INTERMITTENT FASTING FOR WEIGHT LOSS
Changes to our diet are often used as a tool to improve weight and promote weight loss. Managing your weight contributes to good health now and as you age. A healthy body weight is associated with positive health outcomes, better mental health, and improved quality of life (1). There are a variety of ways to change your diet to promote weight loss. Let us dive into a popular eating plan to better understand how to intermittent fast for potential weight loss.
WHAT IS INTERMITTENT FASTING? WHAT ARE THE DIFFERENT TYPES?
Intermittent fasting (IF), also called time-restricted eating, is a type of nutrition plan where you only eat during a specific timeframe. There are different types of IF which include:
- 16/8: Fast for 16 hours and only eat during an eight-hour window within a 24-hour day, this is the most followed IF plan
- 5:2: Fast for two days and feast for 5 days of the week
- Alternating days: Alternating a ‘fast day’ of consuming 0–500 calories with a feasting day. The alternating day of fasting is the most common type of IF clinically studied.
One of the unique things about IF is there are no restrictions on what you can eat, just when you can eat. If you choose to follow IF, choose whichever type you feel fits best with your lifestyle.
DOES INTERMITTENT FASTING WORK?
How intermittent fasting works is the theory of using stored energy within the body instead of constantly relying on food intake. Some scientists call this ‘metabolic switching’, meaning we start using more fat within our bodies as an energy source instead of the calories we just ate from food. Because of our modern lifestyle, we typically eat more throughout the day than we probably need. Intermittent fasting allows us to get back closer to the hunter-gather states of evolution when our bodies adapted to no food intake (or metabolic switching).
When compared with other types of diets to promote weight loss, high protein, low-carbohydrate diets and IF promoted greater weight loss compared to other popular diets (2). When intermittent fasting was compared to a calorie-restricted diet only, similar weight loss occurred (3). A key component of weight loss is a negative calorie balance. Therefore, by restricting the time allowed to eat, IF has been successful at promoting weight loss. It should be noted long-term studies on IF are limited, so we aren’t sure if you will continue to lose weight after initially following an IF eating plan.
HOW TO INTERMITTENT FAST FOR WEIGHT LOSS?
Thinking about starting an intermittent fasting program? Here’s some commonly asked questions:
WHAT TO EAT DURING INTERMITTENT FASTING?
If you’re interested in trying IF for weight loss you might be asking yourself what to eat during intermittent fasting. Intermittent fasting does not prescribe specific types of foods to include or exclude and does not restrict calories during the feeding window. Guidance for IF is ad lib, meaning eat when you are hungry. One potential downfall of IF is there may be key micronutrients missing due to reduced food intake. Therefore, adding a multivitamin can help close the gaps in nutrient intake while fasting.
CAN YOU DRINK COFFEE WHILE INTERMITTENT FASTING?
During the fasting timeframes of the diet, black coffee with no cream or sugar is permitted. Sorry cappuccinos, no room for you during our fasting window! Additives in our coffee like cream and sugar contain calories which would break the fast.
HOW MANY CALORIES TO EAT DURING INTERMITTENT FASTING 16/8?
There is no calorie restriction while following the 16/8 IF plan. Keep in mind, the timeframe while eating is not an excuse to eat highly processed foods with added sugars and fats. Try to focus on choosing nutrient-dense foods most often to support overall health and weight management.
THE TAKE HOME ABOUT INTERMITTENT FASTING
Based on what we know, intermittent fasting can be a tool to promote weight loss. If you think intermittent fasting is the right plan to help achieve your weight loss goals, round out your wellness routine by adding in some daily exercise which could be done on a yoga mat. In studies where participants followed a fasting diet plan in conjunction with exercise, they lost more weight compared to just fasting (4). Intermittent fasting can help reduce your overall calories which helps to promote weight loss. Choose the style that works best for you and add in your favorite type of exercise for additional health benefits!
References
1. Health Effects of Overweight and Obesity. Retrieved from Health Effects of Overweight and Obesity | Healthy Weight, Nutrition, and Physical Activity | CDC
2. Freire, R., 2022. Scientific evidence of diets for weight loss: Different macronutrient composition, intermittent fasting, and popular diets. [online] Available at: <https://www.sciencedirect.com/science/article/abs/pii/S0899900719301030> [Accessed 14 October 2022].
3. Rynders CA, Thomas EA, Zaman A, Pan Z, Catenacci VA, Melanson EL. Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy
Restriction for Weight Loss. Nutrients. 2019; 11(10):2442. https://doi.org/10.3390/nu11102442
4. Welton, S., Minty, R., O’Driscoll, T., Willms, H., Poirier, D., Madden, S. and Kelly, L., 2022. Intermittent fasting and weight loss: Systematic review. [online] The College of Family Physicians of Canada. Available at: <https://www.cfp.ca/content/66/2/117.full> [Accessed 14 October 2022].
