Lately, there's been a lot of hype around intermittent fasting. But is it really a healthy choice for everyone

Following popular fashion trends may catapult you from drab to fab, but when it comes to nutrition, the latest fads aren't always what's best for your body or lifestyle. Because intermittent fasting has been one of the most "trendy" weight-loss conversations of 2020, we decided to dig a little deeper. Here's what we found!

What is intermittent fasting?

Intermittent fasting is an eating pattern that cycles between periods of fasting (not eating) and eating. Unlike other fad diets, intermittent fasting doesn't specify what you can eat, but when you should eat. Here are two of the most popular variations in which people practice intermittent fasting:

  • Daily intermittent fasting: Some choose to make it a part of their everyday lifestyle by fasting for 14-16 hours between dinner and breakfast the next day. (They aim to eat all of their meals within a 6-8 hour time frame).
  • Weekly intermittent fasting: Others follow a weekly schedule where they eat normally 5 to 6 days a week and fast 1 to 2 days. (During their fast periods they don't eat at all OR they refrain from eating for 16+ hours and restrict their calories to 500-600 on fasting days.)

The basis of intermittent fasting is that if we let our insulin levels dip down far enough, for long enough, we begin to burn fat.

Here's a quick breakdown of the glucose/insulin process:

  1. When we eat, our bodies convert carbohydrates (found in grains, vegetables, fruit and milk) into a simple sugar called glucose.
  2. Glucose is absorbed from our gut into our bloodstream. (Do the terms "blood sugar" or "blood glucose levels" sound familiar? Many of us have had our blood glucose levels tested before.)
  3. Once absorbed, our bodies immediately start working to process glucose by releasing insulin (a regulatory hormone). Insulin either helps use the sugar for energy or store it in our fat cells (as fat) for future use.
  4. Our fat cells release this stored sugar when our insulin levels are low and our bodies need more energy (between meals, as long as we're not snacking, or during physical activity).
  5. When we eat more calories than our body needs, we build up excess fat cells, which results in weight gain.

In short, people often gain weight because they don't allow their body ample time to burn its stored food energy before replenishing with more food. This is why it's so important to eat healthy, well-rounded meals (yes, that includes portion control) that are spaced out (limit your in-between snacking!) and supplemented with exercise.

Obesity, diabetes and cancer

It's no secret that being overweight, or obese, greatly increases the risk of developing type 2 diabetes. So, it makes complete sense that burning that excess stored fat (through any means, not just intermittent fasting) will minimize the risk of diabetes.

Cancer has also been linked to obesity, but not because obesity itself causes the cancer. If the genetic mutation (cancer cells) are already present, high levels of insulin (often found in overweight or obese individuals) can stimulate these cancer cells to grow faster.

So, could intermittent fasting help reduce the risk of diabetes and cancer? In theory, yes. However, this is largely due to the fact that fasting reduces extremely high levels of insulin growth in overweight and obese individuals. Those with a healthy BMI, and therefore healthy levels of insulin, would likely not reduce their already low risk any further due to fasting.

The hunter-gatherer

Because our ancestors were hunter-gatherers, without modern day conveniences like the grocery store or local smoothie joint, fasting has been a key to our survival from the beginning. But that doesn't necessarily mean it's always beneficial or that it's for everyone.

Even though it's been around since the beginning of time, the benefits and adverse side effects of intermittent fasting vary and are still under research. Here are some of the known pros and cons:

Pros

  • Doesn't cost anything, unlike other diets
  • No food specifics - meaning you can eat whatever you want during the allowed time frame (this can be seen as a pro or a con, but let's face it, who doesn't like dietary freedom?)
  • Can reduce your daily caloric intake (if you're following portion control and eating healthy, whole foods)
  • Encourages the body to use stored fat for energy (burning off excess fat)
  • Can create a more focused outlook and improve mental clarity
  • Can help with weight loss and possibly help prevent diabetes

Cons

  • Hard to manage long term
  • May not support our body's metabolic and hormonal systems
  • Some people resort to overeating or eating processed foods in their allowed eating period because they are so hungry
  • Can be inconvenient, depending on your schedule and lifestyle
  • Can increase your cortisol (stress hormone) levels
  • Food is fuel, so if you intensely exercise while fasting it could lead to an energy deficit (think weak, light-headed, passing out, not thinking clearly...)
  • Can exacerbate already unhealthy relationships with food (emotional or overeating)
  • May experience headaches and irritability

What to know before you try it?

