What You Need To Know About Intermittent Fasting

“Fasting! That sounds great!” [sarcastic, but still supportive, if that’s possible] was my response, when my husband told me he was planning to begin this, at the time, somewhat novel dietary approach.

At that time, only a few years ago, the only people we knew who fasted regularly were friends who observed for Lent or Ramadan, but it is now on the verge of becoming (if not already) a health fad.

Since that first, (supportive) conversation, I have also begun practicing intermittent fasting, and believe I am now a convert!

Intermittent fasting (“IF” from here on in) is precisely what the name implies, “fasting, but not continuously”. There are different approaches to IF. Essentially, anything goes, as long as fasting periods are at least approximately 16 hours duration.

Popular protocols are the “Warrior Diet” in which all daily eating is done in a four-hour window, leaving 20 hours for fasting; “alternate day fasting” (sometimes referred to as “5:2” fasting), in which eating is confined to 12 hours daily (e.g., between 8:00 AM and PM) for five days weekly, and an all-day fast is performed two, non-consecutive days (e.g., Tuesday and Thursday) weekly; and what we practice, eating all our meals within an eight-hour window daily (in our case, between 11:00 AM and 7:00 PM). During the fasting period, it is okay to drink water, black coffee or espresso.

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My husband began experimenting with fasting, partially because he is a naturopathic doctor and professionally he wanted to experience fasting; but mainly it made sense for him because after our children were born, he was becoming a “skinny fat guy”, outwardly appearing thin, but thicker and softer in the middle, and with increasing (though not yet worrisome) blood lipids (e.g., cholesterol levels).

Fasting increases fat burning, and decreased body fat levels are associated with improved blood lipid levels, blood sugar control, heart health and a slimmer appearance (which, presumably, is why so much online fasting information is found on sites more directed at vanity than health).

• Weight Loss
• Decreased body-fat percentage
• Decreased waist circumference
• Improved appetite control
• Decreased “bad” cholesterol and blood triglycerides
• Decreased systemic inflammation (measured using blood markers for inflammation, e.g., c-reactive protein)
• Improved blood-sugar control
• Deceased blood pressure
• Decreased cancer risk
• Increased rates of cellular repair
• Improved memory and learning
• Increased lifespan

Some truly remarkable health benefits occur with periods of fasting longer than those discussed here, and outside the scope of this post. Fasting for periods of at least two-days triggers cellular regeneration, and fasting for periods of three-days promotes regeneration of myelin, the tissue that suffers autoimmune damage in multiple sclerosis.

Many of the benefits of IF are associated with fat loss. Fasting essentially gives your body an opportunity to burn fat for fuel.

Your body is constantly burning calories in the form of sugars (glucose) to stay alive. In order to provide tissues with the sugar needed, your liver and muscles store glucose as “glycogen”, enough for about 12 to 14 hours (unless intensely exercising). After this source of fuel is depleted, assuming no carbohydrates are consumed to replenish stores, the body begins to metabolize (“burn”) fat for fuel.

Less than you may think. In fact, our own experience has been that it actually streamlines our day.

Research demonstrates that although fasting and caloric restriction (“dieting”) are equally beneficial for weight loss, improving insulin sensitivity and other health biomarkers; fasting is simpler to organize, and easier because it reduces appetite, while caloric restrictions does not (in fact, people who reduce calories by constant restriction/dieting, experience constant hunger).

First off, to be clear, IF is not a short-cut. It is not simply “not eating” (that’s called starving yourself, and is not a health practice).

Although fairly simple, I consider IF somewhat “advanced eating” and I suggest if you are a new to this topic, speak to a health professional before starting.

Fasting is mildly stressful for your body, imposing a mild stress on cells. This is one of the proposed mechanisms for the physiological benefits it yields. It follows that you should be eating nourishing food to allow your body the nutrients it requires to endure the stress you are imposing on it. We follow a sort-of paleo/keto hybrid guideline, but a simple, well-balanced diet is adequate, and in fact, likely superior to the diet most subjects in human fasting research eat.

The IF approach we use is to fast almost every day (we aren’t too strict on weekends), overnight (eight hours we would not be eating anyway). We stop eating after dinner (around 7:00 PM) and have our first meal of the day at around 11:00 AM.

1. It allows our bodies approximately two to four hours of fat-burning daily
2. Compared to other IF approaches, it is easier to create a routine (same eating pattern, every day)
3. It is easy to integrate into a routine. Dieting usually requires the learning of new recipes for each meal, adding responsibilities to peoples already busy schedules
4. It allows us to avoid a meal that is typically “starchy” in nature (which is inconsistent with our overall paleo/keto eating approach)
5. It eliminates the option of late night snacking, which is for most will not be a nutritious food (“Let’s crack open a bag of baby carrots and watch Netflix”, said no one ever), and contributes to weight gain, high cholesterol and blood-sugar, and liver damage
6. Practically, it likely (we haven’t measured), allows us to reduce our daily caloric intake
7. IF is not focused on reducing daily calorie intake, but rather restricting it to a particular, in this case eight-hour, time window. That said, research suggests caloric restriction of approximately 30% both delays onset of chronic diseases of aging and prolongs lifespan
8. Neither of us is particularly hungry in the morning, which makes it easy

We enjoy espresso about an hour after the kids are off to school, about 90-minutes after waking, which we find takes the edge off if we do happen to notice hunger. (FYI: Research generally does not support an appetite-suppressing action for caffeine, but it works for us).

Like all things, IF is fairly straightforward, but it isn’t for everyone.

• Eat a poor diet (IF is not a “weight loss hack”)
• Have a personal medical history of having an eating disorder
• Sleep poorly
• Are “depleted” or “worn down”
• Are a woman having hormonal imbalance
• Exercise intensely
• Are not well-versed in nutrition and cooking (without professional guidance)
• Are pregnant or breastfeeding

Ultimately, it's important to determine what diet works best for you! But most importantly, if you're looking to pursue IF, I would recommend speaking to a natural health care practitioner first.

Have you tried Intermittent Fasting? What has your experience been like?

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