As I approach my first anniversary on a ketogenic diet, I reflect on some of the many lessons I have learned along the way. I hope that my experience will help others with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).
Why the ketogenic diet for ME/CFS?
There are many reasons keto could help people with ME/CFS – it can help lower inflammation, clear away brain fog, rev up metabolism, and provide an alternative fuel source that bypasses some of the many potential problems with energy production found in ME/CFS. Keto also mimics beneficial aspects of fasting, such as autophagy – the breakdown and recycling of old cells. I have seen benefits in some of these areas and wrote more about these topics here.
Ketosis – the burning of ketones instead of glucose for fuel – is woven deeply into our evolutionary history. Having metabolic flexibility to use different fuels (glucose, fatty acids, amino acids) allowed humans to survive during times of scarcity and is reflected in our metabolism today. Ketosis can be achieved by burning fat stores during periods of fasting and/or with carbohydrate restriction.
This past year, I have witnessed tribalism in diet politics. I have sought out people who transcend nutritional dogma and bring a more reasonable and scientific approach to dietary discussions. While some may disagree with a few of my points below, the unique impairments found in ME/CFS might require a little more attention relative to the general population.
There are many ways to approach keto, but some portray it as a license to eat poorly at the expense of good nutrition – it isn’t hard to conjure images of people stuffing their faces with bacon and butter coffee. As someone with a chronic illness, I am more interested in getting the right nutrients to fuel my body and correct some of the common deficits in this disease. I approach keto through this lens.
1 | Getting macros right can take some trial and error
Some experimentation might be needed to find the right macronutrient ratio (ratio of protein, fat, carbs) that works for you. There are many keto macro calculators online to help get started. Most calculators ask for information on gender, height, percent body fat, activity level and whether you want to gain, lose, or maintain weight.
Carbs: Some experimentation might be needed to find the right macronutrient ratio (ratio of protein, fat, carbs) that works for you. There are many keto macro calculators online to help get started. Most calculators ask for information on gender, height, percent body fat, activity level, and whether you want to gain, lose, or maintain weight.
Protein: I find some calculators underestimate the amount of protein needed. There is a notion in the keto world that eating too much protein will kick you out of ketosis due to gluconeogenesis – glucose production from breaking down certain amino acids. Others believe this concern is overstated, but there is likely individual variation, and it is something to keep an eye on.
The literature suggests that people with ME/CFS may have higher protein needs. The depletion of certain amino acids may indicate that protein is being used as fuel to bypass problems in energy metabolism. More protein could also help to preserve muscle mass. You may need to experiment with protein intake at first. Over time I have steadily increased protein consumption while managing to stay in ketosis. A general rule of thumb is to consume 0.5-1 g protein/pound/day (~1-2 g/kg/day). If you hope to lose weight, use your target weight for this calculation as a starting point.
Depending on your weight goals (lose, maintain, gain), you may need to dial-up or down fat content. Over time, I have lowered my fat intake by about 20 g/day and swapped in more protein. It is important to remember that fat does not make you fat, especially when it is your main fuel source. This can be hard to get past if you come from the low-fat era.
Fat: Keto calculators might over- or underestimate the calories needed in a day. I am a bit underweight and lost a few pounds when I started keto and found that I needed about 200 calories/day more than the macro calculators indicated, though this seems to be changing as I approach menopause. Some may welcome weight loss – it is a well-known benefit of the keto diet. You can also use it to stabilize or gain weight, as I have. You will know when you have hit your caloric sweet spot if you are meeting your weight goal.
2 | Don’t sacrifice micronutrients in pursuit of perfect macronutrient ratios
When I first started a keto diet, my focus was entirely on macros. I shudder to think back to those early days when I tried to minimize vegetables that had too many carbs and protein. My typical breakfast included eggs and bacon with a side of sautéed kale and a few cherry tomatoes. I skimped on avocados, nuts, coconut milk, and spinach because they had too many carbs and/or protein. For dinner, I often limited protein to no more than 3 oz in hopes of avoiding gluconeogenesis. I usually needed more fat at the end of the day to make up for shortages. I leaned heavily on aptly named “fat bombs” – typically a mixture of fats (coconut oil, coconut butter, butter, whipping cream) and a keto-friendly sweetener.
