Our Ground Rules

The Manifesto

A Jet Fuel Fast (JFF) is a ketogenic “assisted” fast that combines fasting principles with available technology and supplements to make the JFF as comfortable and sustainable as possible. While many excellent practitioners in the fasting space have recommended these agents on an “as needed” basis, Jet Fuel Fasting is the first program that brings the use of an assisted fasting “comfort kit” to the forefront.

• Why am I here? This space is to keep myself honest and share all of the things that seem safe and testable.
• Why call it Jet Fuel Fasting? Because jet fuel burns cleanly like ketones, and it sounds better than Have Some MCT Powder or Ketones If You Feel Too Miserable Fasting.
• Am I qualified? I’m not a health practitioner. I’m a US Navy Intelligence Officer with a few decades of experience gathering, processing, and disseminating information to military operators and decision makers. I was also a school teacher (algebra) for 10 years. I have 40,000 hours of experience sifting through BS for clear, actionable approaches. I’m not qualified to give you medical advice, but I am qualified to review information, make assessments, and present it to you. I want to share my reasoning and approach as one example of how you can use your own reasoning to solve for your own needs.

What I really want is to make each of you into personal experimenters. We’ll walk through how to conduct a personal, N=1 experiment, capture the data, and then iterate the next round for greater clarity or success. I will share the results of my personal testing and tell you what works for me. I don’t guarantee you’ll have the same results. Yours may be better, or not as good. Our bodies and lives are too unique and intricate for those sorts of promises. Beware of snake oil salesmen.

What Are You Trying To Achieve? Hmm? What is it?

With Jet Fuel Fasting, and with ANY “should I try?…” health question, the question is “What are you trying to achieve?” Here’s what I’m trying to achieve, in this order.

• My most important goal is to reduce my risk of cancer. I have a strong prevalence of cancer in my family and two young children to raise. Early in 2020 my mother passed unexpectedly from cancer at the age of 59. She was fit, healthy, and in the prime of her life. It came on like a lightning strike. I may still get cancer, but I don’t mind being a little hungry for a few days a month if there’s a chance it may reduce my risk. See Nasha Winters, Thomas Seyfried, Dominick D’Agostino. 
• My most immediate goal is brain energy. In 2013 I began experiencing cognitive problems. I say “cognitive problems” instead of “brain fog” because brain fog sounds like something that happens to someone who can’t always find their keys, or forgets a word. I couldn’t drive, and sometimes couldn’t hold a conversation. This was terrible and frightening for me and, I’m sure, unpleasant for my family. Not going to tell a long story here, but of course I went to every sort of specialist and also alternative medicine practitioners. I tried a lot of meds, supplements, and lifestyle changes. There were never any clear answers and none of these things really helped. I’d played around with a ketogenic diet in the past. Basically one day I said “F-it, I’ll just not eat for a week.” And it was awesome. I could think again. I was back. Since there wasn’t much that helped other than a ketogenic diet, I concluded that whatever is wrong with my brain is somehow related to an energy problem (my brain needs ketones to function because it doesn’t use glucose like it should) or an inflammation problem (the ketogenic diet reduces inflammation enough for my brain to function). My ketogenic diet has vastly improved my quality of life. Using the Jet Fuel Fasting aids I describe here improves the effect.
  • A quick digression: These ketone aids have been helpful for me even when not fasting, sometimes to maintain higher ketone levels and have a more liberal, but still ketogenic, diet. For example, say my maintenance intake with “strict” keto is 85g protein, 20g carbs, and the rest healthy fats (AKA anything other than seed oils). With light daily exercise, this allows me to maintain ketone levels of 1.5 mmol or higher, which for me corresponds to the best overall feeling of wellness, energy, and mental clarity. But on some days I simply feel like eating more protein and more vegetables, or maybe it’s hard to get enough fat in so I eat more protein. This is common when travelling when it’s harder to control what food you have available; even without sugar or starch, extra protein and carbs can drag my ketone levels down. I usually settle around 0.7 mmol of ketones if I’m not careful with protein. Well 0.7 mmol is a perfectly fine place to be for most people. Sometimes it’s fine for me. But if I feel the old cognitive issues creep in, I know I need to add some ketones RIGHT THEN. I’ll also begin to trim back on the protein and carbs in order to get my ketones up naturally. *Note: At no point am I using exogenous ketones or MCT to compensate for a standard (even “low carb’) non-ketogenic diet.
• Maintain my metabolic flexibility and avoid chronic disease. I’ve never been diabetic and don’t have heart or cerebrovascular disease. I don’t want them.
• Reduce body fat/maintain my weight. Okay, my first two were about reducing my risk of death, but let’s be honest; keeping body fat down takes up most of my mental energy. I’m a middle aged mom fighting the middle aged spread. Of course I drink my coffee black and skip meals.

