Can Intermittent Fasting Improve Insulin Sensitivity?

Intermittent Fasting for Insulin Resistance
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When we think of diets, we most often think of drastic changes to both the type and quantity of food we eat. However, in recent years, nutritionists have begun to focus more attention on the frequency of your meals and how it impacts your overall health. One meal per day, multiple smaller meals, the standard three meals per day -- the list is almost endless for ways in which we can tinker with our eating pattern. While there is still debate regarding the effectiveness of these dietary changes when it comes to weight loss, there is a growing body of evidence that one particular eating pattern significantly improves blood sugar and insulin sensitivity -- intermittent fasting.

Intermittent fasting can take on many forms, but in its simplest sense, it involves spacing meals out further than we are typically used to in modern society. For example, one regimen known as the "16/8 method" involves restricting your daily eating to just 8 hours while fasting for the remaining 16 hours of the day. Another pattern is known as "eat-stop-eat," which involves fasting for 24 hours once or twice per week while eating normally the remainder of the week. While no one intermittent fasting protocol has been shown to be best, the general practice has been recognized by agencies such as the American Heart Association for its ability to reduce insulin resistance and lower the risk of high blood sugar.

Monitoring Blood Sugar with Glucometer
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In 2021, a meta-analysis of 8 different studies focused on how intermittent fasting impacted 3 key measurements of insulin sensitivity: fasting glucose levels, A1C levels, and adiponectin levels. The researchers determined that there was a statistically significant reduction in all 3 statistics when following an eating pattern that involved intermittent fasting. Perhaps more interesting, even in cases in which there was no evidence of weight loss, all study participants still experienced an improvement in insulin sensitivity.

Despite the promising findings, intermittent fasting is not a panacea. There are still some risks associated with this eating pattern, mostly attributed to the addictive qualities of human nature. For example, heavy calorie restriction for a significant part of the day can lead to a loss of self-control when meals are resumed. Moreover, binging episodes can drastically increase blood sugar levels and negate any health benefits.

For this reason, it is important to eat foods low on the glycemic index immediately after a long period of fasting rather than foods that can spike blood sugar levels. Drinking plenty of water in the first few hours following your fast can also help to limit cravings and prevent binges. In addition, make sure to maintain a dialogue with your doctor about any changes you make to your diet.

Jennifer

Jennifer

Jennifer recently retired from her career as a Certified Manual Physical Therapist to spend more time with her family. When she isn't writing about natural medicine, she enjoys practicing yoga, rock climbing, and running marathons.

Email Jennifer at [email protected].

References

  1. Cho Y, Hong N, Kim KW, Cho SJ, Lee M, Lee YH, Lee YH, Kang ES, Cha BS, Lee BW. The Effectiveness of Intermittent Fasting to Reduce Body Mass Index and Glucose Metabolism: A Systematic Review and Meta-Analysis. J Clin Med. 2019 Oct 9;8(10):1645. doi: 10.3390/jcm8101645. PMID: 31601019; PMCID: PMC6832593.
  2. Albosta M, Bakke J. Intermittent fasting: is there a role in the treatment of diabetes? A review of the literature and guide for primary care physicians. Clin Diabetes Endocrinol. 2021 Feb 3;7(1):3. doi: 10.1186/s40842-020-00116-1. PMID: 33531076; PMCID: PMC7856758.
  3. Yuan X, Wang J, Yang S, Gao M, Cao L, Li X, Hong D, Tian S, Sun C. Effect of Intermittent Fasting Diet on Glucose and Lipid Metabolism and Insulin Resistance in Patients with Impaired Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis. Int J Endocrinol. 2022 Mar 24;2022:6999907. doi: 10.1155/2022/6999907. PMID: 35371260; PMCID: PMC8970877.