A Complete, No-B.S. Guide to the Keto Diet

Parker Saussy
Feb 12 · 17 min read

In the past year, it seems like the Ketogenic Diet — the “Keto” diet, for short — has had something of a boom in popularity. Every lifestyle personality has started pitching it, every supplement brand line has added an exogenous ketone to their catalogue, and every “life-hack” Instagram entrepreneur has turned to plugging a high-fat/low-carb diet as a means of unlocking some otherwise unrealized potential.

And, as with every meteoric fitness/nutrition trend that works its way into the mainstream, this burst in popularity has come with its own (un)healthy share of misinformation and opportunism. Keto is often being sold to the public as a “fix-all” diet that will address and help to fix every aspect of your holistic health — all of it accompanied by the hyper-consumerist language of social media entrepreneurs.

So what actually is ketogenic dieting? How does it work? Who will it work for? Should you try it? How should you sort fact from hypebeast fiction in the world of keto dieting information? These are all questions that I hope to answer in the coming piece.

What is the Keto Diet?

This seems as good a place to start as any.

The Ketogenic — or “Keto”, for short — diet is a nutritional methodology that focuses on minimizing carbohydrate intake while increasing fat intake, so as to trigger specific reactions in the body. It first emerged (into the etymological understanding of modern Westerners, at least) in the 1920s and 30s as a means of treating epilepsy before anticonvulsant drugs had become commonplace or readily available to the public. Among groups of patients studied at the time, over half saw a 50% reduction in epileptic attacks (and a third saw almost a 90% reduction) while adhering to a ketogenic diet.

Similar conclusions had been drawn about the link between keto and epilepsy as far back as ancient Greece, where physicians found that seizures and epileptic attacks were dramatically reduced when patients incorporated fasting or a primary focus on green vegetables into their nutritional regime. As well, some anthropologists have suggested that certain Inuit tribes may have inadvertently followed a Ketogenic diet by being forced to subsist on mostly fish, small plants, and whale fat, though this claim is less substantiated.

Keto’s popularity has come in waves over the years, spiking in the early 20th century and again in the mid-90s, with the latest surge seemingly coming in the past year.

How does the Keto Diet Work?

To preface this section: I am not a licensed nutritionist, nor did I major in Bio/Organic chemistry, so some of my verbiage here may be off. Bear with me, though — I will aim to be as precise as possible.

For the nutritionally uninitiated, common-knowledge nutritional science dictates that the human body needs 3 main macronutrients to survive: Fats, Carbohydrates, and Proteins, all of which have a corresponding calorie count when metabolized fully in the body (4 kcal/g for Carbs, 9kcal/g for Fats, and 4 kcal/g for Proteins). A “complete diet” for a human will involve some proportion of these 3 macronutrients, or macros — for example, if a bodybuilder is aiming to put on mass and must eat around 3000 calories a day to do so, it will be critical that a high proportion (30–45%, depending on who you ask) of these calories come from protein. This proportion will vary widely depending on one’s fitness regime, daily activity level, body composition, general state of health, and genetic profile (no two humans are alike and there is no universal dietary “catch-all”), but close attention should always be paid to macronutrient split when putting together a complete, holistic meal plan.

Each macronutrient has different functions throughout the body: Carbs serve as energy sources while also helping with digestion, Fats help maintain joint, brain, and organ health, and proteins help build and maintain muscle mass — and, of course, each macronutrient has many more uses throughout the body, but this is just a snapshot.

As such, traditional nutritional wisdom has held that Carbohydrates are — and should rightfully be — the main source of energy in the human diet. While the body is physically able to metabolize all 3 macronutrients into energy (an evolutionary adaptation which has allowed humans to survive even with little access to food), the metabolic process for metabolizing carbohydrates is the most effective & efficient — it is, if I may borrow some technical language, effectively the “default” metabolic setting for the body, with processes for the other 2 macronutrients being often delegated to secondary status. And while nutritional science is a relatively recent addition to the scientific lexicon, this conclusion has still been historically easy to accept, given that the lion’s share of readily-farmable food crops on planet earth have been Carbohydrate-rich: wheat, grain, corn, rice, potatoes, quinoa, most fruits, beetroot, etc.