So what are YOU trying to achieve? One of the above goals? Something different? How do you want to get there? What biological mechanism do you want to fool with? What lever do you want to pull?

Jet Fuel Fasting Basics

Work from Valter Longo (no affiliation) has proven (in a real science sort of way) that one need not water fast for the benefits of autophagy, immune reset, neuro-regeneration, and metabolic improvement. Proof is a charged concept. What I mean here is that he’s performed multiple, repeatable, large Randomized Controlled Trials in multiple species, to include humans, that had large and significant measurable outcomes which persisted over time. Longo’s making money too, of course. His patented product ProLon is a first of its kind approach that delivers a package of processed food that has been tested in humans to mimic his research model. The ProLon protocol is a 800-1000 calorie per day low protein diet that mimics fasting. His book is the first place I heard the term “Fasting Mimicking Diet,” or FMD.

Additionally, Dr. Robert Atkins wrote about Fat Fasting in his book the New Diet Revolution. Atkins advocated up to 1000 calories a day of mainly fat (again, little protein) to jump-start deep ketosis and weight loss.

Originally I was inspired by Longo but did my own ketogenic version of the FMD. My protocol was five days at 800 calories per day, during which my mini-meals were things like vegetable soup with olive oil, lettuce with olive oil, and maybe a few pecans. Everything was weighed and/or measured, of course. I tracked my ketones, first with urine strips and later with a Biosense breath meter. My results were pretty great. Each cycle I’d lose a pound or two and feel freaking awesome. The high ketone levels seemed to reduce my overall inflammation. My mind was clear. Buuuuuuut…. Five days is a long time, and I started to feel like it was affecting my muscle mass. I’m not a bodybuilder or anything, but I have a good amount of muscle for a 40-something mother of two. I didn’t want to lose any of it. So I tried cutting the same protocol down to three days. But it wasn’t enough to get the big whoosh of disappearing inflammation, nor was it enough to lose weight. So I went back to the drawing board and eventually settled on what I’ve come to call Jet Fuel Fasting.

Jet Fuel Fasting unashamedly stands on the shoulders of these giants, with a few notable differences. Here’s the basic idea: First, we accept that energy restriction is good, and may help improve glucose metabolism, provide the benefits of autophagy, and assist with weight management. In Jet Fuel Fasting, we seek to reap all of these benefits, but add the occasional energy or hunger management aid.

1. Using modern technology and supplements that burn directly as ketones, such as MCT oil, MCT oil powder, and ketone salts. BUT, keep additional energy as low as possible (instead of a set level like 800 calories). This will be different in each person and may change over time with subsequent Jet Fuel Fasts, hormonal state, illness, stress levels, sleep quality, etc.
2. Using caffeine, GLP-1 enhancing mate tea, supplements (mainly Acetyl L-Carnitine) and electrolytes (ketone salts also provide electrolytes) to additionally curb hunger and maintain a feeling of focus, calm, and energy.
3. Additionally, use light exercise to accelerate fat burning, release energy, and signal muscles to stick around.

