Fasting to live better?

#Obesity #IntermittentFasting #Nutrition


Obesity is a chronic, multifactorial disease that is steadily increasing worldwide, now affecting more than 650 million adults. It is strongly associated with an increased risk of type 2 diabetes, cardiovascular diseases, certain cancers, and a wide range of metabolic and functional complications. Beyond its impact on physical health, it also leads to a decrease in quality of life, social stigma, and a significant economic burden on healthcare systems.

Traditional weight loss approaches are mainly based on continuous calorie restriction, often combined with increased physical activity. While they can be effective in the short term, long-term adherence is often compromised by fatigue, dietary monotony, feelings of hunger, and the difficulty of maintaining a constant energy deficit. Moreover, results vary considerably from one individual to another, and many patients regain weight after stopping the diet.

In this context, intermittent fasting (IF) has emerged as an alternative nutritional strategy, aiming to modulate periods of eating and fasting rather than strictly reducing daily caloric intake. This eating pattern may promote not only weight loss but also improvements in cardiometabolic markers, while potentially being better accepted by some patients.

This study was designed to assess the effectiveness of various intermittent fasting protocols on body composition and cardiometabolic parameters in overweight or obese adults. The analysis also aimed to compare the effects according to the duration of interventions and the type of protocol used, in order to identify the most beneficial and sustainable approaches.  

And if skipping meals melted more than just weight?

Fifteen randomized controlled trials, including a total of 758 overweight or obese adult participants, were analyzed, with interventions lasting from 6 to 16 weeks. The intermittent fasting protocols assessed varied and included time-restricted eating (TRE), alternate-day fasting (ADF), the 5:2 diet, the 4:3 diet, and intermittent energy restriction (IER).

The results show that intermittent fasting induces a significant reduction in body weight and body mass index, as well as a decrease in total cholesterol and LDL cholesterol. It also leads to a modest but significant reduction in diastolic blood pressure. Conversely, no notable effect was observed on fasting glucose, HbA1c, systolic blood pressure, waist circumference, or waist-to-hip ratio.

A transient increase in triglycerides was observed in short-term interventions (≤12 weeks), while the most pronounced metabolic benefits appeared in programs lasting more than 12 weeks. Among the approaches compared, ADF generally proved more effective than TRE for weight loss and LDL improvement, suggesting that the frequency and intensity of fasting periods may influence the magnitude of cardiometabolic effects.

Intermittent fasting: an ally for weight and heart?

Obesity, a major cardiometabolic risk factor, remains a complex therapeutic challenge to manage in the long term. Intermittent fasting stands out as a promising nutritional option. This research indeed demonstrates that this nutritional strategy can significantly reduce body weight and improve certain lipid and blood pressure parameters. However, recent data also show that its effectiveness depends on the chosen protocol and the duration of the intervention.

Future, longer, and better-standardized studies should confirm these results and explore the potential benefits of combining intermittent fasting with other approaches, such as physical activity and an optimized diet, to enhance its benefits and ensure better long-term adherence.   

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