Intermittent Fasting, or IF, is the latest craze in the health & wellness industry. Why? People are using it to lose weight, improve their health, and simplify their lifestyles. Studies are even showing the benefits IF may have on your brain & body and may even help you live longer. But how do you do it and is it safe?
What is Intermittent Fasting?
Many diets tell you what to eat. Intermittent fasting tells you when to eat. In that respect, IF can be described as an eating pattern. With intermittent fasting, you only eat during a specific time. Fasting for a certain number of hours each day or eating just one meal a couple days a week, can help your body burn fat. And scientific evidence points to some health benefits, as well.
Intermittent Fasting Plans
The various ways of doing intermittent fasting all include splitting your day or week into eating and fasting period. During the fasting periods, you eat either very little or nothing at all.
These are the most popular methods:
- The 16/8 method: The simplest and most popular method, aka Leangains protocol, involves skipping breakfast and restricting your daily eating period to 8 hours, such as 1–9 p.m. Then you fast for 16 hours in between.
- Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day.
- The 5:2 diet: With the 5:2 method, you consume only 500–600 calories on two nonconsecutive days of the week, but eat normally the other 5 days.
What Can I Eat?
During your fasting periods, you’ll want to focus on water and zero-calorie beverages such as black coffee and tea.
During your eating periods, you can “eat normally” but that’s different for everyone. We recommend eating as clean as possible during your eating periods. Give your body the fuel it loves and knows how to digest.
Intermittent Fasting and Weight Loss
Weight loss is usually the main reason people try intermittent fasting. By reducing your calorie intake, and eating fewer meals, intermittent fasting should cause weight loss as long as you don’t compensate by eating much more during the eating periods.
Studies show that intermittent fasting can be a very powerful weight loss tool. A 2014 review study found that this eating pattern can cause 3–8% weight loss over 3–24 weeks, which is a significant amount, compared to most weight loss studies (1). According to the same study, people also lost 4–7% of their waist circumference, indicating a significant loss of harmful belly fat that builds up around your organs and causes disease (1).
Keep in mind, the main reason intermittent fasting is effective is because you eat fewer calories overall. If weight loss is your ultimate goal, you’ll still want to track your calories to ensure you’re in a deficit. If you overeat or binge during your eating periods, you’re less likely to lose weight.
Intermittent Fasting Health Benefits
Like most fads, research for intermittent fasting is still in the early stage. Ultimately, studies are showing powerful benefits.
Here are the main health benefits of intermittent fasting:
- Weight loss
- Lower Insulin resistance
- Reduction of overall inflammation
- Improving heart health
- Cancer prevention
- Improving brain health and function
Safety and Side Effects
Intermittent fasting isn’t for everyone. Whether you’re trying IF for weight loss/management or you’re looking to treat chronic conditions, you should always check with your primary care practitioner first. Populations who should avoid intermittent fasting include children under 18, pregnant or breastfeeding women, people with type 1 diabetes, and those with a history of disordered eating.