NOT FOR YOU

Folks who should move on to another website:

• If you’re an experienced water faster, and that works for you without discomfort, I applaud you. You’re stronger than I am! You don’t have to read any further. Gin Stephens and other water fasting advocates will serve you better than I will. Good luck!
• If you’re looking for a quick fix. These don’t exist. Sorry.
• If you’re still eating a lot of carbohydrates, you’ll need to address that first. I’m assuming that, if you’re reading this, you are already in ketosis or low enough carb that you can get into ketosis easily. If not, stop here and go read the 30,000 other blogs that have already explained how and why to cut carbs. Then come back. 🙂

JUST TELL US HOW TO DO IT ALREADY!!!

Okay, okay, how does this work in practice?

1. Wake up and measure ketones and blood glucose. If you’re FREAKING STARVING upon waking you can add some MCT powder to your coffee or tea. Or simply eat it off of a spoon. (Don’t drink MCT oil on an empty stomach unless you have a colonoscopy scheduled that day. Save the oil for salad dressing.) But, if possible, have the coffee or tea black or just drink your water. Most folks that find my little page are already doing some sort of Time Restricted Feeding (TRF), so if you generally skip breakfast, do that now, as well.
2. When you get moderately hungry (usually when you’d have your first meal) or when you feel foggy (low brain energy), have one of the following:
   • Warm beverage with one scoop MCT powder (~80 calories)
   • Water with exogenous ketones, AKA BHB salts (~70 calories of energy per 8g, not always stated on the package)
   • Coffee or Tea
   • Yerba Mate (According to badass neuroscientist Andrew Huberman mate tea is a GLP-1 agonist, which can reduce hunger hormones independently of its stimulant effects. This is the same pathway that the blockbuster diabetes and diet medicine Wegovy acts upon.)
   • Water with salt. (Note, I was drinking Better Than Bouillon for a while, but noticed when wearing a continual glucose monitor that it spiked my blood glucose 25 points every time I had some. This is with 15 calories of bouillon. Weird.)
   • Anything else you can think of that doesn’t have calories.
   • *One thing I’ve played with is using a no/low calorie food as a carrier for MCT oil. For example, heating up some shirataki noodles and putting 1 tablespoon of MCT oil (120 calories) on them with some spices. Or a small lettuce-only salad with MCT oil, vinegar, and spices. I’m still trying to decide if it’s too much like “eating” and makes me hungrier later or if the feeling of solid fullness is simply satisfying and helpful. It doesn’t seem change my results though. I’d love to hear your experience.

3. Repeat this until bedtime, with the overall goal of using the caloric aids (MCT powder, MCT oil, and ketone salts) as little as possible, but enough to maintain comfort. My own favorite regimen is MCT powder in coffee around noon, ketone salts in a large water bottle, sipped on throughout the middle of the day, and then a MCT hot cocoa in the evening. (MCT powder, unsweetened cocoa powder, and a packet of stevia. Boil water in the microwave in a high sided mug, add the powders, and blend with a milk frother.)

4. Do this for one day or more. I’ve done up to five days, but don’t do that anymore because, as stated, I worry about muscle loss. Note that during a multiple day JFF, you’ll likely find that you need the fasting aids (MCT oil or powder, ketone salts) less often. So maybe you do a three day JFF. On day one perhaps you use 500 combined calories of assistance and on days two and three only 300 calories of assistance.

5. If not very overweight, you absolutely need to throw in feast days, during which you eat at or beyond maintenance calories. Metabolic adaptation (AKA slowing metabolism from chronic dieting) is real. If you’re one of those crazy keto people (like me) then just eat more protein and fat. If you’re on a standard (but hopefully healthy) diet then just eat more of that.

Data, Measuring, and Tracking

We’re not going to “chase” ketones or numbers. We’re going to use them to chase results. We’re going to design experiments, test them, gather data, look at results, and iterate. Also, we’re going to use common sense and not hurt ourselves.

