The first time Rahul Jandial opened the skull of a living human being as a third-year medical resident at the University of California, San Diego, he knew he'd found his calling.
"There's a fear, of course, but also awe that you're literally inside somebody's head, which elicits intensity as well as excitement. I don't want to sound indelicate, but for me, it's a thrill," Jandial says.
But you don't have to be a neurosurgeon to be fascinated by the brain. Everyone from Silicon Valley tycoons to biohackers are dabbling in cognitive performance enhancers known as nootropics, which tout improved cognition by a drop of a pill.
And that's what worries brain surgeon Jandial, who calls the "smart" pills being peddled and much of the advice being doled out unproven "nonsense."
In fact, it inspired Jandial to write a book with science-backed advice on how to achieve optimal brain performance.
"I've known students in my medical school classes who thought they get better grades by taking 'smart' pills, which in truth only allowed them to work longer and harder at being just as stellar or mediocre as they were to begin with," Jandial, a dual-trained brain surgeon and neuroscientist at City of Hope in Duarte, California writes in his new book, "Neurofitness: A Brain Surgeon's Secrets to Boost Performance and Unleash Creativity."
Jandial tells CNBC Make It that the best ways to boost brain power for peak performance are actually easier than people think. Here are his top three:
Intermittent fasting may be trendy, but fasting is nothing new: Several of the world's major religions call for periodic fasting, and Jandial thinks that might have to do with how it affects the brain. Research has shown that fasting can help to clear the mind and awaken the senses while also boosting brain functioning.
Two days a week, Jandial himself practices intermittent fasting — where you eat normally for eight hours a day, from 9 a.m to 5 p.m. for example, and then eat nothing except to drink water, coffee or plain tea for the other 16 hours — to boost his cognitive performance.
Going without food for 16 hours (which can include the time you're sleeping), increases your brain's natural growth factors, he says, which essentially support the survival and growth of your brain's neurons. The neurons are what allow information to be transmitted between areas of the brain and the rest of the body's nervous system. So if your neurons are healthy and operating at full capacity, information will be transmitted faster and more clearly, he says, meaning you will be more focused and be able to obtain and store information more easily, improving cognitive performance.
Other research from John Hopkins has also found that intermittent fasting may help your "brain ward off neurodegenerative diseases like Alzheimer's and Parkinson's while at the same improving memory and mood."
Jandial says an easy trick to help get 16 hours is to skip breakfast (which he actually does every day). Though breakfast has been dubbed the most important meal of the day, he says there is no evidence to support that theory.
He himself practices 16-hour intermittent fasting on Mondays and Thursdays (to do non-consecutive days), skipping both breakfast and lunch and eating all his daily calories for dinner. He says while he sticks to the MIND diet (which consists of whole foods like fruit, vegetables, whole grains, beans, and nuts—as well as fish and some poultry) for brain benefits, "it doesn't matter how much you eat or what you eat."
However, Jandial suggests individuals consult with their own doctor before trying any fast. Experts advise against some people, including the elderly, pregnant women and children, doing any type of fasting. And they caution there are risks with extreme fasts and fasting that lasts longer than 24 hours.
To calm the mind before heading into a stressful work or life situation, Jandial suggests doing five minutes of slow, deep breathing.
"Before you have to go see your boss or before you pull into that parking spot at work, just find a place to slowly breathe in through your nose for a count of four, and then hold your breathe for a few seconds and then exhale slowly through your mouth for a count of four," he says.
Doing this "meditative breathing" two times a day will help calm the neurons in your brain, he says, which will also help your thoughts be "faster, quicker, and more original," and he adds that this is typically when a person's peak performance comes in.
Mindful breathing's brain-boosting powers are backed up by research: A study at the University of Oregon found that just 11 days of mindful breathing for an hour each day through a technique called integrative body-mind training (IBMT) "induces positive structural changes in brain connectivity by boosting efficiency in a part of the brain that helps a person regulate behavior in accordance with their goals." Jandial adds that improved connectivity across different corners of your brain is directly involved in decision-making, impulse control and focus.
Stand or walk as much as possible at work, says Jandial.
"The brain is meant to be on a vertical body and when a person is standing or walking, the brain showers itself with BDNF (brain-derived neurotrophic factor, essentially a protein for the brain). BDNF is not a hormone like estrogen, it's a growth factor. It's like miracle grow for the flesh of the brain," he says.
Your brain thrives off these growth factors, according to Jandial, because they help to maintain the health of the 90 billion neurons humans have in our skulls, which ultimately improves the electrical communications between them and therefore brain performance.
He says by being vertical, you are essentially giving yourself a brain drug like a nootropics without taking a pill or supplement.
"Most people don't realize that they already have the right 'brain drugs' inside them to help perform better," he says.
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