I finished my first monthly experiment – Ketogenic diet and fasting.
There’s a lot of things to write about both keto and fasting, so I decided to split results into two parts. Second part will be about the interesting experience with 3 day fast, and here in part one I will start with reviewing ketogenic diet.
Recently there is a lot of excitement (in a positive or negative way) about this diet, and news about the potential health, longevity and performance benefits of (certain) fats even appeared in mainstream media. But is it a new fancy fad, just a tool for specific sets of people (top athletes, epilepsy and cancer patients), or is it relevant for a regular person like me and you as well?
Let’s find out.
Note: this post is very long, so it’s divided into these sections
- Why ketosis
- Protocol/meals (with quick hacks)
- Tricks for food cravings
- Keto flu
- Measuring ketones
- Weight loss
- Exogenous ketones
- For women
- Breath holding
- Final judgement [Spoiler: it’s a definite “Hell Yes!” for me]
While there are some risks and caveats to ketogenic diet, it can be used as medical intervention for issues related to energy production (epilepsy, cancer, Parkinsons, diabetes, Alzheimers, …), or as a tool to enhance performance (both physical and mental), or as a fast mimicking diet to extend lifespan/healthspan. Some use it with good results for weight management.
Positive side effect: it saves time.
Protocol / meals
It takes time to adjust to this diet. This is because you have to make sure that your energy intake from fat is at least 70-80%, and it has to be specific sources. The fact that I don’t really eat meat (I eat fish) and am allergic to avocados doesn’t help.
- Sources of fat: MCT oil, butter, coconut oil, fatty fish and seafood (salmon, tuna, sardines or even cod liver), avocado, fatty meats including bacon, macadamia and other fatty nuts.
For me olive oil seemed to block ketosis for some reason, check what it does for you.
- Make sure your fat comes from a good source, especially fish, meats, butter and nuts.
- Always carry backup food with you to be prepared for lack of fatty food options. My go-to is small bottle of MCT oil, individual 10g packs of butter, macadamia nuts. For flights I add veggies (cucumber, Brussels sprouts, red radish) as well.
- Use some tool to calculate calories, otherwise you will get lost.
I couldn’t find anything I liked, so I created my own simple excel tool with foods that I eat often, typical portion and nutrient content and a few formulas to calculate the ratios. I cleaned it up a bit and shared it here, together with the list of meals I ate during first two weeks for your inspiration.
- Learn to weigh your food with your eyes to make calculations easy. I learned how does the usual portion look like for foods I would eat most often – Brussels sprouts, arugula, kale, … That way I don’t have go weigh each portion.
- Most of the veggies can be eaten in liberal amounts. Careful with carrots, peas, sprouted beans etc. (potatoes don’t count as veggies)
- Each meal should be ketogenic. Even if you drink BP coffee for breakfast and lunch, you can’t have the rest of the carbs in the evening – it will kick you out of ketosis. Balance each meal to have the right ratios.
- The best hack I found: you can have 40-50 grams of blueberries when you drink bulletproof beverage, or you can calculate the same with coconut or heavy cream.
There are some limitations. It is definitely possible to have tasty and healthy ketogenic meal. But over time I started missing some of the flavors because everything tasted kind of fatty. Getting enough fat was a challenge since I can’t eat avocados and I generally don’t eat almost any meat. I had to rely on fish and dairy products (fat cream and sour cream), both of which I normally I try to limit. I’m not too good with dairy, and I used to have elevated mercury levels so I limit fish. I challenged myself to have no-fish-no-dairy days, but if I didn’t want to drink coconut oil it was not that easy. I ended up eating some pork after many many years.
Tricks for food cravings
They may or may not happen, but it’s good to be ready. For me it was not about craving for sweets, I luckily went through that phase some time ago. Most of all I missed fresh flavors – I missed them so much that I bought 4 packs of blueberries and was not able to eat them because I still had to keep the ratios 🙂
Trick is to have some snacks prepared – nuts (with salt to add flavor), very dark chocolate (99% is the best, but most of >80% should be OK. Check carb content, but don’t go for those with malitol etc – they’re not healthy and they’re disgusting anyway), veggies with more intense flavor (small red radish can go a long way). Bulletproof cocoa, matcha or turmeric latte from coconut cream are great too. To perk up your BP coffee try adding matcha, it’s the best! A few pieces of blueberries or raspberries are OK after a fatty food.