The best measurement I can ask you to take is to rate how your brain feels and how much physical energy you have. Then, if you’re geeky like me, you can try to correlate that to a ketone level so that you have a target during your Jet Fuel Fast.

When JFFing, make note of at what ketone level your hunger moves from insistent to irritating, and from irritating to unimportant. For this you need a ketone meter. For example, at 0.7 mmol hunger waves (yes, it’s just a wave, it’ll pass) are tolerable for me. Once I pass about 1.5 mmol they’re easier. At 2.5 or higher there’s almost no hunger. For me, at 2.5 or higher I also need to be careful with my caffeine intake because I’m so jazzed up. Your mileage will vary, but once you know what ketone levels make you feel good while JFFing you have a target and can titrate your exogenous sources of ketones based off of that.

Some Sample Routines

My current favorite routine is Jet Fuel Alternate Day Fasting from Monday through Friday. So one day JFF (about 250 calories of ketone-inducing aids) followed by a day of JFF plus two protein rich meals (around 1000 calories total). Here the goal is to pulse protein every other day without getting out of the JFF mindset. I’ll do this for four days. This works out to two 42 hour JFFs. Like this:

• Rolling 42s
  • Day 1: JFF with two servings of MCT powder and one serving of ketone salts.
  • Day 2: Normal JFF morning (MCT coffee at noon, ketone salts in water to kill hunger and provide brain energy). Then a workout and a salad with protein around 2 PM (can use MCT oil for dressing), then lean steak, chicken, or fish for dinner around 7 PM. Around 1000 calories, 70-90g protein, the rest is Jet Fuel.
  • Days 3-4: Repeat days 1 and 2.
  • Day 5: Have a FEAST day that prioritizes protein. Try to get slightly above a full day’s calories. Metabolic adaptation (aka slowing metabolism) is real. Especially when you have less than 20 lbs to lose. Six months from now when you’re eating 1400 calories a day and still gaining weight, you’ll regret not having feast days to keep your metabolism healthy.

• Another approach could be Jet Fuel Fasting all day, workout, and then eat a big dinner like the One Meal a Day (OMAD) people. We can call this Jet Fuel By Day…
• Lately I’ve been experimenting with two days of JFF and then a few days of JFF with up to 50g of protein from lean sources.
• You could eat your normal diet for five or six days and then Jet Fuel Fast for one or two days.
• Here’s one I did recently: JFF day, JFF + steak dinner, JFF day, feast day with a big workout, JFF day.
• Like other fasting approaches, try to find things to do other than think about food: Drink stuff, listen to music, call a friend, plan a trip, take a shower or bath, read, exercise, watch TV, fold laundry, play with your kids, meditate, clean or organize the house, garden, sunbathe, or look at pictures.

Get it?

Should I exercise? What exercise do I do while JFFing?

Here’s my recommendation. Every day that you JFF you want to signal your muscles that they’re still needed. If you feel like lifting heavy, go for it. Aerobic exercise, AKA zone 2, AKA the “fat burning zone” is probably fine or helpful. Anaerobic and HIIT style exercise is probably not a great idea because your glycogen may be depleted and you’ll “bonk.” Then you’ll break down muscle tissue to generate more glycogen. No bueno.

I like to go on long walks or ride my bicycle. I wear a Garmin watch so that I can keep my heart rate in the Zone 2 range like Phil Maffetone. Also, I do a short but intense workout that takes about 10 minutes and is intended only to signal to my muscles that they’re still needed. This consists of one max set pushups, one max set generic TRX rows, and some squats, lunges, or kettlebell swings. Sometimes I do these really slowly. I picked up this protocol from Body By Science by Dr. Doug McGuff. Think of this as push, pull, legs, AKA the Big 3. There’s also a goofy but cool concept called Fastercise that advocates isometric and micrometric (my word) exercises to stave off hunger. Comparing DEXA scans between 2018 and 2022 I’ve gained a little muscle, so the JFFs don’t seem to be hurting when combined with my other lifestyle interventions (a moderate protein ketogenic diet and inconsistent weight training). I don’t do any Zone 5 high intensity exercise during a JFF.

