Diabetes may occur if the body fails to create insulin (type 1 diabetes) or becomes insulin resistant (type 2 diabetes) (2). Intermittent fasting is an effective strategy to reverse insulin resistance in people with type 2 diabetes. A small study of three people with type 2 diabetes had the people fast for 24 hours, three times a week. After the end of about seven months, all of them had reduced blood sugar, weight, and waist circumference (3). The Journal of Applied Physiology published a study to monitor the effect of intermittent fasting on people with type 2 diabetes. The scientists concluded that intermittent fasting increased insulin actionsevenfold and reduced blood glucose levels in the test subjects (4). Furthermore, a study on diabetic rats showed that intermittent fasting improved glucose homeostasis (maintaining blood glucose levels) (5). Another study concludes that intermittent fasting may be safe and tolerable in people with type 2 diabetes (6). Talk to your doctor before trying intermittent fasting if you have diabetes.
2. Intermittent Fasting May Improve Heart Health
Heart disease is the leading cause of death (7). Poor diet and lifestyle choices are major causes of poor heart health. Intermittent fasting can helplower the risk of cardiovascular diseases. It does this by lowering LDL cholesterol, reducing abdominal fat, decreasing leptin (the hunger hormone) concentration, and improving blood lipid profile (8), (9). A study published in the American Journal of Cardiology shows that people who fast intermittently have a reduced risk of coronary artery disease (10). Intermittent fasting also can help improve cardiac function and potentially reverse cardiomyopathy in mice studies (11). Another study showed that intermittent fasting improved the survival rate of rats with chronic heart failure (12). More human studies need to be done to confirm such findings hold true in humans.
3. Intermittent Fasting Reduces Oxidative Stress
Oxidative stress is the build-up of harmful free oxygen radicals in the body. It occurs due to increased metabolic by-products in the body, dead cells, pollutants, and radiation (13). Antioxidant enzymes, like superoxide dismutase, catalase, and glutathione, help reduce oxidative stress. Researchers have found that intermittent fasting can increase antioxidant enzyme levels in people with obesity (14). Studies show that intermittent fasting increases the level of glutathione and genes that reduce oxidative stress in lab animals (15), (16). Alternate day fasting in overweight adults showed a decrease in oxidative stress levels (17). Decreased oxidative stress, in turn, can help improve heart health and the risk of the following diseases.
4. Intermittent Fasting May Lower Cancer Risk
Cancer is the second leading cause of death. Chemotherapy, surgery, and novel strategies can help manage cancer. New findings show that intermittent fasting without reducing calorie intake is a potential strategy to treat and prevent cancer (18). Fasting alters the growth factor, which affects the cancer cells’ ability to grow and thrive (19). Women who fasted in the night showed reduced breast cancer risk in one study (20). Another study concluded that intermittent fasting could help people tolerate chemotherapy better (21). Intermittent fasting also promotes autophagy (clearing dead cells), which can help reduce tumor cells and increase the effectiveness of radio and chemotherapy (22). A comparative study on mice on a calorie-restricted diet and intermittent fasting stated that the intermittent fasting showed anti-cancer effects (23). However, more research is needed to determine the safety of intermittent fasting on people with cancer and/or undergoing chemotherapy (24).
5. Intermittent Fasting May Help Reduce Blood Pressure
High blood pressure or hypertension is a common genetic and/or lifestyle-related non-communicable disease. Intermittent fasting helps lower blood pressure (25), (26). Women aged 46-62 years showed a decrease in systolic and diastolic blood pressure (27). Time-restricted intermittent fasting also helped lower blood pressure in men with pre-diabetes (28).
6. Intermittent Fasting May Help Prevent Alzheimer’s
Alzheimer’s is a neurodegenerative disease that causes memory loss. Intermittent fasting is emerging as an effective nutritional approach to promote the brain’s ability to restructure its function and prevent memory loss (29). Along with medication and workout, intermittent fasting can be used as a preventive strategy for Alzheimer’s disease (30). A 4-week rat study showed that intermittent fasting may help prevent memory loss (31). Another study on mice concludes that intermittent fasting restores cell membrane protein polarity, which is beneficial for reducing the risk of Alzheimer’s (32).
