Over the last several decades, numerous diet fads have come and gone in remarkably rapid succession. Atkins, Paleo, Veganism, Ketosis, and so much more have given way to the newest dietary fad: Intermittent Fasting. Will this latest lifestyle adjustment lead to improved health and weight loss, or is it just another fad destined to fade into oblivion along with its predecessors?
The Theory of Intermittent Fasting
The effectiveness of any diet comes down to the depletion of calories. Ketosis diets eliminate the calories obtained from carbohydrates, compared to vegetarian-based diets that remove meat-based calories. The theory behind intermittent fasting lies in limiting the total intake of calories by skipping meals or limiting the amount of time during the day it is possible to intake food. This appears to come with a caveat: Wouldn’t the effects be negated if you consume double or triple the calories during that period? In reality, a Canadian Family Physician study in 2020 found a range of .8% to 13% drop in overall weight for intermittent fasters, regardless of their overall caloric intake. Could these results be indicative of significant health benefits beyond dieting?
How Intermittent Fasting Improves Overall Health
On top of all the fat-burning, several possible benefits may correlate with Intermittent Fasting. One New England Journal of Medicine study found multiple benefits, including stress relief, cognitive improvements, and anti-aging effects. The same study also indicated that Intermittent Fasting might be able to fight diseases like cancer, asthma, arthritis, and neurological disorders. It is not entirely clear why these benefits occur, though. The authors state, “Although we do not fully understand the specific mechanisms, the beneficial effects of intermittent fasting involve metabolic switching and cellular stress resistance.”
The Challenges of Intermittent Fasting
In American culture, three meals and snacks every day are the standard. For many, this can be difficult to transition to a restrictive diet. Some people experience difficulty concentrating and irritability in their first month of transitioning to Intermittent Fasting. Many people will also find it challenging to stick with this program long-term. Benefits vary from person to person, and while this data is impressive, these findings are based on results of tests on rodents, and there is more data required to confirm equal human benefits.
1. Welton S, Minty R, O’Driscoll T, Willms H, Poirier D, Madden S, Kelly L. Intermittent fasting and weight loss: Systematic review. Can Fam Physician. 2020 Feb;66(2):117-125. PMID: 32060194; PMCID: PMC7021351. Citations: 111.
- de Cabo, R., & Mattson, M. P. (2019, December 26). Effects of Intermittent Fasting on Health, Aging, and Disease. New England Journal of Medicine, 381(26), 2541–2551. https://doi.org/10.1056/nejmra1905136. Citations: 779