Intermittent fasting (specifically the 5:2 diet) became popular in the UK in 2012[14][15][16] after the BBC2 television Horizon documentary Eat, Fast and Live Longer.[17] Via sales of best-selling books, it became widely practiced.[18][19] In the United States, intermittent fasting has become a trend among Silicon Valley companies.[20] According to NHS Choices as of 2012, people considering the 5:2 diet should first consult a physician, as fasting can sometimes be unsafe.[18][21] A news item in the Canadian Medical Association Journal expressed concern that promotional material for the diet showed people eating high-calorie food, such as hamburgers and chips, and that this could encourage binge eating since the implication was that "if you fast two days a week, you can devour as much junk as your gullet can swallow during the remaining five days".[22]
One thing to consider about bone broth that sets it apart from plant foods: Even if you do eat a variety of plants that contain collagen-boosting nutrients, if you have a weakened digestive system, you may not fully absorb them. On the other hand, the collagen in bone broth is incredibly easy to absorb, even for those with compromised digestive systems.
Forms of intermittent fasting exist in religious practices in various groups across the world.[12] Religious fasting regimens include, but are not limited to, Vrata in Hinduism, Ramadan fasting (Islam), Yom Kippur fasting (Judaism), Orthodox Christian fasting, Fast Sunday (The Church of Jesus Christ of Latter-day Saints), and Buddhist fasting.[12] Certain religious fasting practices, like Buddhist fasting, only require abstinence from certain foods, while others, like the Jewish fast on Yom Kippur, last for a short period of time and would cause negligible effects on the body.[12]

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You’ll run out of energy. When you don’t have anything in your system for several hours, your blood sugar will eventually drop below baseline. If you’ve ever had a blood sugar crash, you know how this state feels. Sleepiness, trouble focusing, lightheadedness, intense cravings, and the occasional mood swing typically accompany low blood sugar. Your cells run low on fuel and they start demanding that you give them more carbs.[13]


Following what Greg lays out for us, we should wait a couple of hours and stave off our cup of jolt, kick-starter for at least a couple of hours after getting up. Instead, we should have some hydrating water. That’s a hard one, let’s be truthful. Real hard, especially for coffee lovers, but I suppose there is a reason for this. I think this has something to do with cortisol levels. This really helps when, or if you get hunger pains and then have a cup of wakey juice or two or three or four cups. This almost always alleviates the hunger, so this is why it’s so powerful.
The problem is that we tend to spend so much time in the fed state, fueling our bodies exclusively with glucose, that we become addicted. Once the flow of glucose stops and our insulin levels drop, we start getting hunger pains. This is one of the reasons that overweight individuals — people with more than adequate energy stores in their fat cells — often have such a difficult time cutting back on food intake. They’re not starving, but they’re not getting the glucose their bodies are used to.
Following what Greg lays out for us, we should wait a couple of hours and stave off our cup of jolt, kick-starter for at least a couple of hours after getting up. Instead, we should have some hydrating water. That’s a hard one, let’s be truthful. Real hard, especially for coffee lovers, but I suppose there is a reason for this. I think this has something to do with cortisol levels. This really helps when, or if you get hunger pains and then have a cup of wakey juice or two or three or four cups. This almost always alleviates the hunger, so this is why it’s so powerful.

Fasting helps you build a better brain, too. Intermittent fasting increases a protein in your brain called BDNF that researchers have nicknamed “Miracle-Gro for your brain.”[7] BDNF improves learning and memory and can help you forge stronger neural pathways, making your brain run faster and more efficiently, which is especially important as you age.
Fill your plate with plenty of healthy fats, such as coconut oil, avocados, olive oil, ghee and grass-fed butter as well as moderate amounts of protein foods like grass-fed meat, free-range poultry, fatty fish and eggs. Non-starchy vegetables, fresh herbs, nuts, seeds and healthy beverages like water, bone broth and green tea can all be enjoyed as well.
This is a new area, but the research that has come out since this article is also positive, and promising. One example: In this June 2018 study of 23 people with obesity, 12 weeks of 8-hour time-restricted feeding resulted a 2.6% decrease in body weight and a 7 point decrease in systolic blood pressure, which was significant when compared to controls: https://www.ncbi.nlm.nih.gov/pubmed/29951594
The biggest concern most people have is that Intermittent Fasting will lead to lower energy, focus, and the “holy crap I am hungry” feeling during the fasting period and ruin them. People are concerned that they will spend all morning being miserable because they haven’t consumed any food, and thus will be miserable at work and ineffective at whatever task it is they are working on.
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