This is where the Ketogenic diet disagrees. The Keto diet hypothesizes that the process for metabolizing fats for energy — Ketosis, from which the diet gets its name — is an equally effective way for the body to receive all of its energy. The Keto diet also supposes that the reasons that carbohydrates have historically held such prominence in the human diet are more external than anything else; i.e. mainly due to their abundance on Earth and the ease with which they are farmed. As such, the central idea of the Keto diet is to force the body to metabolize fats as the primary source of energy in the same way that it would do for carbohydrates.

This comes back to evolution and adaptation. If we view the human body as a state machine — i.e. a machine with several defined “states” triggered by different external stimuli — the primary state would be one of metabolizing carbohydrates for energy. In this state, the body will use all 3 macronutrients for their various processes, but will rely on carbohydrates as its main source of energy for both muscles and vital organs. As such, if the body in this state does not receive enough carbohydrates, feelings such as drowsiness, dizziness, irritability or lack of focus may occur — the body’s way of telling you that it needs to eat. Additionally, if the body in this state receives too many carbohydrates (i.e. more than it needs to power muscles through their daily physical regimen, a threshold which also depends on a variety of factors), then the remaining nutrients will be stored in the form of body fat, to be metabolized at a later date when carbohydrates are scarce. This state can be likened to the kind of “default” state that I referenced above.

However, what happens when the body doesn’t receive enough carbohydrates for a lengthy-enough period of time? This would be our next state: Ketosis. Ketosis is the process by which fatty acids — either from food or from body fat cells — are broken down in the liver into one of three bodies known as Ketone Bodies, which can then be used as an energy source in various places throughout the body, primarily in the brain. The body will typically enter Ketosis after 3 or more days without Carbohydrates, though this number, again, will vary slightly person-to-person. Ketosis is, thus, essentially an anti-starvation adaptation; it is the human body’s way of ensuring that, by turning to fat stores for energy, the body will still be able to run even after food has become unavailable for an extended period of time.

This is the central idea behind the Keto diet: enter Ketosis by severely limiting Carbohydrate intake, effectively forcing the body to burn fat in order to maintain muscles and vital organs. As such, the Keto diet is highly effective at burning off excess body fat. While the diet has a number of different effects on the body, one thing is certain: The Keto diet is highly effective at burning fat.

What Effects Does the Keto Diet Have?

Aside from the primary effect on body fat content, the Keto diet has a number of effects on other bodily systems as well. It is, after all, an entirely different metabolic process from typical human metabolism, and affects other systems differently.


Most people who follow the Ketogenic diet will notice an acute improvement in their ability to focus on tasks. The same way that Ketosis evolved out of the evolutionary need to maintain energy levels during times of famine, this focus level likely evolved out of the need for humans to be mentally aware during times of food scarcity. This focus level lends itself to whatever your day job might be, and allows you to think less about food outside of eating hours. This is also part of the reason that Keto has attained its reputation within the entrepreneurial/“life-hack” community, and has thus become very prevalent across social media.


Keto dieters will often notice that their stamina does not come in bursts or in peaks and valleys, but rather at a steady, sustained level throughout the day. This has to do with the rate at which ketones are produced in the liver, as well as with the means by which they are processed as energy in the brain. After the 1st day of Ketosis, over 70% of energy used by the brain will be from Ketone Bodies, so this effect will only become more pronounced as Ketosis continues. This is optimal for those who work a long work day and have no need for extraneous energy spikes throughout their day.


Working out while on Keto has its advantages and disadvantages. For one, increasing calorie expenditure will only magnify the fat burning effects of the Keto diet, and can be a great way to augment it. However, those accustomed to heavy lifting or intense weight training will find it harder to do so on the Keto diet; with less energy being stored in the muscles, high-exertion exercise will likely be harder to perform, and the body will be come tired much quicker. If lifting heavy on Keto, dry dropping the weight and lifting until failure — it will likely be more effective.


Every dieting trend likes to talk about the “glow” that it brings, but with Keto I’ve noticed it to be especially pronounced. You may begin to see a warmer hue to your skin while on Keto, and you may find that your skin appears clearer than usual. These effects will be even further pronounced if you also incorporate an intermittent fasting approach — a common dieting approach often practiced in tandem with strict Keto.


