By Reagan McNeill
With there being different diets that are for different things, there are two main diets that have become popular recently, intermittent fasting and calorie restriction. These two diets have been controversial since there is not much research on which is better than the other for weight loss. In this post we will explore what intermittent fasting is and if it is better than a calorie restricted diet.
What is Intermittent Fasting?
Intermittent fasting is when you eat during a period then you do not eat for a different amount of time that equals up to 24 hours. There are many different variations with 16/8 being the most popular option. This is where you fast by eating very few to no calories for 16 hours then eat a normal amount of calories for 8 hours.
Although 16/8 is a common choice for intermittent fasting there are different fasting choices that people choose. There is a 5:2 fasting option where you fast for 5 days and have no restrictions for 2 days. There are also other options for fasting that are more than or less than 16 hours, although fasting for 24 hours or longer may not be beneficial and not healthy for you.
Does Intermittent Fasting Result in Weight Loss?
Although there is not much research to show the full benefits of intermittent fasting, there is some research to show if it helps with weight loss. The researcher designed a randomized clinical trial with obese adults that had a mean BMI 34 between 18 and 64 over 1 year. The participants were arranged into 3 groups: Alternate-day fasting where they consumed 25% energy needs on fasting days and 125% on feasting days, a calorie restriction diet where they consumed 75%, and no-intervention. The trial involved a 6-month weight loss phase and a 6-month weight-maintenance phase (JAMA Intern Med., 2017).
During the trial they recorded the dropout rate reporting that the intermittent fasting group had the highest dropout rate. 38% of the intermittent fasting group dropped out while 29% of the calorie restricted diet dropped out and 26% of the control dropped out. Although there was a significant amount of people that dropped out, they found out that during both 6-month intervals that intermittent fasting and calorie restriction had the same effect. The mean of both groups around the 6-month mark was -6.8% and around the 12-month mark intermittent fasting mean was -6.0% and calorie restriction mean was -5.8% (JAMA Intern Med., 2017).
Sample Day on Intermittent Fasting?
Here is what a typical day looks like with someone on a 16/8 fasting:
Breakfast:
· Water
Snack:
· Water
Lunch:
· Grilled Chicken
· Roasted vegetables
Snack before workout:
· Protein shake
Dinner:
· Salad
· Spaghetti
Is Intermittent Fasting the Choice for You?
Intermittent fasting can sound very appealing, but it is not for everyone. It is not for anyone who is either under 18, pregnant or breastfeeding, has type 1 diabetes and needs insulin, and has a history of eating disorders. It is also recommended to be aware of the symptoms that may come with it including unusual anxiety, nausea, headaches or other symptoms that may not be usual.
References
Collier, R. (2013, June 11). Intermittent fasting: The science of going without. CMAJ : Canadian Medical Association journal = journal de l’Association medicale canadienne. https://pmc.ncbi.nlm.nih.gov/articles/PMC3680567/
Farash, T., Al Oran, H., Baqleh, R., Hazza’Obaida, H., & Al-Rahamneh, H. (2023, April 4). The effect of intermittent fasting on psychological wellbeing among disabled individuals versus able-bodied peers. Journal for ReAttach Therapy and Developmental Diversities. https://jrtdd.com/index.php/journal/article/view/892
Joseph, R. (2022, July 28). Intermittent fasting: What is it, and how does it work? | Johns Hopkins Medicine. Should you try intermittent fasting for weight loss? https://www.hopkinsmedicine.org/health/wellness-and-prevention/intermittent-fasting-what-is-it-and-how-does-it-work
Mayo Foundation for Medical Education and Research. (2025, March 8). What is intermittent fasting and can it be healthy?. Mayo Clinic. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/intermittent-fasting/faq-20441303
Trepanowski, J. F., Kroeger, C. M., Barnosky, A., Klempel, M. C., Bhutani, S., Hoddy, K. K., Gabel, K., Freels, S., Rigdon, J., Rood, J., Ravussin, E., & Varady, K. A. (2017, July 1). Effect of alternate-day fasting on weight loss, weight maintenance, and cardioprotection among metabolically healthy obese adults: A randomized clinical trial. JAMA internal medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC5680777/
About Author
Reagan McNeill is a current student at East Tennessee State University studying Nutrition.