Intermittent fasting has gained significant popularity, with approximately one in ten Americans engaging in this eating pattern in 2023. As interest in this dietary approach continues to grow, so do the myths surrounding its effects on health. Let’s examine some of the most prevalent misconceptions about intermittent fasting and what current research has to say.
Myth 1: Intermittent fasting negatively impacts sex hormones
Many people worry that intermittent fasting might disrupt hormonal balance, particularly affecting estrogen in women and testosterone in men. However, recent studies paint a different picture:
A 2024 study involving 90 adults with obesity found no significant negative effects on sex hormones.
For women with polycystic ovary syndrome (PCOS), intermittent fasting may actually help regulate hormone levels by decreasing testosterone and increasing sex hormone-binding globulin (SHBG).
It’s important to note that while these findings are promising, more extensive research is needed to fully understand the long-term effects of intermittent fasting on hormonal health.
Myth 2: Intermittent fasting causes greater muscle loss than other diets
Contrary to popular belief, intermittent fasting does not appear to cause more muscle loss than other calorie-restricted diets. A 2022 meta-analysis of randomized trials showed that:
About 75% of weight loss came from fat tissue, while 25% was from lean mass, regardless of the diet strategy.
Combining intermittent fasting with resistance training and adequate protein intake can help preserve lean muscle mass.
Myth 3: Intermittent fasting leads to poor diet quality
Some people believe that fasting periods might lead to overindulgence or poor food choices during eating windows. However, research suggests otherwise:
A 2024 review of randomized control trials found no significant changes in the intake of key nutrients, including fibre, protein, cholesterol, carbohydrates, and various fats, when comparing shorter (4-6 hours) and longer (8-10 hours) eating windows.
It’s worth noting that intermittent fasting alone doesn’t guarantee a nutritious diet. Quality of food choices remains crucial for overall health.
While concerns about the potential link between intermittent fasting and eating disorders are valid, current research doesn’t support this claim:
A 2023 systematic review and a 2019 doctoral thesis following 86 people for four weeks found no evidence that intermittent fasting caused eating disorders in healthy adults.
Some studies suggest intermittent fasting may reduce food cravings and binge-eating behaviours.
It’s crucial to approach these findings with caution. The studies were relatively short-term and screened out individuals with a history of eating disorders. More long-term research is needed to understand the potential risks fully.
Myth 5: Intermittent fasting can cure type 2 diabetes
While some studies suggest that intermittent fasting may help manage type 2 diabetes, calling it a “cure” is premature:
A 2023 randomized control trial showed promising results for diabetes remission through intermittent fasting.
The study was only three months long, and more research is needed to determine long-term effects and sustainability.
Intermittent fasting may help improve insulin sensitivity and blood sugar control, but it’s not a standalone solution for diabetes management. A balanced diet, regular physical activity, and proper medical supervision remain essential.
Myth 6: Intermittent fasting guarantees long-term weight loss
While intermittent fasting can be an effective weight loss strategy for some people, it’s not a magic bullet:
A small randomized control trial found that time-restricted eating produced more weight loss than a control group but was not more effective than calorie restriction.
Long-term weight loss depends on various factors, including overall diet quality, physical activity, and adherence to the eating pattern.
Myth 7: Intermittent fasting is safe for everyone
Although intermittent fasting can be safe for many people, it’s not suitable for everyone:
Pregnant or breastfeeding women
Individuals under 18
People with a history of eating disorders
Those taking medications that require regular food intake
Individuals with certain medical conditions, such as kidney disease or type 1 diabetes
Always consult a healthcare professional before starting any new diet regimen, especially if you have underlying health conditions.
While intermittent fasting shows promise as a dietary approach, it’s essential to separate fact from fiction. As research in this area continues to evolve, maintaining a balanced perspective and seeking guidance from healthcare professionals remains crucial for anyone considering intermittent fasting as part of their health journey.
Cienfuegos, S., Corapi, S., Gabel, K., et al. (2022). Effect of intermittent fasting on reproductive hormone levels in females and males: A review of human trials. Nutrients, 14(11), 2343. https://doi.org/10.3390/nu14112343
Xiao, Y., Zhang, Y., Bian, Y., et al. (2023). Effect of an Intermittent Calorie-restricted Diet on Type 2 Diabetes Remission: A Randomized Controlled Trial. The Journal of Clinical Endocrinology & Metabolism, 108(3), 677-688. https://doi.org/10.1210/clinem/dgac661
Lin, S., Woodward, A., Hu, S., et al. (2023). Time-Restricted Eating Without Calorie Counting for Weight Loss in a Racially Diverse Population: A Randomized Controlled Trial. Ann Intern Med, 176(4), 447-456. https://doi.org/10.7326/M23-0052
Cienfuegos, S., Gabel, K., Kalam, F., et al. (2020). Effects of 4- and 6-h Time-Restricted Feeding on Weight and Cardiometabolic Health: A Randomized Controlled Trial in Adults with Obesity. Cell Metabolism, 32(3), 366-378.e3. https://doi.org/10.1016/j.cmet.2020.06.018
Gabel, K., Hoddy, K.K., Haggerty, N., et al. (2018). Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors in obese adults: A pilot study. Nutrition and Healthy Aging, 4(4), 345-353. https://doi.org/10.3233/NHA-170036
Pellegrini, M., Cioffi, I., Evangelista, A., et al. (2020). Effects of time-restricted feeding on body weight and metabolism. A systematic review and meta-analysis. Reviews in Endocrine and Metabolic Disorders, 21, 17-33. https://doi.org/10.1007/s11154-019-09524-w
Stockman, M.C., Thomas, D., Burke, J., et al. (2018). Intermittent Fasting: Is the Wait Worth the Weight? Current Obesity Reports, 7, 172-185. https://doi.org/10.1007/s13679-018-0308-9
Deixe comentários sobre isso