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Confession: I’m something of a nutrition nerd. I find great joy in experimenting with different diets, macronutrient silliness, supplementation—primarily to see what effect is has on physical and cognitive performance. My friends frequently joke about all of the “dirt flavored” food I eat. Sometimes these experiments are successful, sometimes they’re a wash, and sometimes they’re a complete bust. Like that time I ate only tacos for a month.
I began studying ketogenic eating after years of hearing stories from friends—mostly endurance athletes and high-performing entrepreneurs—about their success using it to hit race weight, fuel through incredibly long events, and to boost brain function. A multi-year stint in CrossFit predating my running career had the concept of “fat-adaptation” on my radar, but it was something that most folks I had interacted with simply didn’t understand. I decided to double down and run my own experiment.
After 45 days of eating around 20 grams of carbs and 100 grams of fat per day, I had dropped twenty-five pounds of fat. My runs were getting faster, my brain was on fire, and I had more energy than I had in years. For the first time in my life, I was developing a visible six-pack.
My friends and family were taking notice. Some of them insinuated that I was relapsing, assuming the rapid weight loss and some of the initial side-effects of ketosis were due to drug use. Ironically I was totally clean and sober. Others, however, were curious about what exactly it was that I was doing. My parents eventually reached out, asking for some advice on getting started.
We chatted for a bit on the phone, but talk about nutrition almost always turns towards the esoteric. Having spent nearly a decade studying these things in great detail, it’s sometimes easy to forget that you’re essentially speaking a foreign language to most people. My mom stopped me, “Um, do you think you could write some of this down?”
Eventually I did, and that document circulated for a while. It finally occurred to me that perhaps my quick start might help others who are interested in trying keto out.
I try to remain non-dogmatic about nutrition. While I do have some strong convictions, I believe the proof is in the proverbial pudding. We’re all different genetically and metabolically, our gut biomes are different, and so on—there’s consequently no one-size-fits-all solution. You must experiment and you must measure—at the end of the day, performance and a healthy blood panel are the best indicators of success.
Also, I am not a doctor, and this should not be construed as medical advice. Find a medical practitioner that truly understands nutrition (this is not easy) and consult with her before making any big changes.
Then find a sustainable approach that works for you and run with it.
You have to willing to fully commit for at least thirty days to see this work. Sixty or ninety days would be even better, as the amount of time it takes you to reach a beneficial level of ketosis depends heavily on how carb-adapted you are. For some people, ketosis can happen in just a few days, while others may take weeks or even months.
Plan to not eat out for the first thirty days. It’s just too hard to eat in restaurants while you’re still learning what you can eat, how much carbohydrate your body can tolerate, and so on. If you need to go to an event—a birthday dinner, for example—eat something before you go so you’re not super hungry, and research an appetizer or small plate before you leave. You won’t make anyone uncomfortable and avoid putting yourself in a tempting predicament.
Give Your Liver a Break
Ditto for alcohol. Even healthier, low-carb options like vodka, clear tequila, and very dry wines (champagne and prosecco are the best choice) will raise blood sugar levels, increase triglycerides, impede stem-cell formation, deplete b-vitamins, and spike inflammation. If you do choose to drink, take caution: ketone bodies are made by the liver. This means that your liver gets busy making ketones, and has less time available for metabolism of toxins. You will get drunk faster and you will have a much worse hangover.
Beware the Haters
Plan on having people tell you how dangerous, crazy, and unhealthy this is. These people—possibly including your doctor—likely know little about nutrition, biochemistry, biology, and fitness. It sounds silly, but it gets annoying. Don’t listen to the naysayers, they’ll suddenly become believers when they see the results. Depending how entrenched your doctor is in “conventional wisdom,” you may have to negotiate on this, e.g. “Let’s try it for sixty days and look at the blood work and go from there.”
What Gets Measured Gets Managed
Get blood work done before you start so that you have a baseline. At a minimum you want a full metabolic panel that includes APO(a) and APO(b), cholesterol, triglycerides, H1AC, fasting glucose, ALT/AST, and HS-CRP. You’ll ideally want to run this test every thirty days for the first few months to get a true metabolic picture of what’s happening.
Initially, you’ll need to do ketone testing every day to get a sense of when you’re in ketosis and for what different types of foods do to your ketone levels. At first, urine test strips will suffice, but over time your body adapts and will stop excreting acetoacetate—ketones in the urine. You’ll eventually need to test blood, which detects betahydroxybutyrate (BHB), but at that point you’ll likely have a pretty good, innate sense of where you are. There are also tests for acetoacetone (ketones in the breath), but they are expensive and unreliable at the moment (if your breath starts to smell like nail polish remover, this is why. It will normally go away).
Measure upon waking since you’ll be in a fasted state, and then thirty minutes to an hour after a meals.
Note that if you’re taking a medication like Metformin, you’ll need to watch your blood sugar levels very closely. Once you drop get to >= 1.0 mmol/L of BHB, your blood glucose level will drop substantially, since your body will be running primarily on ketones (fat adapted). Drugs like Metformin lower your blood sugar, so the combination can potentially push you to a dangerously low glucose level (generally speaking, <= 54 mg/dl). In this case, opt for a blood testing meter that does both ketones and glucose.
The ideal range for health benefits is 1.0 – 3.0 mmol/L. You’re technically in ketosis at 0.3 mmol/L, but you won’t see much benefit at that level.
Start off with ~20 grams of carbs per day. This is the level that almost guarantees ketosis at optimal levels. You’re going to have to work hard to keep track of this at first, since you will be surprised at the amount of carbs in some foods. For example, a cup of blueberries contains 21 grams of carbs.
