Can You Use Intermittent Fasting To Get Rid of Stubborn Belly Fat?
By Kayley George, RDN, LD
Do you spend countless hours diving deep into internet holes trying to find trustworthy sources to tell you what you should and shouldn’t be eating? I get it - the internet is FULL of conflicting media messages that promise too-good-to-be-true weight loss messages that can be achieved only weeks before your wedding.
Frustrating, right? Intermittent Fasting (IF) has gained quite a bit of media attention over the past several years as a promising way to lose weight. I have had so many women ask about this topic and the science behind it.
So, here’s my go-to guide on what’s happening on a metabolic level during intermittent fasting. Read on to find out if you should or shouldn’t use intermittent fasting to get rid of stubborn belly fat on your weight loss journey.
What is Intermittent Fasting (IF)?
First off, let’s get a general idea of what exactly IF is. Intermittent fasting is an umbrella term describing a time-restricted eating plan that allows you to eat during certain windows of the day or week.
Usually, there are no guidelines on WHAT to eat, it’s more about WHEN to eat.
When Does The Body Start Burning Fat During Fasting?
As a general rule, your body will begin to burn fat about 10-16 hours after your last meal.
However, there are many variables – it depends on each individual body and type of fasting. For instance, a study with participants that were on an alternate day fasting cycle over 70 days documented a 6% loss in body weight, with a reduction of body fat mass of over 11%. A similar study that decreased food intake to 20% every other day saw a decrease in 8% of body weight in an 8 week period.
Bottom line – fat cells begin to release their stored energy when there is no readily available sugar to be used as energy. And, the longer this period is, the more fat we burn.
Different Ways To Do Intermittent Fasting
There are many different types of intermittent fasting, but here are some of the most common:
5:2 Method
The 5:2 method is when you eat normally for 5 days of the week then engage in a modified fast during the other two. During two non-consecutive days of the week, one might consume only 500 to 600 calories per day.
16:8 Method
The 16:8 method looks at each individual day rather than the week as a whole. During each day, the consumer has an 8 hour window to eat all of his or her calories, leaving 16 hours to fast.
Usually this includes skipping breakfast, then eating in the window of 11am-7pm or 10am-6pm.
Eat-Stop-Eat
This method includes fasting for 24 hours at least once or twice a week with normal eating habits the other days of the week.
Alternate Day Fasting
Eat normally one day, then fast the next. Alternate this.
Usually with fasting days, dieters follow the modified approach, meaning that they can consume around 500 calories.
Using IF To Lose Visceral Fat
A lot of the marketing behind intermittent fasting comes from the claim that IF encourages fat burning in the body and enhances insulin sensitivity. People SWEAR on this, but is this true?
There are several research articles noting the positive impacts of intermittent fasting on metabolic syndrome through its ability to promote lipolysis and insulin sensitivity. Sounds like gibberish to you?
Let's talk about this in more general terms. When we consume food, we’re largely consuming three macronutrients: carbohydrates, fat, and protein. Our body’s preference is to use carbohydrates in its simplest form: glucose.
In times of regular influx of food (no fasting), our body has continuous access to these glucose molecules that come from food every few hours when we eat. When we fast, our body searches for its favorite food (glucose) but can’t find it because we’re not consuming anything. So, our body turns to our glycogen stores (how we store carbs), but this too eventually becomes depleted.
What can our body use for food instead of glucose? It turns to another macronutrient: fat. To use fat as energy, our body has to mobilize it or break it down from its stored form in the body. This is called lipolysis (lipo = fat; lysis = breakdown).
The proposed mechanism of intermittent fasting hones in on the thought that by forcing our body to use our fat stores, we are chipping away at the fat in our body. Sounds ideal, right? Not so quick!
As stated earlier, our body’s favorite food is glucose, or broken down carbohydrate. When we engage in the fasting (lipolysis-enhancing) lifestyle, there are several metabolic changes that are occurring that we should be wary of.
Just as our body can turn to fat as an alternate source of “food,” it can also turn to muscle and protein stores if we delve into fat stores too extensively. Losing muscle in the body is problematic - we need it to maintain a strong metabolism. The more lean muscle mass you have, the more calories you burn naturally.
IF also affects how insulin behaves in our body. When we consume carbohydrates, our body secretes insulin from the beta cells of our pancreas. This insulin is used to drive the glucose in our blood into cells, ultimately decreasing blood glucose.
Does Intermittent Fasting Remove Belly Fat?
The Western Diet today promotes the intake of foods that cause excess and constant secretion of this insulin. Prolonged secretion can lead to insulin resistance, meaning that our blood sugar isn’t getting into the cells and we are stuck with high levels of glucose in the blood.
