Fast and Curious
There are a variety of fasting practices across the world practiced for health, religion, and cultural reasons. Intermittent fasting (IF) is widespread practice here in America and has been gaining popularity. IF is also known as time-restricted eating (TRE) because you choose the timeframe (window) you will eat and not eat. The most common intermittent fasting schedule is the 16/8 method. 16 hours of fasting and 8 hours to eat. Other methods are the 5:2 plan which is eating for 5 days and fasting for 2 days a week or eating every other day. Another fast is referred to as periodic fasting typically involving only water for 2-7 days. For most, a variety of foods can be eaten, however, nutritional dense foods and avoiding processed foods will have enhanced health benefits. Adding exercise with IF improves the benefit of weight loss. 1 History shows religions and certain cultures abstaining from food to focus on God and self-reflection and yet others had no choice to fast due to short-term food availability. A plethora of research shows us many benefits; however, with all the benefits and media influences begs the question is it right and safe for everyone?
Starving the flesh, healing the body
Intermittent fasting is an avenue to restrict calories so the body will use stored fat which helps lower insulin levels. 1 Lower insulin levels help with weight loss and reduced risk of diabetes and improved metabolic health and autophagy (cell death) to clean up damaged cells. 1 Other than losing weight, IF has the potential to boost immunity, reduce risk of cardiovascular disease, diabetes, and cancer, balancing hormones, increasing metabolic health, and aid in longevity. 2 These benefits come from decreased insulin levels, ketone bodies, reduced oxidative stress, effects on circadian rhythm, and enhancing the gut microbiome. 1 In an umbrella study of twenty-three studies, waist circumference, fat mass, and LDL significantly decreased and for obesity patients IF lowered fasting blood glucose compared to people with no obesity. 3 It is also interesting to note that IF (or TRE) provides a structured eating window for people to follow which may be helpful for those trying to lose weight. The main benefit of IF seemingly is for those who are overweight or obese to improve cardiovascular and metabolic health.
To fast or not to fast
IF is not recommend for certain phases of life or disease. Infants, puberty, adolescents, pregnant and lactating women, older individuals, type 1 diabetic patients, underweight individuals, and those with an eating disorder are not recommended to fast. 1 In addition, those participating in intensive training, people taking medication needed with food, taking certain medications like insulin, and seizures patients should not fast without medical approval or guidance. It was found in an online cross-sectional survey that 46% of the participants who fasted were associated with more symptoms of orthorexia nervosa which is the desire to eat healthy foods and fasting individuals had more eating disorder symptoms. 4 Fasting seems to exacerbate people who have an eating disorder and should not fast.
Challenges
The initial upfront challenge of any type of fast is denying yourself food in a food noise society. Other challenges are dealing with hunger pains and withdraw symptoms of headaches, fatigue, irritability, hunger, weakness, dizziness, nausea, bad breath, excessive urinating, constipation, anxiety, and sleep disruptions. 5 Headache was the most common symptom in a cross-sectional study of 147 Saudia Arabia participants, and the most severe symptoms were lethargy. 5 Fasting can take time upfront to plan and prepare. Choosing a fast you can best adhere to is the obvious choice. Secondly, preparing for a fast mentally and meal planning can set one up for success.
Fasting forward
Intermittent fasting can be a wonderful way to have long-lasting health benefits. For those overweight or obese this could be an easier approach to lose weight verses strict diets to follow. Focusing on whole food and adding in exercise will enhance the benefits of fasting for overall wellness.
References:
1. Soykurt SÇ, Tekdemir SN. Intermittent Fasting and Its Potential Effects on Health. Cyprus Journal of Medical Sciences. 2024;9(4):221-227. doi:10.4274/cjms.2024.2023-109
2. Reddy BL, Reddy VS, Saier MH Jr. Health Benefits of Intermittent Fasting. Microb Physiol. 2024;34(1):142-152. doi:10.1159/000540068
3. Sun M, Yao W, Wang X et al. Intermittent fasting and health outcomes: an umbrella review of systematic reviews and meta-analyses of randomised controlled trials eClinicalMedicine, 2024; 70
4. Domaszewski P, Rogowska AM, Żylak K. Examining Associations Between Fasting Behavior, Orthorexia Nervosa, and Eating Disorders. Nutrients. 2024;16(24):4275. doi:10.3390/nu16244275
5. Shalabi H, Hassan AS 4th, Al-Zahrani FA, et al. Intermittent Fasting: Benefits, Side Effects, Quality of Life, and Knowledge of the Saudi Population. Cureus. 2023;15(2):e34722. Published 2023 Feb 7. doi:10.7759/cureus.34722.
6. Figures are MS stock images