Drinking alcohol on Keto is complicated, but can be managed with the right choices. With the goal of minimizing carbohydrates, there are some alcoholic beverages that should be flat-out avoided altogether on Keto: most Beers (darker beers especially), malt beverages, anything with added sugar (i.e. most fruity or soda-based cocktails, as well as gin & tonic), etc. Many beers these days will market themselves as being comparably low-carb (Michelob Ultra is the most common example), but beer in general should be avoided if trying to stay on track.

This makes straight spirits (or spirits mixed with only carbonated water) ideal choices for drinking while on Keto. While even pure spirits do still contain calories (alcohol itself is metabolized as calories when it is broken down), they will rarely contain carbohydrates.

A word of caution, however: Drinking while on Keto can be risky for reasons outside of base carb consumption. Since both Ketosis and the metabolization of alcohol occur in the liver, they must effectively compete for space if both are happening at the same time. As such, drinking while on Keto can have a variety of results: some people will fall out of Ketosis when they drink enough alcohol, due to the process being effectively “pushed out” by alcohol metabolization, while others may stay “buzzed” for much longer than usual due to the liver being too preoccupied with Ketosis to metabolize alcohol. In either case, alcohol will be metabolized slower than usual, and may lead you to feel more intoxicated much quicker than you normally would. The results — you guessed it — depend on the person.

Why has Keto gotten so Popular?

Part of the reason (a big part, in my estimation) that the Keto diet has taken off in the United States of late is as a reaction to the objectively wrong nutritional advice that most of us were taught growing up: that a healthy diet is one high in complex carbs and low in fats of any variety.

We, as a nation, have historically been “afraid” of Fats and overly willing to embrace a high-carbohydrate diet, regardless of whatever form it took. I would imagine that, if you grew up at some point during the early oughts or late 20th-century, you were, at some point or another, shown this nutritional pyramid:

As you can tell, this model suggests that the lion’s share of our calories should come from carb-heavy sources, such as grains and pastas, while traditionally fattier foods should be eaten in much lower quantities.

Even the “2000 Calorie Diet” (a number selected based mostly on individuals in their late 30s & 40s, but still a farcically low number of Calories for even a middlingly active person) referenced on every FDA-mandated Nutrition Facts label recommends that anywhere from 60 to 80% of our daily caloric intake should come from Carbohydrates. Unless your day job entails carrying multiple hundred-pound logs up a mountain or running a half marathon each day, this is an absolutely asinine macronutrient split. Even with heavy physical activity, most Americans do not need nearly this many carbohydrates to fuel their bodies throughout the day — as such, in most people, many of these calories will ultimately be converted to fat. And yet, we still wonder why America has an obesity epidemic.

So how, you may be thinking, does the FDA get away with promoting a dietary standard that is objectively wrong from every angle and has actively contributed to the fattening of our country?

There are multiple answers, none of them particularly good. The first is as American as apple pie: Lobbyists. In regards to food lobbies showing up to the table in Washington, interests representing Corn, Grain, and Sugar (sugar is among the worst of these, though I’ll elaborate more on that later) tend to be among the wealthiest and, thus, strongest — these, you’ll notice are also some of the highest dietary sources of carbohydrates. It is actively in their best interest to keep Americans fearful of fats and willing to embrace carbs in their diets, and as such much of the US Government’s language around food has been extremely carb-friendly.

Even in the “healthy” food industry, take notice of just how many dishes are prepared with rice, pasta, or root vegetables as a “base” — a terminology used specifically to trivialize and divert attention away from the meaningful caloric content of such “bases”. Even with processed sugar and additives removed, carbs are still carbs, and will be metabolized as such, and if the bulk of a dish’s volume is comprised of rice, pasta, or bread, it will still be very carb-heavy regardless of whatever else is in it. And, as with main agricultural interests, it is in the best interest of these industries to keep Americans comfortable with a higher level of carb consumption.

The other is simply historical. Even with the influence of lobbyists a factor, many of these dietary guidelines were written when most Americans worked some manner of semi-active or manual labor job, wherein a higher level of carbohydrate consumption could be more justified (still not to the level that the 2000 calorie diet recommends, but more than in the modern era). Nowadays, most Americans work sedentary or minimally active jobs, and it follows that many fewer carbohydrates will be required, even for those who are highly active outside of their day jobs.