This can be problematic as it can promote the development of health-related issues such as metabolic syndrome. It also tends to accumulate fat in the abdominal waist area more than any other part of the body. There’s more to that stubborn belly fat!
When we fast, we keep our insulin levels quite low because we’re taking a break from the constant consumption of carbohydrates. Low insulin levels stimulate lipolysis, or the breakdown of fatty acids into the bloodstream for energy use.
Another realm of research looks to explore if fasting in the morning or skipping breakfast leads to overeating in the long run. Surprisingly, much of the research contradicted the old-school theory that skipping breakfast leads to overall increased intake.
In fact, a systematic review exploring the importance of breakfast in the daily routine noted that skipping breakfast is not necessarily correlated with negative weight regulation or overcompensation of calories later in the day. The article highlighted the lack of research and uncertainty and lack of clarity regarding the topic.
One key message to think about is the fact that everyone’s fasting period might look different. Not all intermittent fasting yields the same results for each individual or will get rid of stubborn belly fat.
What Is The Best Intermittent Fasting Window To Lose Belly Fat?
When we lose weight, it is not possible to target a specific area . . . unfortunately. Fat comes off where it comes off!
And, belly fat (the abdominal fat that surrounds our organs) tends to be very resistant to weight loss. IF has been reported to have varying effects on weight loss.
But, all is not lost! A systematic review that compared IF with other restrictive diets found that all had a similar reduction in waist circumference – regardless if it was 16:8, 5:2, Alternate Day, or Eat-Stop-Eat.
However, another study utilizing the 16:8 window showed that while meal timing with longer overnight fasts did not exhibit significant weight loss, there was significantly improved metabolism, lower blood pressure, and reduced appetite.
The available literature does seem to indicate that IF has been shown to have benefits beyond weight loss.
Is IF Sustainable?
The research and science behind IF makes it look pretty attractive, right? So why isn’t IF an option that’s regularly promoted by health professionals as a way to lose weight, especially for lovely ladies like you trying to find the perfect wedding diet to lose some extra pounds before walking down the aisle!?
From the research, it’s evident that there is a lack of studies exploring the long-term effects of IF. Furthermore, the research isn’t exactly standardized.
A lot of the research doesn’t make distinctions between the types of IF that’s being explored which is important since the different types of IF can potentially yield different impacts on how our body reacts.
To be specific, think about all the types of IF I noted above. The 5:2 method, the 16:8 method, alternate day fasting, and eat-stop-eat, these are all different methods that include different time periods of how and when we fast.
Our bodies are miraculous machines. They adapt, address, and react to external changes (like the food we consume). Therefore, it’s important to realize that our body might react differently to the 5:2 method than the 16:8 method.
So If you’re starting fresh with behavior or lifestyle changes, pursuing IF as a first line of action probably isn’t the best idea. It’s important to lay the groundwork for a holistic approach to changing how you eat and before you turn towards approaches that require you to change your eating pattern on such a large level.
There are so many other ways to increase insulin sensitivity and promote visceral fat loss like exercising and improving your carbohydrate choices. Furthermore, there’s many other facets in life that may be negatively affecting your weight, mood, or energy.
It’s also important for me to remind you that food is not the only key that opens the door to weight loss. Don’t forget your exercise, sleep, stress, mindset, and other facets of a well-rounded healthy lifestyle.
The other contraindication for intermittent fasting is anyone with a current or previous eating disorder. Restricting food in this way can be triggering and harmful for anyone who struggles with their relationship to food.
Who is A Good Candidate For Intermittent Fasting?
On the other hand, IF might be an appropriate option to try if you've been pursuing weight loss with proper food choices and exercise regimens for a while (i.e. months) without seeing change.
If you have a known history of blood sugar imbalance, pre-diabetes or diabetes, or PCOS, intermittent fasting can be a great next step to tackle insulin resistance, weight loss, and getting rid of stubborn belly fat.
IF is a flexible tool that you can test out to see if it works for your lifestyle and goals. Give it a few days or weeks to evaluate if it’s a good fit. There can be an adjustment period. It’s a journey to listen to your body and learn what it needs to thrive.
If you are looking to lose visceral fat, you could consider giving intermittent fasting a try. If you do, make sure you use it correctly and in a healthy way to get rid of your stubborn belly fat.
It all comes down to what works for you, not for everyone else. The Healthy Weight Loss team works with you 1:1 to determine what’s the best strategy for your body, lifestyle, and overall calls.
If you’re ready to dive deeper on your weight loss journey, schedule an assessment call with the team today!
Published on Feb 22, 2021 at 8:00 am