Is it really FASTING?

Yes. No. Maybe. Sure. The real question is, does it deliver results? Well, it does for me and it may for you. Yes, everything you consume that adds energy reduces the amount of energy you’re taking from your fat stores. A Jet Fuel Fast may work slightly less well for weight loss than a water fast. Or maybe it will work better because you have more energy. For example, say I ingest 160 calories of MCT powder and 70 calories of ketone salts throughout the day, only when very hungry or needing brain energy. Because I’m feeling so good and comfortable I happily execute a 45 minute bike ride, Big 3 workout, and stay on my feel all day chasing my kids and cleaning house. My BMR, TDEE, and exercise calories burned equal 2050 (per my Oura ring). Compare that to a water fast day when (although I’m told I should feel great) I really just stare at my computer all day while my kids fight, burning 1600 calories. With Jet Fuel Fasting,  I consumed 230 calories of jet fuel ingredients and gained back 450 calories of energy. More importantly, I wasn’t miserable, prioritized connection with my kids, and generally had an easy, fun, and productive day.

But let’s do a little math over the course of an extended Jet Fuel Fast. Say you comfortably sustain a Jet Fuel Fast for 88 hours (Dinner on day 0 through lunch on day 4) and consume a total of 1200 calories over those 3.5 days, plus maybe a 1000 calorie dinner on day 4, taking in 2200 calories in 4 days total. Compare this to a miserable 4 day stint of calorie restriction (say, 1450 calories per day, for a total of 5,800 calories). Well, 5800-2200 is 3600. Goodbye one pound of mostly fat. By the way, your scale weight will be down way more than one pound (maybe up to 5 pounds), but a lot of that will be lost water weight, inflammation, etc. Again, don’t let the snake oil salesmen convince you that all of that weight is fat. It’s not. So say you start at 156 pounds, After a 4x day JFF you weigh in at 151. Hooray! Just know that you will drift back up to 154-155 over the course of the next few days. It’s cool. You can keep doing this one or two times a month. And you can throw in Jet Fuel Time Restricted Feeding (TRF).

(Note that I’m at the upper end of “normal weight” and muscular, so losing a pound is pretty hard for me. If you’re overweight then your math will work out better than mine and you’ll lose more weight, probably because your extra weight burns more calories in a day and also because your body will be more willing to let go of it.)

Other Experiments

Here’s a list of tweaks, diets, and approaches you can try in order to meet your goals. I recommend that, whatever you try, you approach it like a scientist. Change one thing at a time for a specified period of time. Decide ahead of time what you’ll use to measure success.

• Alternate day fasting
• Fat Fasting
• Keto with vegetables
• The Carnivore Diet
• No-carb keto
• Mediterranean
• Paleo
• Eat like a peasant
• One meal a day
• Two meals a day
• Protein sparing modified fasting
• Any IF (18/6, or 20/4, etc.)
• The Warrior Diet
• Lots of HIIT training
• Focus on stress management
• Focus on sleep quality
• Don’t eat before bed
• Always take a walk after meals
• Increase fiber and bulk from vegetables
• Large meals for metabolism
• Higher calorie “feast” days for metabolism
• Dieting one week a month and focusing on maintenance the rest of the month
• No snacking, only meals
• No meals, only grazing
• Focus on nutrient density
• More or different electrolytes
• Apple cider vinegar
• Absurd amounts of water
• One huge salad a day
• Extended fasting (36 hours to 5 days)
• Low fat
• Mono-dieting for short periods (like just potatoes, or just ground beef)
• Boring food
• Lots of Zone 2
• Resistance training
• Sauna
• Prebiotics and/or probiotics
• High protein
• High fat/low protein
• Focus on your life, not your weight