My diet vastly improved when I found Marty Kendall – a nutritional thought leader and engineer who inspires people to transcend dietary labels and focus on pursuing nutrient-dense foods. His Optimizing Nutrition site offers a nutritional Rosetta stone that places micronutrients – vitamins and minerals – front and center. I highly recommend joining his Facebook group – “Healthy Low Carb and Keto Recipes” – but don’t expect to find the usual keto crowd. Instead of recipes for fat bombs, you will find simple meals bursting with color and nutrients. As many of Marty’s followers like to say, focus on micronutrient density, and the rest will follow.
Many nutritional apps are on the market, but many of Kendall’s followers use Cronometer, a free app. Cronometer takes some getting used to at first, but it tracks micronutrients better than most keto apps. The micronutrient levels are set to the RDA, which is basically the minimum amount you need to avoid diseases caused by nutrient deficiencies. Hardly a high bar, but these values can be customized. Most people struggle to meet even these lower levels, and those who follow the Standard American Diet are probably chronically deficient in certain vitamins and minerals.
My advice to those first starting out is to log all food consumed in Cronometer to see which vitamins and minerals are chronically low in your diet and seek foods that can help to fill these gaps. If food-tracking seems like too much of a hassle, I suggest trying it for a few weeks or so until you get the hang of eating a more nutrient-dense diet. To learn more about micronutrients and their various roles in the body, start here.
Nutrient absorption may be a problem for some people with ME/CFS. Therefore, it is best not to assume that nutrient intake correlates well with nutrient uptake. Certain vitamins and minerals can take a hit in this disease, including several B vitamins (especially thiamine, folate, and B12), selenium, vitamins E and C, essential fatty acids, co-enzyme Q10, L-carnitine, and more, though specific deficiencies are likely to vary from person to person given how heterogenous this disease is. You may need more than the RDA suggests, especially if absorption is a problem. Kendall provides an in-depth look at optimal nutrient intake beyond the RDA here. A deeper dive into micronutrient deficiencies and mitochondrial dysfunction by Chandler Marrs, Ph.D. can be found here.
See Table 1 at the end of this blog for a list of some of the top foods for each type of vitamin and mineral.
3 | Have a good plan for replacing electrolytes before you start keto
Having adequate electrolytes and hydration is essential when you start keto. Electrolytes take a hit due to a drop in insulin, which causes kidneys to excrete sodium and other electrolytes and water. This is not a problem per se, but it requires some attention. More hydration than usual also is important to address hypovolemia (low blood volume), a common component of ME/CFS, which can exacerbate co-morbid conditions such as postural tachycardia syndrome (POTS) and neurally-mediated hypotension (NMH).
I wrote about some of the road bumps I hit when I first started keto and learned that I was not taking enough magnesium and suffered from abdominal and leg cramps. Also, I have started supplementing with potassium citrate in hopes of resolving some muscle twitching in my calves.
Marty Kendall has developed an excellent home-made electrolyte mix low in carbs (many commercial electrolyte mixes have sugar, dyes, and horrible tasting artificial flavors). Mix all ingredients and store in an airtight container. Add to water or sprinkle on food as a salt substitute. Glycine is especially important for people with co-morbid connective tissue disorders such as Ehlers Danlos Syndrome, and creatine helps with cognition and strength.
|Potassium citrate powder||19 g|
|Magnesium bisglycinate powder||6 g|
|Sea salt||11 g|
4 | Stock your pantry with a few key items and gadgets
I try to keep things fairly simple in the kitchen. I eat two times a day, with breakfast being an omelet loaded with veggies and salmon or sardines and dinner being a salad and some sort of protein (chicken, salmon, shellfish, pork, etc.) and nuts. I enjoy a few simple homemade salad dressings (beware of hidden sugar in store-bought dressings), helping me reach my fat macro target. I no longer eat fat bombs and get all of the fat I need in the foods I eat (meats, sautéing with olive oil, salad dressings, nuts, and cheese).
