Study Shows Why Fasting Is Just as Important as What You Eat

tudy Reveals How the Liver Responds to Food So Quickly_woman eating

Did you know that just minutes after you eat a meal, your bloodstream is flooded with nutrients and your body undergoes a monumental shift from a fasting- to feeding-state to break down and store fats and sugars? That’s right, within half an hour, your liver switches completely from burning stored fat for energy to stockpiling sugar, or glucose. The sheer speed of this metabolic transformation befuddled scientists, until now. They knew the liver’s cells couldn’t possibly activate genes and produce RNA blueprints to create new metabolic proteins in that timeframe, so how does the liver respond to food so quickly? In a new study[ref url=””], Salk Institute for Biological Studies researchers found the answer – liver cells actually store pre-RNA molecules that are instrumental in glucose and fat metabolism.

Liver cells store pre-RNA molecules called NONO that are key to glucose and fat metabolism

Scientists have known that an RNA-binding protein called NONO regulated daily circadian rhythms in the body. However, this study’s researchers wondered if NONO also had a specific role in the liver, so they decided to analyze NONO levels in response to feeding and fasting in mice. Post-feed, NONO clumps suddenly appeared in the mice liver cells, and they were bound to RNA molecules. Sure enough, within half an hour, the levels of proteins that corresponded with the NONO-RNA molecules increased.

“After mice eat, it looks as if NONO brings all these RNAs together and processes them so they can be used to make proteins,” says Satchidananda Panda, a professor in the Salk Institute’s Regulatory Biology Laboratory and lead author of the paper.

Understanding the role of NONO in metabolism could lead to new therapies for obesity and diabetes

Without NONO, it took more than three hours for protein levels (those involved in processing glucose) to rise. During those three hours, blood glucose spiked to unstable levels. What this means for those with diabetes who possess high blood glucose levels is that mice without NONO may be a potential disease model to study. “Understanding how glucose storage and fat burning are regulated at the molecular level will be important for the development of new therapies against obesity and diabetes,” says first author Giorgia Benegiamo.

In the meantime, what is clear: “The switch from fasting to feeding is a very quick switch and our physiology has to adapt to it in the right time frame,” says Satchidananda Panda. “Now we know how our body quickly handles that extra rush of sugar.”

Be mindful of your peas…and avocados

So why does this study mean for you? Everything you eat matters and causes a unique response in your body — even something as minuscule as a leftover goldfish from your child’s lunchbox. So it’s important to be mindful of how — and how often — you fuel yourself. (If you want to dive deep into Bulletproof-friendly foods, check out the Bulletproof Diet Roadmap.)

Balance your feeding-state with a healthy fasting-state

As this study reveals, your fasting state is just as critical to metabolism as your feeding state. That’s where intermittent fasting comes in. The idea behind intermittent fasting is to consume all of your daily food in a shortened time period (say, a six-hour window) and fast for the remaining part of the day/night. This study[ref url=””] demonstrates that intermittent fasting reduced blood sugar and insulin levels and increased neurons’ resistance to excitotoxic stress in mice. Think of it this way – intermittent fasting, combined with Bulletproof eating,  boosts the body’s energy production, reduces cholesterol, lowers inflammation, and helps you lose weight[ref url=”″].

When done the Bulletproof way, intermittent fasting isn’t as tough as it sounds. Get the scoop on how to get started with intermittent fasting here. The key difference between standard intermittent fasting and Bulletproof intermittent fasting: You get to drink coffee with grass-fed butter in the morning before you break your fast at lunchtime. The creamy concoction fills you up and keeps you from feeling deprived. If you’re a woman, you may have different needs when it comes to intermittent fasting. Read up on Bulletproof intermittent fasting for women here.

Related: How To Lose 75 Pounds in 75 Days with Bulletproof Intermittent Fasting





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