By the time I post this, it will be over.

Before you even ask, at the end of this post is a link dump to some of the research supporting a periodic, extended fast for cancer prevention. Read these at your leisure – I tried to supply a mix of scientific papers with more accessible articles and interviews.

In August of 2018, when the honey and I first began to discover the benefits of fasting (IF: intermittent fasting, EF: extended fasting, TRE: time-restricted eating, ADF: alternate day fasting), we embarked on a 7-day fast. We opted to include coffee with butter/cream and coconut oil, and bone broth. We have since learned that the protein in the bone broth might diminish the effect of fasting, and of course the calories in the coffee prevented it from being a true, zero-calorie fast.

Another year has rolled by, and we have just completed what we now see as our annual 7-day fast. We mixed in some water only days with coffee-with-cream days.

Since this post is already link-heavy, I will simply describe what our experience was like, and will leave our regular fasting schedule, and the science behind it, for another day.

Day 1 – We fast regularly one day per week. In the fasting universe, this is referenced by how many hours are spent fasting.. For example, our usual pattern is one 42-hour fast per week. That means dinner on a Monday around 6, fasting on Tuesday, and eating again on Wednesday, midday. So today is no different than what we’ve been doing for over a year. Are we hungry? Comes and goes. We stay busy, stay hydrated, and think about what we’d like to break our fast with.

Day 2 – A good day at Freethought Farm. We stayed busy with tasks and didn’t feel too much hunger. I had a lovely walk on the Greenway with a bestie who is also a faster, so we enjoyed talking about what we’re each learning about fasting and nutrition. We had electrolytes and an abundance of water.

Day 3 – This seems to be the day for most fasters that it gets a little easier, and that is true for us too. Hunger comes in waves, so we drink a little water, go for a walk, make a phone call, etc, and the sensation passes. It’s not cumulative – we don’t feel hungrier and hungrier and hungrier.

Day 4 – If you research intermittent fasting at all, an important component of every plan includes consuming electrolytes: sodium, potassium, calcium, magnesium. We have both a homemade recipe, and commercial drops we use in water. Especially when you add in outdoor exercise in the heat, replacing electrolytes is absolutely critical.

Day 5 – Now we’re beginning to think about what we’ll eat to break the fast. We have a list of things we get hungry for (sometimes that helps when you get a little obsess-y thinking about food). It also helps for us to review the books and blogs I have posted below, and to visit a couple of Facebook pages we follow for inspirational stories from other people who incorporate the keto and IF lifestyle.

Day 6 – Almost there. Our sleep has improved, as have the other markers we measure daily – blood pressure, ketones, weight, mood, energy, performance, focus. We measure this whether we’re fasting or not, so it gives us the opportunity to compare. We have continued our regular workout schedule (6x week), and have recorded our results for those as well.

Day 7 – We made it! We don’t plan to do this again until next year. We are excited about breaking our fast, we both feel mildly euphoric (unless that’s an oxymoron), and looking forward to eating!

Breaking the Fast: We began with a small salad, then progressed to a medium rare ribeye with roasted broccoli and every bite was better than the one before. We’re glad not to do it again for another year, but we like what the exercise of extended fasting does for our appetite, our patience, our enjoyment of food, and potentially, our long-term health.

UCSF Osher Center for Integrative Medicine

Unlike CR, fasting induces changes associated with cellular protection to actually protect against weight loss initially and increases protection from oxidative stress.  Fasting results in a more significant drop in insulin levels, as well as an increase in insulin sensitivity in a shorter amount of time compared to CR.  Given that insulin levels play a role in cancer risk, these differences are potentially clinically important.

Podcast: The Quantified Body, with Dr. Thomas Seyfried, author of Cancer as a Metabolic Disease

All cancers can be linked to impaired mitochondrial function and energy metabolism. It’s not a nuclear genetic disease. It’s a mitochondrial metabolic disease… therapeutic ketosis can enhance mitochondrial function for some conditions, and can kill tumor cells.

Confessions of a Supply-Side Liberal, Miles Kimball, Eaton Chair of Economics, CU Boulder

If I were ever diagnosed with cancer, the first thing I would do would be to begin fasting immediately; my hope would be to slow down the progress of the cancer during the time it took to develop a more conventional treatment strategy for my cancer. I would also do my best to try to convince my cancer doctor to read Thomas Seyfried’s book in the hope my cancer doctor might get some good ideas for improving the treatment strategy.

Fasting Cycles Retard Growth of Tumors and Sensitize a Range of Cancer Cell Types to Chemotherapy

This is a link to the paper itself, and I didn’t want to pull a quote from the research, but here is part of the abstract:

The therapeutic potential of fasting would be even greater if it also increased the death of cancer cells. Here, we tested this possibility by studying the effect of fasting on cancer cell survival in the presence or absence of chemotherapeutic agents.

Interview with Dr. Jason Fung, author of The Complete Guide to Fasting

Apoptosis, which is also known as “programmed cell death”, is when cells commit suicide. It sounds kind of macabre, but it’s essential for good health. The cells of the body are like cars. When they get too old to be repaired they need to be destroyed to make way for healthy new cells – up to 70 billion every day. Not all cars need to be scrapped, though. Sometimes you can replace the parts, and this is where autophagy kicks in. The word derives from the Greek ‘auto’ (self) and ‘phagein’ (to eat), so literally means ‘to eat oneself.’ It’s when a cell doesn’t die, but replaces the worn out ‘sub-cellular’ parts with new ones. Autophagy is a form of cleansing: the process of breaking down and recycling cellular components when there’s no longer enough energy to sustain them. Once all the broken-down parts have been cleansed, new tissues and cells are built to replace the old ones. So, our bodies are in a constant state of renewal, but when these processes are hijacked, unwanted cellular bits build up and diseases such as cancer occur. Increased levels of glucose, insulin and proteins all turn off autophagy, and it doesn’t take much. Even as little as three grams of the amino acid leucine can stop it. But fasting turns these cleaning mechanisms on.

Fasting-like diet turns the immune system against cancer

“It may be that by always being exposed to so much food, we are no longer taking advantage of natural protective systems which allow the body to kill cancer cells,” Longo said. “But by undergoing a fasting-mimicking diet, you are able to let the body use sophisticated mechanisms able to identify and destroy the bad but not good cells in a natural way.”

Fasting and Caloric Restriction in Cancer Prevention and Treatment

Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer.

Next post: We both had the Coronary Artery Calcium scan, which might be the most important indicator for heart health. Stay tuned for our results!

Thanks for reading!