The keto diet does not need any special ingredients or kitchen equipment, but I have found a few items to be very handy:
Pantry: Everyone’s pantry will differ depending on individual likes and needs. I keep the following dry goods stocked in my pantry at all times: finely-ground almond flour, Swerve confectioners sugar, nutritional yeast, hulled hemp seeds, macadamia, and other types of nuts, chia seeds, cacao, and cans of sardines. I am a huge fan of Lily’s chocolate chips (made with stevia and erythritol). People differ in their preference for keto sweeteners – I like erythritol and am trying allulose in a cookie recipe I am experimenting with (stay tuned!). Others prefer stevia and/or monk fruit sweetener. I keep baked goods to a minimum, as they take me away from more nutrient-dense foods. However, I do enjoy nutrient-dense muffins and cakes made with almond flour using this base recipe.
My weekly shopping list includes a large bin of spinach (but oxalates are problematic for some), romaine/cos lettuce (unless on recall in the US!), arugula/rocket, asparagus, broccoli, mushrooms, avocados, eggs, cream, almond milk, cheeses, wild-caught salmon, sardines, raspberries, yellow peppers, zucchini, various meats, and chicken livers. Each person’s list will differ slightly, depending on nutritional needs and food sensitivities.
Kitchen gadgets: I find a kitchen scale indispensable for logging my food in Cronometer, which helps me get the right nutrients each day. I use a mini-food processor (thanks to my dear friend who just gifted me one!), a large food processor, and an immersion blender regularly. Others rely heavily on an air fryer and Instant Pot-type pressure cooker – I use these less frequently because I eat very simply most of the time (salads w/animal protein and omelets).
5 | Don’t chase after high ketone levels
Many people consider it a failure if their blood ketone levels are not above 1 mmol/L. Some will increase fat consumption to help foster ketosis and/or continue to cut carbs to virtually nothing, approaching more of a carnivore-type diet. Everyone differs in their metabolic makeup – more reasonable minds recognize this and consider 0.5 mmol/L to reflect a state of ketosis.
That said, it does help to monitor ketones and blood glucose when first starting. Many people use urine strips, which are cheap and handy at first. Still, they only measure one type of ketone – acetoacetate – which levels off after the first few weeks, giving many the impression that they are no longer in ketosis. Instead, as the body becomes more adapted to using fat as fuel, it produces a different type of ketone – beta-hydroxybutyrate (BHB) – which can only be measured in blood. Keto Mojo makes a popular dual blood ketone/glucose monitor for those interested in tracking ketones and glucose over the long term. Alternatively, ketone breath meters measure acetone, a less abundant ketone body.
I use my Keto Mojo ketone/glucometer very rarely now but will pull it out on occasion to ensure that my BHB levels are within my desired range. More recently, I have been using it to test the limits of how many carbs I can consume while still staying in ketosis – I have not found that limit yet but have not pushed past 75 g net carbs/day. I no longer obsess about counting carbs and find I consume between 15-30 g/day without thinking about it too much.
You can also use a ketone meter to test the limits of protein consumption and gluconeogenesis by looking to see if ketones drop with increased protein intake.
Monitoring ketones is not necessary on keto and could easily be skipped.
6 | If keto is too difficult, try periods of intermittent fasting
Tackling a whole new eating way may be challenging for those on the moderate-to-severe end of ME/CFS. Also, some people seem to do better with more carbs than keto allows. An alternative approach for getting some of the benefits of keto would be to eat a diet low in net carbs (~ 100 g/day) based on whole (vs. processed foods) and include periods of time-restricted feeding (TRF) or intermittent fasting (IF). TRF eating is restricted to a window each day.
My ME/CFS physician is a proponent of TRF and IF because of its ability to activate cellular mechanisms that help with immune function and reduce inflammation. She offers this practical advice: start with a 12-hr fasting window and slowly increase the fasting window every couple of weeks. I am lean and was concerned that TRF would worsen my situation. I have slowly worked up to a 16:8 fasting/feeding period with two meals a day at 11:00 am and 7:00 pm. My ME/CFS specialist suggested that I could try eating one meal a day (OMAD) on occasion once I can do this comfortably. I never hesitate to eat earlier in my fasting window if I have a hard time or feel hungry. I would like to try longer fasts but am not there yet.
There are many perspectives on approaching the fasting window – some argue it is OK to have broth and heavy cream and/or butter in coffee. These items have protein, carbs, and fats, so technically, it is not fasting. I started by allowing cream in my coffee during the final hours of my fasting window but now try to limit it to black coffee or peppermint tea (as an aside – coffee is a surprisingly decent source of potassium, a nutrient in short supply in the keto diet). Either approach seems to have a lot of support among prominent physicians, such as Jason Fung, MD, and Peter Attia, MD, who use fasting in their medical practices.
