Intermittent Fasting with the SlimFast Plan

Intermittent Fasting is a way of eating that encourages cycling between periods of fasting and eating, with a focus on when you should eat. Registered Dietitian and SlimFast Plan Consultant, Maryann Walsh explores two ways (16:8 or 12:12) to practice intermittent fasting with the SlimFast Plan.


A growing body of research supports that intermittent fasting may be a safe and effective way of eating for many, especially those who are seeking weight loss. While more research is required, fasting may have a positive effect on one’s immunity and on lowering inflammation in the body1,2.

Contrary to what you might think, fasting does not mean you can’t consume anything at all. There are several things you can consume during a fasting period: Water, black coffee or tea or sugar-free drink mixes like SlimFast Keto Ultra Hydration are all great options to keep you hydrated. Also, because MCT oil is digested and converted to energy quickly and efficiently without affecting blood sugar, it can be used during the fasting period.

You can practice intermittent fasting while following a variety of dietary approaches, however, those following a ketogenic diet may find that intermittent fasting is a natural fit. Research has shown that the Keto diet has been shown to suppress the hunger hormone, Ghrelin3 which may make it easier to stick to an intermittent fasting regimen.

One of the most popular ways to fast is the 16:8 pattern. This involves consuming your total calories for the day within an 8-hour time frame while fasting for the remaining 16 hours of the day. If 16 hours seems like too long of a time frame for you to go without eating, then you can also try starting with a 12:12 pattern, which would allow for a 12-hour time frame where you consume your calories and a 12-hour time frame where you are fasting. Keep in mind, the time you spend sleeping is part of these fasting hours, so starting with 12 hours of fasting may not be too difficult if you begin fasting 2 hours before getting 8 hours of sleep and you don’t consume any food 2 hours after waking up.


Why Intermittent Fasting May be Worth Trying Out

From a behavioral standpoint, restricting your meals and snacks to a strict time window may naturally decrease your overall calorie intake and cut down on night-time snacking (“kitchen is closed” mentality), which can aid in weight loss.

One study showed a decrease in fat mass in those who did a 16:8 IF versus those who ate the same number of calories without time restricted feeding4. Another study showed a significant weight change in those who practiced time restricted feeding versus those who did not.5

As mentioned above, a ketogenic diet has been shown to suppress the hunger hormone, Ghrelin, so this may be an effective approach for those who have a difficult time with hunger while trying to follow a weight loss plan. This process makes it easier to stick to an intermittent fasting pattern and even when appetite suppression isn’t as effective, many may enjoy having a window of restriction to more easily stay within their macro or calorie goals.3


How to Add Intermittent Fasting to the SlimFast Plan

It is absolutely possible to incorporate an intermittent fasting plan into the SlimFast Keto Plan. For women following the SlimFast Keto Plan, the recommendation is to consume approximately 1,200-1,300 calories and for men the recommendation is to consume approximately 1,600-1,700 calories per day. As part of a 16:8 or 12:12 fasting regimen, you just consume those calories within your 8 or 12-hour eating period.

Just like the SlimFast Plan, incorporating a 16:8 or 12:12 fasting plan is as easy as 1-2-3!

Choose a 12 or a 16-hour fasting window (that includes the hours when you sleep).

Experiment with an eating or feeding time frame that makes the most sense for you, some examples:

  • 9 am to 5 pm or 9 am to 9 pm
  • 10 am to 6 pm or 10 am to 10 pm
  • 11 am to 7pm or 11 am to 11 pm
  • 12 pm to 8 pm or 12 pm to 12 am (if you’re a “night owl” or you work late shifts)

You can plan your schedule however it best works for you. Below is an example of what a 16:8 day could look like on the SlimFast Keto Plan:

Meal Planner IF

Plan what you will consume during your fasting period.

Stay hydrated with the SlimFast Keto Ultra Hydration drink mix and curb hunger by adding SlimFast Keto MCT Oil or flavored Fat Bomb Shot to a cup of black coffee or tea.

If you decide that you want to give intermittent fasting a try, as with any other dietary plan, always make sure to check with your doctor first, especially if you are nursing, pregnant, under the age of 18, have a medical condition or are on any medications.




A consultant of the SlimFast Plan, Maryann is a Registered Dietitian with Bachelor of Science degrees in Biological Sciences and Dietetics and a Master of Food and Nutrition. She has extensive experience working with clients of all ages and from all walks of life, helping them to achieve their wellness and weight-loss goals.  Learn more about Maryann.