick off the sixth great extinction event. And we’ll follow shortly after.
Like any other system, capitalism has its positive and negative qualities. Inarguably, it has lifted nearly a billion across the globe out of extreme poverty, between 1990 and 2010. But as with other socioeconomic systems of the past, such as with feudalism, a time can come when revolutionary changes make such systems anachronistic. So too has capitalism’s time come, at least the kind which exploits the biosphere.
The future of education and work will rely on teaching students deeper problem-solving skills.
- Asking kids 'What do you want to be when you grow up?' is a question that used to make sense, says Jaime Casap. But it not longer does; the nature of automation and artificial intelligence means future jobs are likely to shift and reform many times over.
- Instead, educators should foster a culture of problem solving. Ask children: What problem do you want to solve? And what talents or passions do you have that can be the avenues by which you solve it?
- "[T]he future of education starts on Monday and then Tuesday and then Wednesday and it's constant and consistent and it's always growing, always improving, and if we create that culture I think that would bring us a long way," Casap says.
These Jurassic predators resorted to cannibalism when hit with hard times, according to a deliciously rare discovery.
- Rare fossil evidence of dinosaur cannibalism among the Allosaurus has been discovered.
- Scientists analyzed dinosaur bones found in the Mygatt-Moore Quarry in western Colorado, paying special attention to bite marks that were present on 2,368 of the bones.
- It's likely that the predatory carnivore only ate their already-dead peers during times when resources were scarce.
As a doctor, I am reminded every day of the fragility of the human body, how closely mortality lurks just around the corner.