  • You should always talk to your doctor before drastically changing your diet
  • Consider how intermittent fasting may not be compatible with certain medications you're taking
  • Keep in mind what you can manage long term (think realistic and sustainable)

What's the right way to eat?

Nightly eating. To find what works best for our own bodies and lifestyles, we've tried a lot of different approaches over the years. Because we have a relatively healthy relationship with food, we prefer not to incorporate any of the more demanding intermittent fasting options. Instead, we like a less-strict, normal nightly fast that involves not eating dinner or snacking after 8:00 pm.

Brekki. We eat in the morning somewhere between 6:00 and 9:00 am, depending on our schedules. If we're working from home and have the ability to eat a healthy breakfast later in the morning, we do. If we have to run out the door and head into a meeting until noon, we eat first thing.

We feel that a healthy breakfast is essential because it gives our body much-needed nutrients to rev up our metabolism and curb hunger cravings throughout the day. When we've followed a strict intermittent fasting routine and skipped breakfast in the past, we've had an increased appetite, a drop in energy and made poorer choices throughout the day (hello, uncontrollable cravings).

Rather than a strict schedule that doesn't allow us to eat between 8:00 pm and 10:00 am, we base our timing more realistically around our schedules and when we can make healthy choices.

Low carb. In addition to our "no eating after 8:00 pm" rule and morning breakfast routine, we tend to eat a low-carb (NOT no-carb!) diet. When eating carbs, we try and find them in their purest form (whole foods and grains) so they release energy slowly throughout the day, rather than refined carbs (such as white bread, pasta and crackers) that create short bursts of energy and contribute to unstable blood sugar levels.

This has been a more realistic, sustainable and effective approach for us.

Let's recap a few of the big takeaways:

  1. Avoid highly processed foods (especially refined carbs such as white bread, crackers and pasta).
  2. Eat when you're hungry and let fat burn between meals (limit your snacking).
  3. Be active (exercise burns fat).
  4. Avoid eating dinner or snacking after 8:00 pm.
  5. Consider a simple form of intermittent fasting that works for you.

These rules of thumb will help you to find the right balance and customize your eating patterns to your body.

So, is intermittent fasting a healthy choice for everyone

Bottom line, intermittent fasting isn't necessarily healthy or unhealthy. Life is about balance and the same applies to eating. Our individual bodies are all different, requiring different things.

Rather than trying to adhere to the rules of a hard, fast diet, listen to what your body is telling you. Pay attention to how your body feels during and after eating certain foods, and use an approach that is sustainable and works best for your lifestyle.

Let's make healthy a lifestyle - together!

XOXO,
Pam & Kalie

What has your experience been with intermittent fasting? Share below!

Sources:

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  2. Tello, MD, MPH, M. (2020). Intermittent fasting: Surprising update. [online] Harvard Health Publishing Harvard Medical School. Available at: https://www.health.harvard.edu/blog/intermittent-fasting-surprising-update-2018062914156 [Accessed 28 Feb. 2020].
  3. N Harvie, M. (2016). Could Intermittent Energy Restriction and Intermittent Fasting Reduce Rates of Cancer in Obese, Overweight, and Normal-Weight Subjects? A Summary of Evidence. [online] Advances in Nutrition An International Review Journal. Available at: https://academic.oup.com/advances/article/7/4/690/4568691 [Accessed 29 Feb. 2020].
  4. Bendix, A. (2019). 8 signs your intermittent fasting diet has become unsafe or unhealthy. [online] Business Insider. Available at: https://www.businessinsider.com/signs-intermittent-fasting-unsafe-unhealthy-2019-7#intermittent-fasting-can-disrupt-your-sleep-which-is-critical-to-health-2 [Accessed 28 Feb. 2020].
  5. Grayland-Leech, B. (2020). Refined carbs: What they are, and how to avoid them. [online] Medicalnewstoday.com. Available at: https://www.medicalnewstoday.com/articles/refined-carbs#effects [Accessed 28 Feb. 2020].