I wrote about this before, but it’s good to repeat. Don’t forget about the increased mineral intake.
If your body is not used to use ketones for energy, the sudden drop of glucose will make you feel tired and sleepy, have headaches, maybe even nausea. I thought I’m kinda fat adapted already, but on 3rd day I got such a bad migraine that I thought I would throw up.
Some people write that keto flu can lasts 3-4 days. I got out of it in 20 minutes. What helped? ¼ teaspoon of salt with water.
To avoid keto flu, you should
- Speed up ketosis onset by taking exogenous ketones, C8 MCT, or (recommended by Tim) going for a brisk walk.
- Make sure you eat enough and drink enough
- Keep minerals in mind. At least for a few first days drink water with Himalayan salt in the morning. If you experience muscle cramps, you need more magnesium or potassium. Natural keto-friendly food sources might have enough of these (leafy greens, fish, avocados, nuts, dark chocolate), but I guess first few days it’s better to play it safe and take some supplements if you feel things are not going the right way.
Convenience / Productivity
After you know what to do, ketogenic diet becomes extremely convenient in a life of a busy person. My estimate is that I saved up to 1 hour daily by not having to care so much about the food.
My usual approach used to be bulletproof coffee in the morning, lunch, dinner, maybe some nuts in between). Dr. Dom’s recommendation is slightly different. You eat quite a big (and tasty) breakfast, and then you just sip your bulletproof coffee throughout the day and have dinner in the evening.
That way you don’t waste any time with thinking about or eating lunch and snacks. You don’t feel any crash in energy levels, your mind is pretty clear. If you have a busy day I highly recommend this regimen.
For me it was perfect because that week I had to join some meetings during the lunch time, and I had zero issues with that.
Various people react to the diet differently so you can consider measuring ketone levels to be sure you transitioned to ketosis.
You can measure ketones from
Cost, precision and pain levels should be considered. Blood is the most precise, but also the most expensive and invasive. I picked Ketonix, which analyzes acetone levels in breath. Advantage is that there are no operational costs – you just buy the device and then you can measure as many times as you want. It’s also completely non-invasive. Disadvantage is that it only measures acetone (not BHB), and interpreting the score can be a challenge. If you are in Singapore, I’ll be happy to provide it for a week or two so that you can follow your progress.
The main selling point for working professionals is the supposedly steady flow of energy without highs and lows.
When in ketosis, I could feel major difference. Positive difference.
It was very easy to compare since for third week of experiment I switched back to my usual diet. I must admit this was half because of the experiment and half because I spent it in my home country, Slovakia, and I wanted to enjoy some of my childhood favorites (google “makove sulance” or “bryndza” or “ostiepok. They all may look disgusting, but the taste…!). It was great to enjoy those treats, but there was a downside. Even though I had more hours of sleep than usual, I often felt crappy, sleepy after lunch and tired in the evening. I started experiencing distracting food cravings, my almost perfect poo schedule was disrupted. Originally I was planning to do a lot of writing during that week, but I lost focus.
Getting back to ketosis after this week was tougher than I thought. Not so much because of the physical signs, but more because of my psychological state. I’m not sure how much it was because of the shitty diet I had for a week before that, but I was depressed after a long time. It was triggered by things that I still find objectively unpleasant (I thought my personal notebook is bricked just a few weeks after losing my phone and accidentally deleting some very important data), but normally I would not expect that I will react by opening a bag of dried pears and eat it whole while sitting in the corner of my mother in law’s bedroom.
Yes you will probably lose weight. A) you will burn fat and B) you will feel less hungry.
Losing weight was not part of my plans, I’m quite happy with what it is right now. I was closely tracking my food and counting calories for each nutrient group to make sure I’m really eating ketogenic and I get enough calories. In first week I lost about 1.5 kg (3.3 lb) and since this was not my goal I decided during the 2nd week to try to increase my daily calorie dose to 3000 to counter the weight loss.