7. Intermittent Fasting Can Reduce Inflammation
Inflammation is the first step to healing. But chronic inflammation can lead to obesity, diabetes, cancer, arthritis, heart disease, stroke, etc. (33). Intermittent fasting increases adiponectin, a hormone that reduces inflammation (34). Scientists also found that during Ramadan, people practicing intermittent fasting had fewer pro-inflammatory molecules that helped control body weight (35). Intermittent fasting also helped retain muscle mass and reduced inflammation in resistance-trained males (36). Researchers studied the effects of intermittent fasting on mice. They found that intermittent fasting had an anti-inflammatory effect on the neuroimmune system (37). This dietary strategy also reduced inflammatory markers in mice liver and preserved brain and cognitive functions (38), (39).
8. Intermittent Fasting Promotes Autophagy
Autophagy is the removal of damaged cells, proteins, organelles. It occurs in response to toxin build-up and DNA damage. The inhibition of autophagy leads to DNA instability, inflammation, and diseases (40). Intermittent fasting has shown to improve autophagy, which prevents tumor cell growth and increases chemotherapy tolerance (22). Autophagy is beneficial for various types of cancers, like breast cancer, leukemia, ovarian cancer, prostate cancer, myeloma, etc. (41). Short-term fasting also enhances therapeutic neuronal autophagy (42). A study on mice shows that intermittent fasting-induced autophagy decreases fat, prevents obesity, lowers lipid levels, and enhances muscle mass (43).
9. Intermittent Fasting May Help Reduce Belly Fat
Intermittent fasting is a popular method to help people lose weight (44). It can lower LDL cholesterol and BMI in some people and has also been found to help reduce belly fat (45). Scientists have found that intermittent fasting results in lower waist circumference as compared to regimens of people on a calorie-restricted diet (46). Combining intermittent fasting with the Mediterranean diet also resulted in lower abdominal fat in East Asian Americans in a study (47). Another study on people with obesity confirms that intermittent fasting can help reduce waist circumference, fat, and free fat mass (48).
10. Intermittent Fasting May Improve Sleep Quality
Not being able to sleep at night or staying asleep (insomnia) is a sleep disorder. It can increasethe risk of various diseases and impact mental health (49). Fasting intermittently has shown to improve the quality of sleep in people with obesity (50). A study concludes that Ramadan fasting increases daytime sleep (51). Researchers have found that fasting increases alertness but also helps increase sleep time (52). However, more controlled human studies with larger samples are required.
11. Intermittent Fasting Can Help Maintain Muscle Mass
Every year, after the age of 30, muscle loss increases to about 1% of muscle mass per year (53). The mitochondria in the muscles help maintain metabolic health (54). Muscle loss, in turn, slows down metabolism and can lead to age-related obesity (55). Fasting intermittently can help preserve lean muscle (56). However, it is recommended to include resistance training in the workout regimen to lose fat and retain lean muscle while doing intermittent fasting (57).
12. Intermittent Fasting May Increase Longevity
Intermittent fasting can promote healthy aging (58). This, in turn, can increase longevity. It is a scientific functional aging nutritional strategy that induces autophagy (removal of cellular waste), may improve heart health, reduce inflammation, regulate blood pressure, help reduce the risk of various types of cancer, prevent Alzheimer’s and dementia, and is good for people with type 2 diabetes (3), (8), (9), (18), (22), (25), (59), (60). In turn, such health benefits can increase the chances of one living a long, healthy life.
Conclusion
Intermittent fasting is not a fad method for weight loss. It is scientifically proven to aid weight loss and improve health. However, it may not be a safe health solution for everyone, so be sure to talk to your doctor to know if you should fast intermittently and if so, how often in a week you should do it. Can I drink coffee while intermittent fasting? You may have black coffee in moderation, without any added ingredients. Can intermittent fasting help lose weight without exercise? You can lose weight on intermittent fasting even if you don’t exercise. However, if you add exercise, it ensures you lose more fat weight rather than muscle mass. Is it OK to skip breakfast in intermittent fasting? Ideally, with the 16-hour intermittent fasting, you are encouraged to skip breakfast. However, it also depends on the schedule you follow.
