Benefits of fasting for your health
Despite its recent surge in popularity, fasting is a practice that dates back centuries and plays a central role in many cultures and religions. Defined as the abstinence from all or some foods or drinks for a set period of time, there are many different ways of fasting. In general, most types of fasts are performed over 24–72 hours.
Intermittent fasting, on the other hand, involves cycling between periods of eating and fasting, ranging from a few hours to a few days at a time. Fasting has been shown to have many health benefits, from increased weight loss to better brain function.
Promotes Blood Sugar Control by Reducing Insulin Resistance
Several studies have found that fasting may improve blood sugar control, which could be especially useful for those at risk of diabetes. In fact, one study in 10 people with type 2 diabetes showed that short-term intermittent fasting significantly decreased blood sugar levels . Meanwhile, another review found that both intermittent fasting and alternate-day fasting were as effective as limiting calorie intake at reducing insulin resistance (2).
Decreasing insulin resistance can increase your body’s sensitivity to insulin, allowing it to transport glucose from your bloodstream to your cells more efficiently. Coupled with the potential blood sugar-lowering effects of fasting, this could help keep your blood sugar steady, preventing spikes and crashes in your blood sugar levels. Keep in mind though that some studies have found that fasting may impact blood sugar levels differently for men and women.
May Enhance Heart Health by Improving Blood Pressure, Triglycerides and Cholesterol Levels
Heart disease is considered the leading cause of death around the world, accounting for an estimated 31.5% of deaths globally.
Switching up your diet and lifestyle is one of the most effective ways to reduce your risk of heart disease. Some research has found that incorporating fasting into your routine may be especially beneficial when it comes to heart health. One small study revealed that eight weeks of alternate-day fasting reduced levels of “bad” LDL cholesterol and blood triglycerides by 25% and 32% respectively.
Aids Weight Loss by Limiting Calorie Intake and Boosting Metabolism
Many dieters pick up fasting looking for a quick and easy way to drop a few pounds. Theoretically, abstaining from all or certain foods and beverages should decrease your overall calorie intake, which could lead to increased weight loss over time. Some research has also found that short-term fasting may boost metabolism by increasing levels of the neurotransmitter norepinephrine, which could enhance weight loss (17). In fact, one review showed that whole-day fasting could reduce body weight by up to 9% and significantly decrease body fat over 12–24 weeks (18).
Another review found that intermittent fasting over 3–12 weeks was as effective in inducing weight loss as continuous calorie restriction and decreased body weight and fat mass by up to 8% and 16% respectively . In addition, fasting was found to be more effective than calorie restriction at increasing fat loss while simultaneously preserving muscle tissue .
Could Delay Aging and Extend Longevity
Several animal studies have found promising results on the potential lifespan-extending effects of fasting. In one study, rats that fasted every other day experienced a delayed rate of aging and lived 83% longer than rats that didn’t fast (27). Other animal studies have had similar findings, reporting that fasting could be effective in increasing longevity and survival rates.
However, current research is still limited to animal studies. Further studies are needed to understand how fasting may impact longevity and aging in humans.