Intermittent Fasting: All You Need to Know
Intermittent fasting has gained a lot of traction in the health and wellness fields in recent years, yet you may ask how does it work? Does it really improve your health? And what’s the actual data? Well this piece will answer each of these questions.
Now firstly I can personally attest to the power of intermittent fasting.
For me it improved sleep quality, mitigated lethargy (especially the post-lunch lull) and finally shredded some stubborn belly fat that I couldn’t displace with even HIIT training.
But hey, for those of you who don’t know me, I’m just a guy on the internet, so why should you believe me?
Well, you don’t have to believe my anecdotal account so I’ll save that till later, and you can find actual studies on intermittent fasting below.
However, before I post links to the relevant studies, there’s a quick overview of what intermittent fasting actually is.
Intermittent Fasting: What is it?
Intermittent fasting generally falls into two key categories:
- Daily time-restricted eating, which narrows eating times from anything to 6-10 hours per day. Henceforth, your eating window maybe from 10am to 8pm, or if you’re feeling really ambitious, 11am to 5pm
- 5:2 intermittent fasting in which people limit themselves to one moderate-sized meal only two days each week
An array of animal and some human studies have shown that alternating between times of fasting and eating supports cellular health, probably by triggering an age-old adaptation to periods of food scarcity called metabolic switching.
Such a switch occurs when cells use up their stores of rapidly accessible, sugar-based fuel, and begin converting fat into energy in a slower metabolic process.
Intermittent fasting has arguably ridden the same wave of popularity as diets such as the paleo diet, which mimics our evolutionary ancestors diets in consuming only meat, fish and vegetables.
While intermittent fasting doesn’t specify what diet you should have (although it’s taken as read you’re eating healthily) it does follow the trend of an evolutionary basis in that our ancestors would often go for long periods without food.
The notion of 3 meals per day (with snacks in between) is actually very modern and not in sync with our evolutionary history.
Naturally, the argument so goes that intermittent fasting allows your body to find its natural rhythm, offering greater clarity, focus, physical and mental wellbeing, as well as energy.
Does Intermittent Fasting Work? What the Studies Say
Johns Hopkins Medicine neuroscientist Dr. Mark Mattson’s work has shown that intermittent fasting (IF) does work, and that it works well.
Mattson says studies have shown that IF improves blood sugar regulation, increases resistance to stress and suppresses inflammation.
In his research, Mattson notes that four studies in both animals and people found intermittent fasting also decreased blood pressure, blood lipid levels and resting heart rates.
More recently, preliminary studies suggest that intermittent fasting could benefit brain health too.
A multicenter clinical trial at the University of Toronto in April found that 220 healthy, non-obese adults who maintained a calorie-restricted diet for two years showed signs of improved memory in a battery of cognitive tests.
Mattson said: “We are at a transition point where we could soon consider adding information about intermittent fasting to medical school curricula alongside standard advice about healthy diets and exercise.”
IF Great for Shredding Fat & Blood Glucose Levels
In a small study now published in the journal Obesity, researchers from the University of Adelaide and the South Australian Health and Medical Research Institute (SAHMRI) assessed the effects of time-restricted eating (TRE) in 15 men for one week.
The blood glucose response to a standard meal was assessed each day of the study and the investigators found that intermittent fasting improved glucose control, regardless of when the men chose to stop eating.
In another study, researchers found that a 10-hour time-restricted eating window results in weight loss and reduced abdominal fat, as well as lower blood pressure and cholesterol.
The pilot study could lead to a new treatment option for metabolic syndrome, a condition affecting 30% of the US population, which can lead to diabetes, strokes and heart disease.
Study author and IF guru Satchidananda Panda said: “Unlike counting calories, time-restricted eating is a simple dietary intervention to incorporate, and we found that participants were able to keep the eating schedule.”
How Does Intermittent Fasting Work?
Researchers have discovered that IF helps people lose weight by lowering appetite rather than burning more calories, according to a new report.
The study is the first to show how meal timing affects 24-hour energy metabolism when food intake and meal frequency are matched.
“Coordinating meals with circadian rhythms, or your body’s internal clock, may be a powerful strategy for reducing appetite and improving metabolic health,” said Eric Ravussin, PhD, one of the study’s authors.
Lead author Courtney M. Peterson, PhD said: “We suspect that a majority of people may find meal timing strategies helpful for losing weight or to maintain their weight since these strategies naturally appear to curb appetite, which may help people eat less.”
Peterson and her colleagues also report that meal timing strategies may help people burn more fat on average during a 24-hour period.
Early Time-Restricted Feeding (eTRF) – a form of daily intermittent fasting where dinner is eaten in the afternoon – helped to improve people’s ability to switch between burning carbohydrates for energy to burning fat for energy, an aspect of metabolism known as metabolic flexibility.
How About Extended Fasting?
If you’ve been convinced by intermittent fasting, you may want to try prolonged fast which has excellent results in detoxing the body and mind.
To review my first 36-hour water fast, check out the below video: