by Tharien van Eck, AWC Antwerp and Health Team Co-Chair
The aim of this short article is to create more awareness of intermittent fasting, the value of it and how to approach it. It is always important to seek the input of your personal physician when trying to lose weight, especially to ensure that you do not have any underlying medical conditions, or micronutrient deficiencies.
Mark Mattson, a Johns Hopkins neuroscientist, has studied intermittent fasting for many years; he indicated that our bodies can go without food for many hours, even days. In prehistoric times, hunters and gatherers had to go without food for long periods in between hunting and gathering food.
What is intermittent fasting?
It is a program of restricting calorie intake daily for certain periods during the week. One method is that of the 5:2 approach, with fasting on 2 non-consecutive days per week. Another is a time-restricted approach where eating is limited to 8 hours per day, with a fasting period of 16 hours per day.
Mattson calls the period after fasting “metabolic switching” where the body, after having exhausted its sugar stores, starts to burn fat.
Do not confuse fasting for religious and other reasons with intermittent fasting! Longer periods without food (24-72 hours and more) may be unhealthy for you; the body perceives itself to be in a state of starvation, and starts to store fat instead of burning it.
It is also important to acknowledge that it can take your body up to two weeks to become accustomed to intermittent fasting.
Can I eat during intermittent fasting?
No, but you can have black coffee, tea, water or other zero-calorie beverages.
Is intermittent fasting the best approach to maintain healthy weight or to lose weight?
This is still uncertain. A recent study, with about 600 participants (with an average weight loss of 4-8% of their body weight), found that the outcomes were similar over a six-month period to those of individuals following a calorie-restricted diet.
It is important to note that there is no “one size fits all” method when it comes to managing your weight and health. It therefore is important to always discuss weight management plans with your treating physician.
Does intermittent fasting impact your BMI?
The Body Mass Index (BMI) is a comparison of height versus weight. It is widely used but has limitations of which we all should be aware. It is not the perfect indicator of your weight or general health. Intermittent fasting can lead to a reduction in your BMI.
Is there a difference between males and females with reference to intermittent fasting?
Differences seem to be limited at this moment, but more research is required.
Is intermittent fasting a good solution to long-term weight management?
You must always discuss your nutritional plan with your physician if you have any underlying medical conditions. It is important that your diet meets personal preferences, medical conditions and treatment plans.
Successful long-term weight management requires a multi-faceted approach with a good nutritional plan, reassessment of physical activity and other possible lifestyle changes. Intermittent fasting may be good for some individuals, but it is not the answer for all. You may have to consider psychological therapy, pharmacological therapy, or even bariatric surgery to support your weight management.
Who should not consider intermittent fasting?
It is important to acknowledge that intermittent fasting is not suitable for all people. People in the following categories should always consult their physicians before attempting intermittent fasting:
- Children and teens under age 18.
- Women who are pregnant or breastfeeding.
- People with type 1 diabetes; the concern here is an intermittent fasting eating pattern may impact glucose control, and that there could be an increased risk of hypoglycemia during the fasting period.
- Those with a history of eating disorders.
Finally, what are the benefits of intermittent fasting?
More research is still required, but there is consensus that it has several positive outcomes. According to Matson: “Many things happen during intermittent fasting that can protect organs against chronic diseases like type 2 diabetes, heart disease, age-related neurodegenerative disorders and even inflammatory bowel disease and many cancers.” Here are some intermittent fasting benefits research has revealed so far:
- Enhanced thinking and memory
- Improved blood pressure, resting heart rates and other heart-related measurements.
- Animal studies showed that intermittent fasting prevented obesity. There is evidence, from several small studies, that obese adult humans lose weight through intermittent fasting. The postulation therefore is that people with type 2 diabetes may benefit from intermittent fasting and a potential reversal of the need for insulin therapy.
- There also seems to be a reduction in tissue damage in surgery and improved results.
Sources:
- Is intermittent fasting good for me? Your questions answered | Truth About Weight.global
- Intermittent Fasting: What is it, and how does it work? | Johns Hopkins Medicine.
- Intermittent fasting: What are the benefits? | Mayo Clinic
- Intermittent fasting (IF): Your complete guide | Diet Doctor
- How to reverse your type 2 diabetes | Diet Doctor
- Books addressing the topic:
- The Longevity Diet, by Prof Valter Longo
- The Obesity Code, by Dr. Jason Fung
- Fast Like A Girl, by Dr. Mindy Pelz
- Intermittent Fasting Transformation, by Cynthia Thurlow, NP
Photo: Canva