Intermittent Fasting: Why is it Popular?

What is Intermittent Fasting?

Fasting practices have been frequently used as religious or cultural traditions since time immemorial, but have vastly grown in popularity in recent years for health promoting effects and weight loss remedies. Intermittent fasting (IF) is the practice of refraining from food and beverage (excluding water) consumption for extended periods of time, usually ranging from 16 to 48 hours, but can be accomplished in as little as 12 hours. During this time, little to no energy intake occurs. IF should not be confused with periodic or prolonged fasting, which includes fasting practices lasting from two days to 21 days or more.

IF practices vary; for example, some individuals restrict food and beverage intake two days per week or every other day, while others allow themselves an eight-hour eating window each day and fast for the remaining 16 hours. Also, some fasting plans only allow water to be consumed as a beverage, while others allow black coffee, black tea, and other zero calorie liquids.

Benefits of Intermittent Fasting

While  some individuals practice IF to achieve weight loss, many also practice IF to obtain health benefits related to the prevention, management, or treatment of chronic diseases. Studies have shown that IF can induce weight loss in normal and overweight individuals, but also may improve insulin sensitivity, blood pressure, and oxidative stress independent of weight loss. Other studies have shown IF can improve cardiovascular disease risk factors including resting heart rate, blood pressure, cholesterol, triglycerides, glucose regulation, insulin resistance, waist circumference, obesity, and metabolic syndrome. In addition, IF may reduce inflammation markers and oxidative stress associated with atherosclerosis.

Emerging research also suggests other conditions that may benefit from an IF regimen may include: the prevention or treatment of various types of cancer; the delay of the onset and/or progression of Parkinson’s and Alzheimer’s disease; improved symptoms for other health conditions like asthma, multiple sclerosis, and arthritis; and last but not least, slowing the aging process and increasing life span.

Challenges and Cons

Individuals who have a history of eating disorders, are pregnant or trying to get pregnant, breastfeeding, have type 1 diabetes, have hypoglycemic tendencies in general, require food intake with medication, are underweight, or are adolescents at an active growth stage should avoid IF, unless advised by their physician.

IF can produce adverse effects such as a tension headache, which may be caused by hypoglycemia, dehydration, or caffeine withdrawal. Other potential adverse effects may manifest as fatigue, hunger, coldness, irritability, inability to concentrate, bad breath, and constipation; however, these should subside within one month of beginning IF.

It is important to note that similar weight loss can be achieved by other dietary plans such as a keto, paleo, calorie restriction, or a Mediterranean diet, among others; therefore, individual lifestyles and preferences should play a key role in determining which dietary pattern is the best fit.

Implementation Tips

1. Start slow and gradually increase the fasting period, while concurrently reducing the time window of eating each day.

2. Adhere to a healthy eating plan during non-fasting hours and include plenty of fruits, vegetables, and whole-foods. Limit or avoid processed food, added sugar, and alcohol.

3. Work with a qualified nutritionist to determine the best course of action to take, including the development of a long-term nutritional plan that ensures efficacy and safety. 

Conclusion

In 2019, “intermittent fasting” was the most googled diet in the world, indicating rapid growth in popularity. So why is it so popular? Because intermittent fasting has become widely recognized as an easy and effective strategy for weight loss and can aid in the prevention or treatment of many chronic diseases, including diabetes, cardiovascular disease, metabolic syndrome, cancer, and more. For optimal health and wellness achievement, it is best to use IF as an adjunctive therapy to healthy eating patterns during non-fasting times.

References:

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