There’s no shortage of food-log mobile apps, and the good ones will allow you to adjust their settings to work well with a low-carb-high-fat (LCHF) macronutrient ratio, and most have a gigantic food database. Plain old Google is also your friend.
Once you’ve spent some time in ketosis, you can slowly increase carbohydrate intake while measuring the effect on your ketone levels to see how sensitive to carbohydrate you are. Generally, 50 grams of carbs is the ceiling, but for some people, it’s significantly lower.
Count Your Chickens
Be careful with proteins. This is not a high-protein diet, it’s a high-fat diet. In excess, protein is converted into glucose and then is stored as fat through a process called gluconeogenesis. You’ll eventually get a sense of how this works with blood testing. Stay close to the standard values of 0.8g/kg for men and 0.6g/kg for women, or even slightly lower. Portion size is the best way to control this, for example four ounces of chicken breast (half a breast) versus eight ounces.
Note that “muscle wasting” (catabolysis) in most medical or exercise contexts is a fallacy. Humans utilize macronutrients for energy in the following order: carbohydrate, fat, protein. Your body will only start catabolizing muscle for energy when body fat percentage is <= 4%. If your body fat gets this low, you’re below the threshold for essential fat and you’re at high risk of death (which will make you incredibly lean but isn’t a healthy long-term option). This generally yields a 5:20:75 (C:P:F) macronutrient ratio. If you have a sense of your basal metabolic rate (BMR, there are online calculators or you can have it tested in an kinesiology lab), then you can easily calculate actual grams.
Reject Calorie Mythology
There is a similar concept with calories—sometimes called the “calorie myth”. It’s not as simple as calories in, calories out. Excess energy is normally stored as fat in the presence of increased insulin in the body, for example with prediabetes or type-2 diabetes. When you are in ketosis, you will by definition be producing less insulin (less sugar means less insulin) so any extra calories you get from the increased fat intake will be used for energy, and are not stored. This can potentially lower your basal metabolic rate, but this doesn’t mean that you’ll start gaining weight.
Intense exercise, particularly during the first week or so, will speed up how fast you reach ketosis. This is because you will be exhausting stored energy in muscles—glycogen—but that energy is not replaced due to a low carb intake. The net result is that your muscles will begin using ketone bodies to supply their energy, and will accelerate the metabolism of stored fat to create these. Go join a couple spin classes or do some high-intensity-interval training.
Buck Childhood Convention
Suspend the commonly held idea of three meals per day, snacking, etc. to “stoke” the metabolism. This is simply not how the human body works. Eat to satiety. Once you’re fully fat adapted, you might only eat one or two meals per day.
Also, don’t worry too much about cholesterol. Your good to bad ratios will change as you fat adapt, and high good cholesterol levels in this metabolic state are generally not dangerous. Not to mention that high-cholesterol does not cause cardiovascular disease, a poor lipid profile does. If you stick to high-quality fats and proteins, this shouldn’t be a problem.
Too Many Mind
Contrary to popular belief, the brain does not require carbohydrate to function and can run perfectly solely on ketones. Most people will notice increased mental acuity and focus while in ketosis.
You’ll probably need to clean out the fridge and pantry. There are just too many opportunities for bad decisions, especially in the first few days. If you have a lot of food, this will be expensive and probably difficult. Don’t stock way back up—you’ll be experimenting for the first few weeks and learning new recipes. You’ll be tweaking menus as you learn more and see how you feel. Plan to hit the grocery a few times per week for the first couple of weeks.
Keto Flu is A-Coming
This is the proverbial elephant-in-the-room. Yes, you’re probably going to feel like shit for the first few days, a phenomenon affectionately known as “keto flu”. It manifests as flu-like symptoms as your body’s electrolyte balance changes. Your body requires less fluid to process ketones than it does carbohydrate—this extra fluid is what causes bloating. Your kidneys will start to dump fluid, and you’ll urinate more as you transition into ketosis. This is temporary, usually only lasting a week or two.
The release of fluid also changes your electrolyte makeup, which is the main keto-flu culprit. I’ve had good luck alleviating symptoms by taking a single Salt Stick—used by endurance athletes during long events—first thing in the morning. If you start feeling bad during the day, take another with a large glass of water. Be careful with the sodium content here if you have medical issues like Meniere’s that require you to limit salt intake.
Also common is dry mouth (heads up, people might think you’re high when they see this—this was legitimately a problem for me). This is one of the ways I can tell when I’m in ketosis. It gets better with time, but it doesn’t go away completely. Hydrate and get some xylitol gum, which is actually good for your teeth and gums (warning: xylitol is HIGHLY toxic to dogs).
Beware Hidden Sugar
Stay away from fruit, with the exception of avocado, which you should be eating in absurd quantities. A small amount of blueberries are okay, but they’ll only serve to prolong sugar cravings. Remember, sugar targets the same dopamine receptors in the brain as many street drugs, and there’s often “withdrawal” associated with carb cessation.
Ditto with cashews, they’re high-carb. Eat macadamia, pecan, brazil nuts (all ~4 grams of carbohydrate per serving, NOT per bag).
You’ll also want to avoid starchy root vegetables, but don’t fret too much about eating veggies. They contain important phytonutrients that you don’t want to miss out on.
Watch out for dips, dressings, and other condiments since they usually contain added sugar.
It’s All Good
Remember, just like any other “diet”, you can eat keto and still eat like complete shit. Eating pork rinds and grass-fed butter twice a day might help you drop pounds and will lower blood sugar (I know, I’ve tried it), but this doesn’t make you healthy.
See y’all on the trails!