Intermittent Fasting - The Basics
However, “hip” fasting may sound in the world of diet trends, it is far from a fad (and far from a diet in the traditional sense). Since ancient times, fasting has played a role in medicinal, spiritual, and religious practices. Hippocrates, aka “the father of medicine” often recommended abstinence from certain foods and drinks who exhibited certain illnesses, believing a fast or cleanse would aid the body in healing itself.
Today, intermittent fasting has also become a popular choice of practice in wellness circles due to its flexibility. There are several different ways to fast intermittently, including alternate-day fasting, time-restricted feeding, 5:2 fasting, and a fasting-mimicking diet. Read on for more information on what might best fit your needs.
Functional medicine approach to fasting
There are many health benefits to fasting from helping with autoimmune disorders and insulin sensitivity to weight loss and increased brain function. Fasting has been found to reset the immune system, which can be beneficial for autoimmune disorders. The stress fasting causes to your body is considered a “good” or beneficial stress and can help reset your body’s energy, sleep, digestion, and elimination patterns.
Mitochondrial health is also benefited by intermittent fasting. One of the main roles of our mitochondria is to generate energy. In fact, our mitochondria produce approximately 90% of the energy that our body needs and is, therefore, essential to many of our body systems, including cardiovascular, musculoskeletal, gut, brain, and immune systems. Recent studies have shown that keeping your mitochondria healthy is the key to good health and can slow down aging, and prevent metabolic disease, autoimmune disorders, and even cancer.
Your functional medicine practitioner may recommend fasting for the following reasons:
- Obesity
- Insulin sensitivity
- Metabolic syndrome
- Multiple sclerosis (MS)
- Inflammatory Bowel Disease (IBD) or Irritable Bowel Syndrome (IBS)
What is Intermittent fasting?
Intermittent fasting isn’t a diet. It is designed to reset current eating patterns and observe how your body feels. The emphasis is on when you eat, more so than what you eat, though keep in mind that we do recommend you eat a varied diet consisting of grass-fed and pastured meats, and a variety of vegetables, fruits, and good fats.
Intermittent fasting is a pattern of eating where you alternate between eating and fasting on a regular schedule.
It is based on the idea that your body is in a “fed” state while eating, digesting, and absorbing nutrients from your food. This process takes approximately takes three to five hours from the time you begin eating. While you are in a “fed” state, your body increases insulin levels, making it hard for you to burn fat.
The other state is a post-absorptive state when your body has finished absorbing the food you ate. The post-absorptive state lasts approximately eight to 12 hours after your last meal. During this state, your insulin levels decrease, and your body can now burn fat.
Health benefits of intermittent fasting
Intermittent fasting isn’t a diet, and it is designed to take some time to step back from eating patterns and observe how your body feels and change the way you eat rather than what you eat.
Here are just some of the many benefits that intermittent fasting can help with:
- Boosts fat-burning
- Supports weight loss
- Reduces inflammation
- Fights free radical damage
- Reduces cardiovascular risk
- Decreases triglycerides levels
- Helps with insulin sensitivity
- Improves brain function
- Improves blood pressure levels
- Boosts thinking and memory
- Supports normal ghrelin (“hunger hormone”) levels
- Slows the aging process by increasing the rate of HGH production
Gut health with fasting
As mentioned before, intermittent fasting can be good for your gastrointestinal system. According to studies, fasting (especially at night) can improve the gut microbiome and help to heal your gut. Eating a diet rich in probiotics and fermented foods can also help during fasting to improve gut health.
Fasting can also help the gut by:
- Resetting the gut
- Reduce gut inflammation
- Eliminating food sensitivities
Types of intermittent fasting
There are different types of intermittent fasting; the central concept is to pick a block of time when you can eat and a block when you cannot. These are meant to be done consistently as a lifestyle routine.
Alternate day fasting:
This type of fasting is where you fast for one day and eat the next day. Naturally, this type of fasting is not for everyone, and you should check with your functional medicine practitioner or doctor to see if it’s right for you before starting this type of fasting.
Time-restricted feeding:
With this type of fasting, you consume healthy food and beverages during a shortened time of the day regularly. It coincides with your sleep cycle and is often referred to as “prolonged nightly fasting” which makes it easier to achieve. The goal here is to extend your nightly fast to 12 hours or more.
One of the more popular time-restricted feedings is the 16:8 plan. 16:8 intermittent fasting allocates 16 hours to keep a fast and the rest of the day (8 hours) for eating. This enables your body to lower insulin levels and begin to burn fat instead of carbohydrates as it would normally do during the eating period. Other popular time-restricted eating includes the 18:6 and 20:4 fasting.
5:2 fasting:
The 5:2 fasting plan involves five days of unrestricted eating and two non-consecutive days where your caloric intake is low; typically, 500 calories for women and 600-700 calories for men per day. Then the other five days, you eat as you normally would, although it is recommended that you eat a balanced and nutrient-dense diet. Choosing the time of “fed” state and post-absorptive state is also important.
Fast-mimicking diet (FMD)
This is a low-calorie, plant-based diet program high in unsaturated fats while low in sugar and protein. One of the more well-known types of a fasting-mimicking diet is Prolon. This plan has been clinically tested and based on over 20 years of scientific research. It is a 5-day dietary program that enables your body to shift into a fasting state while eating.
Before you begin
As always, there is never one recommendation that suits everyone. We always recommend that you check with your healthcare practitioner before beginning a fasting program of any type. Intermittent fasting should be avoided for children and teens, pregnant or breastfeeding women, people with type 1 diabetes, blood sugar issues, or eating disorders.