That was probably not the best idea, especially not to eat big part of it in the evening. I almost puked and ended up going to bed at 10pm. On one hand that made my Oura ring extremely happy and for the first time it gave me full score for sleep timing. On the other hand sleeping at 10pm while having nausea is not my ideal idea of the evening. Next day I was focusing on eating veggies with just necessary amount of fats, and ended up with total of 1255 calories only. I didn’t get hungry or run out of energy.
Overall after 9 days of ketogenic diet I lost a bit less than 2kg from my original average of 55kg. I didn’t get a chance to check my weight at the end of 3 day fast but I estimate I went down to somewhere around 52 kg. After the week with carbs I was back to 55+ (it was just before my period when I usually do 56+), then after another week of keto I went back down to 53.7 kg. Now after I re-introduced carbs I’m still at around 54.
After the whole cycle (2 weeks keto, 1 week carbs, 1 week keto) I lost roughly 1kg, which is not too bad. I think it’s quite realistic to expect I would be able to adjust loss/gain by adjusting the calorie intake or cycling keto with my normal (relatively low carb) diet, but I would have to explore it further to be sure.
Life brings you situations when you can’t follow the diet. If you need to stay in ketosis even in that situation you can try taking exogenous ketones. There are tons of them on the market now. I used KetoForce because that’s what I had in fridge.
I didn’t really have issues to follow the diet and getting into ketosis, so I ended up only taking it 4 times during that month. I heard a lot about the horrible taste, but I drank it with a bit of water with citric acid and it was OK.
First time I used it as a ketosis insurance on the first morning of my 3 day fast. I was really curious how quickly I will see spike in my Ketonix measurements, but I couldn’t see any difference. I should’ve expected it – Ketonix measures acetone, while KetoForce is beta-hydroxybutyrate.
I had no digestive or other issues, but there is not much long term research when it comes to exogenous ketones. Read a lot and talk to a professional before you do something that might harm you. And never do high carb + ketones.
Overall I think I will not be buying exogenous ketones in the future unless I’ll have some health issues or specific goals. It seems that if I combine the diet, C8 MCT oil (e.g. Brain Octane) and brisk walk, my fat metabolism is switched on.
Studies that I’ve seen on impact of ketogenic diet on performance are done with men. Hunger, satiation and metabolism in general are managed by hormones, and there are known differences between the two sexes.
But there are also many differences on individual level, so general statement “men are different from women” might not mean much. Ketogenic diet is used as epilepsy treatment for both girls and boys. There are even women whom it helped with polycystic ovary syndrome, even though reactions vary. On the other hand there are women who had very irregular period after long-term ketosis, until they increased carbs.
If you are a woman interested in benefits of ketogenic diet, I guess you just have to try how it works for you personally, and be a bit more careful in the process. Check your hormones.
For me personally it worked pretty well except during period. Even when I do my weekly one day fast during the period, I have headache and I am more grumpy and irritable than usual. The same thing happened to me on ketosis (2nd day), and unlike keto flu it could not be solved by salty water. Food cravings were quite intense too, which made me distracted during a busy day at work and I had to use all the Pomodoro magic tricks to keep myself focused.
Lessons learned: I will avoid ketosis at the beginning of my period
I did only one measurement so unfortunately I can’t comment. I will be doing Wim Hof experiment sometimes soon so I can look at it properly.
Final judgement: Hell Yes!
I’m really glad I followed through.
I will not be on this diet full time (there is little disagreement about that being not healthy for most of the people), but switching the body to fat metabolism had very palatable positive results.
I will be following ketogenic diet on and off (e.g. Mondays when I have meeting during lunchtime), and combining it with intermittent fasting, one-day and occasionally even longer fasts.
I love the increased but steady energy, focus, practicality and convenience, and the time saved by not having to think about and gathering food. If you could save 1 productive hour from your day, what would you do with all that time?
Of course I have to highlight: this is n = 1 experiment. Every one of us is different and will react differently. But I definitely recommend to at least give it a good try and see how it works for you. Watch your hormones if you plan to do it long-term, but cycling on and off should be relatively safe for most people.
If you have any questions, comments, or want to add some keto tricks, let me know down in comments.
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