Be aware that cortisol and adrenaline (epinephrine) can rise while in a fasted state. This can make sleep more difficult and worsen POTS. In a previous piece, I wrote about the possibility of increased activity in the sympathetic nervous system in response to keto. For those who geek out on heart rate monitoring, this translates to consistently lower RMSSD – a measure of heart rate variability – and for me is reflected in a slightly elevated resting heart rate relative to my pre-keto days. Such trade-offs need to be weighed over the long term.
7 | Consider cycling some higher carb days every so often
Some nutrition experts argue it makes sense to cycle some higher-carb days on occasion, aiming for ~75-100 g carbs/day. The rationale is that both fed- and fasted-states offer different types of health benefits. The fed state’s physiology offers protective benefits that are energy-intensive, including antioxidant protection (glutathione), glycation defense, and promotion of various cellular repair processes. Being in a fed state also helps promote anabolic processes – the building of vital macromolecules and tissues. Insulin plays an important role in these processes but is in shorter supply while in ketosis. The interesting thing about keto is that it has elements of both the fed state (calories, adequate amino acids, and ATP) and the fasting state (lower insulin).
There is so much confusion out there about this topic, and I don’t want to add to it except to say that everyone is different, and population averages presented in research might not apply to you. There are many documented endocrine (cortisol, thyroid, sex hormones) aberrations found in ME/CFS, and it is unknown how the ketogenic diet will affect you. Cycling higher carb days could ensure the benefits of being in both the fed and fasted states, prevent possible endocrine problems, and balance catabolic and anabolic activities. It could also help with sticking to the diet if a few (healthy!) carbs can be enjoyed occasionally.
8 | Get some baseline blood work done before starting
I recommend that everyone get the following panels drawn while fasted before starting keto: complete blood count (CBC), complete metabolic panel (CMP), thyroid panel, and a lipid (aka cholesterol) panel. A fasting CMP provides a blood glucose value – this could be an important marker to watch, especially if you are diabetic or pre-diabetic; keto can help normalize these values. Knowing your baseline white blood cell count is also handy – some say it drops while on keto. A baseline thyroid panel could help with monitoring your thyroid response.
If you have not had a fasting lipid panel done for a while (or ever), I highly recommend getting one done before you start keto as many of the markers on that test can be influenced, for better or worse, by increased fat intake. While keto is known to increase HDL cholesterol and lower triglycerides (good things), it can spike LDL cholesterol in a small subset of people (~20%). Regardless of your views on LDL cholesterol, it is good to know how your lipids respond to the diet.
9 | Don’t forget the fiber!
Keto is notorious for causing constipation. This occurs because the kidneys excrete more water (and electrolytes) due to the drop in insulin. I sometimes struggle with this and find that a teaspoon of psyllium husk in a tall glass of water helps. I also make a simple chia seed pudding – 1-2 tablespoons soaked in 1-2 cups of unsweetened almond milk with a little vanilla – is a pleasant way to get in some fiber and heaps of omega-3 fatty acids.
9 | Don’t be discouraged by keto flu
I experienced some health benefits within one week of starting keto but I also experienced a lot of nausea – sometimes referred to as “keto flu.” I relied heavily on Zofran (ondansetron), a prescription drug, to pull me through. Ginger tea is also helpful. I wonder how much of this could have been avoided had I taken the warnings to up my electrolytes and hydration when I first started keto. A good overview of the various electrolytes and how to get them in food can be found here. The good news is that keto flu passes, and there are ways of moving through it more quickly than I did.
10 | Beware of mast cell reactions
I recognize that I am somewhat fortunate to eat a diversity of foods without reacting to them. Many of my friends with ME/CFS suffer from mast cell activation syndrome and find that they can tolerate only a very restrictive list of foods. If keto requires further restrictions, it might not be the best diet for some. However, keto is a versatile diet, and there are many ways to approach it. When introducing new foods, pay attention to how they are affecting you.
Keto is not one diet but many and can be done dairy-free, vegan, mostly meat, etc. – there are infinite combinations to try. I am working my way toward “nutrient-dense dairy-free keto” in hopes of bringing down my cholesterol. If you believe the benefits of keto are worth pursuing, I urge you to think carefully about changes in your diet that might affect mast cell problems and/or food allergies.
