With intermittent fasting being so popular, many people are wondering how long to do intermittent fasting before seeing results. Unfortunately, there is no strict timeline for when individuals will see intermittent fasting results. This is because there are factors that are going to going to influence how quickly this happens such as:

  • The physiological and health status of the individual before they start fasting
  • Age
  • Sex
  • Physical activity
  • Type of fasting schedule
  • Sleep schedule

To elaborate, heavier people with more weight to lose may experience weight loss before someone who is trimmer with less weight to lose. Likewise, individuals who are more physically active are likely to lose more weight than people who live a sedentary lifestyle. 

Additionally, individuals who adopt more strict fasting schedules are likely to see results quickly. For example, individuals adhering to a one-meal-a-day (OMAD) fasting schedule are likely to see results quicker than someone who is doing the 16/8 diet. This doesn’t mean that there are no 16/8 fasting results, it just means it may take longer for you to notice them.

Regardless of these influential factors, you will likely see intermittent fasting results after 1 month. Studies have shown significant results with regard to weight loss and some blood markers even in athletes on the 16/8 diet after one month, meaning the average person will likely see them as well since the average person usually has more weight to lose (1). 

Also, read – Get One of The 12 Best Intermittent Fasting App of Today!

Some individuals want to fast for just one day and are curious if they will see any benefits. While you are likely to not lose a significant amount of weight, you can still see some 24-hour fasting results such as beneficial shifts in some blood markers (2). However, more studies are needed to understand the benefits of a short-term fast like this. 

In summary, there is no definitive timeline for when you will see intermittent fasting results. Just know that you will see results so long as you maintain this dietary pattern and that this should be seen as a lifestyle habit, not a short-term fix. 


1. Moro T, Tinsley G, Bianco A, Marcolin G, Pacelli QF, Battaglia G, Palma A, Gentil P, Neri M, Paoli A. Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med [Internet]. BioMed Central; 2016 [cited 2018 Mar 6];14:290. Available from: http://translational-medicine.biomedcentral.com/articles/10.1186/s12967-016-1044-0

2. Palou A, Remesar X, Arola L, Herrera E, Alemany M. Metabolic effects of short-term food deprivation in the rat. Horm Metab Res [Internet]. Horm Metab Res; 1981 [cited 2022 Jun 25];13:326–30. Available from: https://pubmed.ncbi.nlm.nih.gov/7262833/

Asked by: Peter G.

Clinical Project Manager and Writer

With a Ph.D. in nutritional biology, Dr. Richardson is an expert in the field of nutrition, particularly intermittent fasting. Her dissertation project was an intermittent fasting study in athletes, which is where she gained substantial knowledge on the topic. She has contributed to a number of peer-reviewed articles spanning a wide array of topics and works as a freelance writer trying to make scientific knowledge accessible to the public.