Starting Intermittent Fasting? Here's What You Need To Know

5 min read

Woman hands doing a stop sign while holding a clock in front of a bowl of cereal and fruits.

Intermittent fasting has been gaining popularity as a new trend in the world of health and nutrition.

It has been shown to have numerous health benefits, including weight loss, improved blood sugar control, and decreased inflammation (1).

If you're thinking about starting intermittent fasting, this article will provide a comprehensive overview of what it is, and how it works with tools to help you get started.

How does intermittent fasting work?

It works by alternating periods of eating and fasting. By doing this, you are able to give your body a break from digesting food and allow it to focus on other important processes, such as repair and regeneration.

There are several different types of intermittent fasting, each with its own specific fasting and eating periods. The most common types include:

  • Time-restricted feeding: restricting your eating window to a certain number of hours per day, such as 8 hours of eating and 16 hours of fasting.

  • Alternate day fasting: alternating between days of normal eating and days of very low calorie intake, usually around 500-600 calories per day.

  • 5:2 fasting: eating normally for five days of the week and restricting calorie intake to around 500-600 calories for two non-consecutive days of the week.

  • Periodic fasting: This involves longer periods of fasting, such as 24-48 hours, done intermittently, with normal eating in between fasts.

  • Meal skipping: skipping one or two meals per day, typically breakfast or lunch, and eating within a shorter time frame during the day.

During the fasting periods, you refrain from consuming calories or limit caloric intake to a very low level. This can lead to a calorie deficit, which can result in weight loss and other health benefits.

What are the benefits?

When applied correctly, this lifestyle can provide numerous health benefits. Here are a few:

  • Weight loss: It can help you lose weight by reducing calorie intake and increasing fat burning (2).

  • Improved metabolic health: Intermittent fasting can improve metabolic health by reducing insulin resistance, decreasing inflammation, and improving blood sugar control (3).

  • Increased longevity: Studies have shown that intermittent fasting may increase lifespan and reduce the risk of age-related diseases (4).

  • Improved brain function: It has been shown to improve cognitive function, increase brain-derived neurotrophic factor (BDNF) levels, and reduce the risk of neurological diseases (5).

  • Reduced inflammation: It can decrease inflammation in the body, which is a contributing factor to many chronic diseases (6).

  • Better heart health: It may improve heart health by reducing blood pressure, triglycerides, and cholesterol levels (7).

  • Prevent disease: It can increase autophagy, a process in which the body breaks down and recycles damaged cells, which can help to prevent disease (8).

While it has its benefits, intermittent fasting may not be suitable for everyone. There are some limits to its use that one should take into account when beginning this way of life.

Potential limits

Risks to consider when starting intermittent fasting include:

  • Potential side effects: Some people may experience headaches, dizziness, and fatigue during the fasting period (9).

  • Overeating: Some people may overeat during their eating window, which can negate the benefits of fasting and lead to weight gain (10).

  • Muscle loss: Prolonged fasting or inadequate protein intake can lead to muscle loss, especially in those who are physically active (11).

This way of eating may not be recommended for individuals with certain medical conditions, for pregnant or breastfeeding women, but it is generally safe for healthy individuals. Approaching it with caution and being aware of any potential limitations is important to ensure a smooth transition into this lifestyle.

Tools in your pocket

Adopting a fasting lifestyle can be daunting, but there are several apps available that can be useful for those who want to start and track their progress. Here are a few:

The Tracker

From ketone to glucose levels, this app allows users to track many health indicators to have a better insight of their progress since they started fasting. Users can take on challenges with others participants and have access to informative articles on fasting.

application icon
Zero: Fasting & Health Tracker
Zero Longevity Science, Inc.
apple is available for this applicationandroid is available for this application
In-app purchases

The All-In-One

Providing more than 10 fasting plans, tailored recipes, a fasting timer with reminders, a weight and water tracker, this app is ideal for users who require continuous guidance in their fasting journey.

apple is available for this applicationandroid is available for this application
In-app purchases

The Simple and Efficient

Straight to the point, this app allows users to track their fasting time based on their goals. They can log their weight and have access to educational content.

apple is available for this application
In-app purchases

The Go-To

While tracking their fasting time, users can have an overview of their body status knowing when they are starting to burn fat. They can log their weight, water intake, and steps. There are also recipes and educational articles. To stay motivated, users receive rewards after completing a day of fasting.

application icon
Fastic – Intermittent Fasting
HealthVida GmbH & Co. KG.
apple is available for this applicationandroid is available for this application
In-app purchases

A new way to eat

All in all, there are multiple fasting methods with unique eating windows, all offering numerous health benefits. If you're considering exploring this new lifestyle, utilizing one of the selected apps to track your progress can be helpful.

When it comes to nutrition, there is no universal solution that works for everyone. The only way to find out is to try it out.


  1. Wilhelmi de Toledo F, Grundler F, Sirtori CR, et al: Unravelling the health effects of fasting: a long road from obesity treatment to healthy life span increase and improved cognition. Ann Med 52:147–161, 2020.

  2. Johnstone A: Fasting for weight loss: an effective strategy or latest dieting trend? Int J Obes (Lond) 39:727–733, 2015

  3. Barnosky AR, Hoddy KK, Unterman TG, et al: Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings [Internet]. Translational Research 164:302–311, 2014[cited 2023 Mar 9] Available from:

  4. Sogawa H, Kubo C: Influence of short-term repeated fasting on the longevity of female (NZB×NZW)F1 mice [Internet]. Mechanisms of Ageing and Development 115:61–71, 2000[cited 2023 Mar 9] Available from:

  5. Lee J, Duan W, Long JM, et al: Dietary restriction increases the number of newly generated neural cells, and induces BDNF expression, in the dentate gyrus of rats. J Mol Neurosci 15:99–108, 2000.

  6. Wang X, Yang Q, Liao Q, et al: Effects of intermittent fasting diets on plasma concentrations of inflammatory biomarkers: A systematic review and meta-analysis of randomized controlled trials. Nutrition 79–80:110974, 2020.

  7. Yang F, Liu C, Liu X, et al: Effect of Epidemic Intermittent Fasting on Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Front Nutr 8:669325, 2021.

  8. Antunes F, Erustes AG, Costa AJ, et al: Autophagy and intermittent fasting: the connection for cancer therapy? Clinics (Sao Paulo) 73:e814s, 2018.

  9. Hoddy KK, Kroeger CM, Trepanowski JF, et al: Safety of alternate day fasting and effect on disordered eating behaviors. Nutr J 14:44, 2015.

  10. Rosas Fernández MA, Concha Vilca CM, Batista LO, et al: Intermittent food restriction in female rats induces SREBP high expression in hypothalamus and immediately postfasting hyperphagia. Nutrition 48:122–126, 2018.

  11. Laurens C, Grundler F, Damiot A, et al: Is muscle and protein loss relevant in long-term fasting in healthy men? A prospective trial on physiological adaptations. J Cachexia Sarcopenia Muscle 12:1690–1703, 2021.

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