For those wishing to pursue fully plant-based or carnivore-based keto diets, I highly recommend this piece by Marty Kendall using a data-driven approach that explores common deficiencies in various diets and how to correct for them.
In conclusion …
A ketogenic diet can help with many symptoms of ME/CFS, including brain fog and inflammation. But keto can also exacerbate certain health issues. Hence, it is best to keep an eye on your lipids, hormones, mast cell reactivity, and increased activity in the autonomic nervous system’s sympathetic branch. Many of these aspects can be mitigated, so the benefits outweigh these downsides.
For those interested in the benefits of keto/fasting but wanting to eat a higher-carb diet, I recommend Rhonda Patrick, Ph.D. and her Found My Fitness site and podcast.
For more information about fasting approaches, I recommend Jason Fung, MD.
For more information on ketogenic diets, I recommend some of the resources on the Diet Doctor site.
Table 1. A quick guide to nutrient-dense foods for vitamins and minerals. The foods listed are those that are ranked as being at or near the top for each category but there are many other foods not listed that contribute to daily nutritional targets. Grains and legumes are excellent for many minerals but are omitted here because they are not very keto-friendly due to a high carb content. Most of the information in this table comes from Chris Masterjohn’s free Vitamins and Minerals 101 course, which will soon be in book form. This is by no means meant to be a complete list but rather a sample of some of the top foods for each category. With a combination of different meats, organs, fish, shellfish, eggs, nuts, seeds, vegetables, and low-carb fruits (e.g., peppers, tomatoes, zucchini, raspberries, etc.) you will easily hit most micronutrients.
|Vitamins/Minerals||Some top keto-friendly sources|
|A||Liver, whole eggs, full-fat dairy, red/yellow/orange/green veggies|
|B1 (Thiamine)||Nutritional yeast, pork, chicken, beef, nuts (macadamia nuts especially), seeds (sunflower), hemp seeds|
|B2 (Riboflavin)||Organ meats, almonds, asparagus, red meat, cheese, eggs, salmon, mushrooms, seaweed, sesame|
|B3 (Niacin)||Tuna, salmon, anchovies, liver, nutritional yeast, protein in general, hemp seeds, chia seeds, sunflower seeds, dark roast caffeinated coffee|
|B5 (Pantothenic acid)||Nutritional yeast, organ meats, sunflower seeds, eggs, mushrooms, salmon, peanuts, avocado|
|B6 (Pyridoxine)||Nutritional yeast, liver, chicken, turkey, pork, eggs, salmon, sunflower seeds|
|B7 (Biotin)||Egg yolks, liver, nuts, sunflower seeds, walnuts, peanuts|
|B9 (Folate)||Liver and dark, leafy greens, broccoli, asparagus, leeks|
|B12 (Cobalamin)||Animal products – meat, poultry (but not eggs), fish, clams, oysters, plus shiitake mushrooms|
|C||Acerola cherry, coriander/cilantro, green chili peppers, sweet yellow or green peppers, kale, broccoli|
|D||Cod liver oil, egg yolks, some mushrooms, some fish|
|E||Fatty fish, nuts, and seeds|
|K||Hard cheese, dark chicken meat, egg yolks, chicken beef liver, butter and ghee, dark leafy vegetables|
|Choline||Egg yolks, liver, peanuts|
|Calcium||Cruciferous vegetables (broccoli, kale, bok choy), dairy, canned fish|
|Copper||Oysters, shiitake, cacao powder, sesame seeds, beef liver, spirulina|
|Iron||Organ meats, shellfish, some seeds and nuts|
|Iodine||Fish, seafood, seaweed|
|Magnesium||Hemp, seeds (pumpkin, peanuts, chia, flax, sesame), nuts, coffee|
|Manganese||Mussels, nuts, seeds|
|Phosphorus||Easy to get in dairy, eggs, meat, veggies, seeds, nuts, etc.|
|Potassium||Dark leafy greens, avocados, beets, coffee|
|Selenium||Organ meats, Brasil nuts|
|Zinc||Oysters, calf liver, cacao, dark chocolate, beef, lamb, cheese|
|Omega 3||Salmon, chia, flax seeds|
|Omega 6||Seeds, nuts|