Is Intermittent Fasting Really Worth It?

Experience Momentum's Registered Dietitians weigh in on the current trend of Intermittent Fasting.


Intermittent fasting is making the rounds as a health trend. We’ve had lots of questions lately about intermittent fasting, and decided to take a closer look at the evidence. Here’s the quick and dirty overview, as well as our two cents on which populations may and may not benefit from trying out this eating pattern.

What is intermittent fasting?

Fasting is abstaining from eating for a given period of time, and has been practiced by different cultures and religious groups for thousands of years. Intermittent fasting at its core is reducing the amount of time you spend eating. There are several different styles of intermittent fasting, ranging from only eating during specific time ranges (typically fasting for 12-16 hours and eating during an 8-12 hour window), to eating fewer calories a few days per week (typically having 1-2 days where you eat about 500 calories, and eating normally the rest of the week), to fasting for an entire day or more each week.

What does the evidence say?

Research on humans is relatively limited. Animal research shows that intermittent fasting may help lower cholesterol, triglyceride levels, and blood pressure, as well as reduce the spread of certain cancers and help improve insulin sensitivity - although researchers note these effects may also be due to weight loss. Intermittent fasting may result in weight loss if individuals are consuming fewer calories overall by narrowing the amount of hours of the day they spend eating, though the amount of weight lost varies significantly in both human and animal studies. Essentially, since there is not a large amount of research on humans, more data is needed to arrive at conclusive results.

Who may benefit from intermittent fasting?

According to current research, elite athletes and figure competitors may benefit from intermittent fasting. Again, as research in humans is relatively limited and data from current studies is inconclusive, we don’t recommend intermittent fasting as a weight loss technique.

Who should avoid intermittent fasting?

Pregnant or nursing women, those who have had or do have eating disorders, and folks with type 1 diabetes would be advised to avoid intermittent fasting.

Ask the RD's – our two cents

Our nutrition philosophy is grounded in evidence - since research on the effects of intermittant fasting in humans is so limited right now, we do not advocate intermittent fasting as a weight loss technique. We do advocate listening to your body’s hunger and fullness cues and fueling yourself accordingly throughout the day, as this has been shown in research to be beneficial for both weight loss and improving overall health. However, if you are feeling curious about experimenting with intermittent fasting to see how fueling your body in a different way affects your energy and mood or fuels the activities you love, we recommend meeting with our Registered Dietitians to discuss how to best implement intermittent fasting safely.

A final thought

Balanced nutrition plans, whether they include fueling yourself more frequently with smaller meals or less frequently with larger meals, should always include mindfulness around the quantity and quality of fuel you choose, paying attention to how the foods you choose make your body feel, incorporate movement you enjoy, and be sustainable for a lifetime.