Cellular Spring Cleaning: Intermittent Fasting for CFS

Learn how fasting can improve cell and mitochondrial function but clearing away damaged cells through autophagy.

Do you ever wish that you could give your cells a healthy dose of Spring cleaning? You can.

Intermittent fasting has been crucial in my long-lasting CFS recovery. Simply by avoiding meals for 12-18 hours periodically I have been able to stave off relapse and even “bad days.” How can this be?

Fasting has been used therapeutically for centuries. Throughout history, every culture or religious group institutes some type of fasting as part of spiritual practice. Modern fasting is more popular in Europe and is taught as a therapeutic tool in post-graduate education. Periods of fasting improve symptoms in patients with autoimmune conditions, particularly rheumatoid arthritis (1). In Germany, fasting is referred to as “heilfasten,” which means healing fasting or fasting cure (2).

Preliminary research indicates that intermittent fasting may reduce the risk of type 2 diabetes and cardiovascular disease and have beneficial effects in cancer treatment. Additional clinical trials have explored fasting therapy for osteoarthritis, fibromyalgia, hypertension, chronic pain syndromes, migraine, psychological well-being and mood-enhancement (2).

How it Works

With fasting, the cell switches over to protective mode—genes related to aging (sirtuins) are turned off while genes for repair are turned on (3). Fasting triggers apoptosis (programmed cell death) of the cell’s mitochondria. In CFS, chronic oxidative stress wrecks havoc on the mitochondria leading to severely depleted energy capacity. During a fast, the already damaged mitochondria throw in the towel (a process known as mitophagy) to make room for new and improved mitochondria (a process known as fission).

A second powerful way that fasting improves cellular function is through creation of ketones. In a fasted state, the body pulls on stored glucose (glycogen) for fuel. However, if one is following a low carbohydrate diet and has fasted for 12-18 hours, glycogen stores are vastly depleted. As an alternate fuel the liver starts to utilize fats to create ATP through a process known as beta-oxidation. The result is the production of ketone bodies like b-hydroxybutyrate and acetoacetate. Many studies have found that b-hydroxybutyrate is a potent antioxidant and regulator of gene expression (4). With elevated levels of b-hydroxybutyrate, several key genes are stimulated to protect against oxidative stress. It is also neuroprotective and enhances neuronal function. This is of particular importance in the brain where oxidative stress can damage neurons and lead to neuroinflammation (encephalitis) or brain fog (5).

Summary of Cellular Effects

  • Turns on apoptotic genes

  • Leads to mitochondrial autophagy

  • Reduces oxidative stress by stimulating glutathione production

  • Inactivates NF-kB which reduces production of reactive oxidative species

  • Promotes creation of new mitochondria through fission

  • Increases mitochondrial defenses

  • Increases ketone bodies which directly reduce oxidative stress & neuroinflammation

The Cat Cell Mitochondria

How to Do It

Fasting is not starvation! When done properly, you should not feel hunger or energy drained. The simplest way to begin a fasting protocol is to consume all of your meals for the day within a 6-8 hour window. During this time choose nutrient-dense foods, healthy fats, and a modest amount of protein. This can be accomplished by eating an early dinner—with the bulk of the fasting time occurring during sleep—followed by a late breakfast around noon.

You can still consume during intermittent fasting. It is especially important to continue to drink adequate water. Vegetable or bone broths and herbal teas may also be consumed. Another trick is to eat healthy fats during the fasting period, as they will contribute to the amount of ketones in the system and reduce potential muscle breakdown. Choose saturated fats (avocado, coconut oil/butter) or medium chain triglycerides (grass-fed butter) which are easily converted to ketones without taxing metabolic pathways. These fats can be blended into teas or coffee for a satisfying treat during the fast. Avoid carbohydrates (sugars) and long-chain fats like polyunsaturated fats from nuts, seeds, olive oil, as these require energy to be broken down by the body.

Occupy your mind while fasting by busying yourself with an activity: watch a film, read a book, listen to music, take a nap, call a friend. Boredom tends to promote the need to eat, so stay preoccupied and the fasting time will pass by quickly without much difficulty.

There is no set protocol for how often to fast. Experience will tell you what works best for you. Fasting 1 or 2 days per week is a good starting point (6).

Words of Caution

Intermittent fasting may be counterproductive in those who have unstable blood sugar (hypoglycemia), adrenal fatigue, or thyroid problems (6). I would encourage stabilizing these conditions first before embarking on an intermittent fasting protocol.

Need help with intermittent fasting? Consider a consultation with Dr. C.

Another point of caution is not to fast for too long! Fasting beyond 24 hours leads to protein breakdown and loss of lean mass. When in doubt, ask your doctor.


1  Wilhelmi de Toledo, F. et al. (2013) Fasting Therapy – an Expert Panel Update of the 2002 Consensus Guidelines Forsch Komplementmed. 20:434–443.

2  Boschmann, M & Michalsen, A. (2013) Fasting Therapy – Old and New Perspectives. Forsch Komplementmed 20:410–411.

3  Hirschey, MD, et al. (2013) Suppression of Oxidative Stress by β-Hydroxybutyrate, an Endogenous Histone Deacetylase Inhibitor. Science. 339(6116): 211–214.

4  Merksamer PI, et al (2013) The sirtuins, oxidative stress and aging: an emerging link. AGING 5(3).

5  Michalsen A, Li C, Kaiser K, Lüdtke R, Meier L, Stange R, Kessler. (2013) In-Patient Treatment of Fibromyalgia: A Controlled Nonrandomized Comparison of Conventional Medicine versus Integrative Medicine including Fasting Therapy. Complement Alternat Med. 2013:908610. 

6  Longo, VD & Mattson, MP (2014)  Fasting: Molecular Mechanisms and Clinical Applications. Cell Metabolism. 19:181-192.