Fasting the Keto-Green Way

I have been practicing fasting for years now and view it as part of my ongoing commitment to a healthy lifestyle. Because of its scientifically proven weight-loss results and other significant health benefits, I have specifically incorporated a form of it called “ intermittent fasting ” into my Keto-Green ™ diet and lifestyle program.

In fact, I have learned (the hard way) to only make major and important decisions in this keto-green fasting state!  I won’t tell you what some of those bad decisions were that I made under brain fog… but I can tell you, I learned my lesson!

Intermittent fasting restricts “when” you can eat, versus “what” you can eat.

There is no intentional calorie restriction associated with intermittent fasting. Think of intermittent fasting as simply shrinking your eating window! In my programs, I recommend fasting 13 to 15 hours between dinner and breakfast on a regular basis.  Personally, I use intermittent fasting in a 15/9 pattern  or a 15/9 time-restricted feeding interval. This means the person’s “feeding window” each day is one approximately 9-hour period; you then fast the other 15 hours, typically starting right after dinner. (Of course, we’ll start with a more-doable goal of something like a 12-hour fasting period and build up from there and you can even extend to 16 hour fasting window.)

Fasting during the holiday

hormonal balance

I routinely do intermittent fasting, but on occasion will also fast for longer periods – for example, during Lent. Many religions have practiced fasting over the ages. It is a powerful form of both achieving heightened spirituality and testing one’s self-discipline, and it can be quite cleansing for body and soul. Easter is a holiday known for faith and reflection; the 40 days before Easter are a time to memorialize death and resurrection by choosing to fast out of obedience or penance.

On most Sundays, I try to do an all-day fast or just a single-meal fast (and of course I’ll make that single meal a Keto-Green meal ...mostly).

Fasting in science

Fasting has been shown to improve biomarkers, those biological indicators of our medical state – things like blood pressure and cholesterol and glucose levels that might signal how susceptible we are to problems such as cardiovascular disease, diabetes and breast cancer. Fasting can also increase metabolic function, improve insulin sensitivity , reduce oxidative stress, moderate cravings, and help people become more-efficient fat burners.

While initially viewed as a mechanism for improving athletic build and increasing sports performance, research has shown fasting can also be a significant weight-loss tool, as well as a potential way to influence gene expression in a manner that promotes longevity.

Sounds good, right? But fasting can sound a little intimidating when you first hear about it or decide to try it out. There are some extreme forms of fasting, in terms of the amount of time that you don’t eat (days!), what you are allowed to eat (some regimens only allow water, while others are calorie restricted and still others are more detox/cleansing focused), and what supplemental nutrients you may need to take. There are literally hundreds of different fasting options out there – and some in fact can be harmful.

So what’s the best way for women over 40 to fast?

I chose intermittent fasting as part of my Keto-Green program because it supports ketosis, a metabolic process during which your body is in fat-burning mode (and when a lot of health benefits kick in), while not causing the weight swings seen in many calorie-restricted diets – that’s the yo-yo effect we see when women, especially those over 40, lose weight but gain it back fairly rapidly. It’s often referred to as “rebound weight gain.”

Looking at results from clinical trials , while calorie restriction (in the 20%-50% range) was better for initial weight loss, intermittent fasting was deemed superior because, comparatively, it produced less rebound weight gain, as well as less metabolic slowdown.

The good news about intermittent fasting is:

  1. It’s a type of fasting that is relatively easy to implement (we start with a fast of approximately 12 hours and then continue to lengthen it).
  2. It’s a type of fasting that women can stick with and even embrace.
  3. You don’t have to buy anything! That means none of the special pre-packaged, low-calorie foods that other types of fasting require you to purchase.
  4. There is a lot of research that shows intermittent fasting to be both effective and safe.

The ideal fast should support the ideal diet!

Most fasts are used in conjunction with other dietary interventions. A fast should be supportive of and integrated into whatever healthy diet you are trying to maintain.

In my Keto-Green program, for example, women focus initially on getting alkaline (a very healthy state for our bodies to be in!). They follow ketogenic principles to get into ketosis , and once they’re enjoying the benefits of a keto-alkaline diet, they add intermittent fasting. When women fast between dinner and breakfast, their bodies need to find energy reserves beyond stored glucose. Since the body can store reserves for only about 24 hours, the intermittent fasting will drop glucose storage levels way down; your body will then burn fat instead!

Of course, women need to remain focused on a Keto-Green diet when they are in their feeding window – certainly one can’t eat donuts and drink sugary soda all day long and still expect to gain benefits from intermittent fasting! Having said that, intermittent fasting does not restrict calories. You just need to maintain the same ratios on your Keto-Green “plate” during your feeding window.

Healthy plate ratios


Interestingly, research has found that people on an intermittent fast often eat less (consuming fewer calories), even without intentional calorie restriction.

What makes a healthy “plate ratio” on a Keto-Green diet?

  • 20% healthy protein (organic eggs, grass-fed beef, etc.)
  • 56%-70% healthy fats
  • Saturated fats such as grass-fed butter, coconut oil and ghee
  • The healthy omega-9 fatty acids that can be found in olive oil, avocados (my favorite!), sprouted nuts and seeds, and almonds
  • The omega-3 fatty acids found in flax seeds, chia seeds and salmon
  • 5%-10% healthy carbs (or, said another way, a diet very low in unhealthy carbs!)

Women over 40 can incorporate intermittent fasting into their Keto-Green diets to support ketosis, as well as to achieve the many incremental health benefits that are associated with fasting, such as regeneration of our immune systems, improved insulin sensitivity , reduced blood glucose, the purge of cancer cells, and activation of something called autophagy .

Always remember, the best diet is not a short-term meal plan or just a fast, but an entire lifestyle, including exercise, stress management, and focus on your gut health and toxicity. It’s time to kick-start your healthy journey and consider a Keto-Green lifestyle!


    P.S. My Detox Bundle is a great way to detoxify and cleanse your body and your soul.

    Join me and my tribe on my 21-Day Detox Challenge !

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    Dr. Anna Cabeca

    Dr. Anna Cabeca

    Certified OB/GYN, Anti-Aging and Integrative Medicine expert and founder of The Girlfriend Doctor. During Dr. Anna’s health journey, she turned to research to create products to help thousands of women through menopause, hormones, and sexual health. She is the author of best-selling The Hormone Fix, and Keto-Green 16 and MenuPause.

    Learn more about my scientific advisory board.