Keto, as I mentioned in the beginning of this section, is ultimately a reaction to all of these ideas. It rejects the implicit carb-friendliness of most traditional dietary plans, and instead opts essentially for the other extreme: cutting carbs out almost entirely and obtaining those lost calories from fat.

The other (and perhaps bigger) reason for Keto’s popularity is its implicit utility as a diet: most people in America would like to have less body fat, and Ketogenic diets are highly effective at burning fat without necessitating a massive amount of physical activity. It needn’t be much more complicated than that.

Is Keto Healthy for Me?

This is another question with multiple answers, though I will do my best to cover them all.

The term “healthy” is a bit subjective, given that every person has different fitness and nutritional goals. However, in this section, we will generalize the term “healthy” to essentially refer to that which provides the body with adequate nutrients to survive and maintain all bodily processes to their full function while minimizing adverse effects.

Generally speaking, with adequate discipline and attention to detail, it is perfectly possible to obtain the full scope of one’s nutrients while on the Keto diet. There is nothing explicitly inherent in carbohydrates which is not also obtainable from other foods that fall under the Keto umbrella, and with the right level of focus, discipline, and planning, a Keto diet can be followed to the letter without missing any vital nutrients. The key phrase here, however, is that note about discipline and attention to detail; properly prepping Ketogenic meals and attaining the right proportions of fat and protein is hard work, and doing so improperly is probably the biggest point of failure for those starting a Keto diet.

There are several other, more specific points of nutritional failure on the keto diet that should be avoided:

  • Not Eating Enough Fat. With Carbs intake limited, calories from fat must make up for the gap in calories. When starting Keto, many people can manage cutting out carbs, but still may be subconsciously hesitant when it comes to eating more fats — given how deeply the fear of fat has been ingrained in the collective conscience, it’s not all that surprising. However, it’s a fear that must be overcome in order to eat Keto effectively.
  • Eating Too Much Protein. Many people who try Keto — myself included, when I first began the diet — make the mistake of making up for the carb-based calorie gap by eating more protein instead of fat. While protein is, of course, not implicitly bad, eating too much protein and too little fat on a Keto diet can lead to the body attempting to metabolize this protein, rather than fat, as energy. While the human body is able to do this, it is a highly inefficient process, and can lead to a large amount of gastroenterological distress. As well, it can be dangerous in extreme cases, as it may lead to the body effectively eating away its own muscle mass for energy.
  • Not Eating Enough Fiber. Dietary fiber is critical for a number of digestive processes, and also helps the body metabolize carbohydrates at a slower rate (and thus helps minimize the chance of them turning to fat). However, fiber is classified as a Carbohydrate, and is often found in its highest concentrations within other carb-heavy foods, so it can be easy for a new Keto dieter to miss out on adequate fiber sources. Good sources which are generally low in other carbs (and thus low in “net carbs”) include green beans, nuts, and broccoli.
  • Eating Too Many Artificial Sugar-like Sweeteners. While artificial sweeteners and sugar substitutes can be a great way to enjoy sweet flavors you love while staying low-carb, they are often not much better than standard table sugar. While many of them are not metabolized in the same way that sugars are, the body’s reaction to them is often similar: when Maltitol, a common sugar alcohol substitute, is ingested, the body responds by raising insulin and blood sugar levels, just as it would with regular table sugar — the same is true of many alternative sweeteners. While this may not lead to more carbs, it will likely lead to more sugar crashes, especially if consumed in abundance. Use caution — a helpful guide I’ve used in the past can be found here.

All of this being said, it is my belief that Keto is a diet which should only be practiced in the short-term. While it is likely very possible to eat a fully nutritious Ketogenic throughout one’s whole life, I have found that it is generally not sustainable in the long term for one reason or another; Keto is very time-consuming (and often expensive, given the number of specialty ingredients required for some recipes) to prep, it may become repetitive, and it is extremely difficult to eat Keto within the bounds of certain cultural cuisines, just to name a few. Moreover, the purpose behind the Ketogenic diet is a deliberate one: to burn off body fat. And while this will likely never stop being a goal for most people, it is very likely to fall out of the spotlight when other nutritional goals enter the picture, especially in older age. Keto, as such, needn’t be a lifelong dietary change, but rather a temporary discipline at one’s disposal when they feel they could drop a few pounds of body fat.

Even with a diet that includes carbohydrates in abundance, I have found that it is perfectly possible to keep excess pounds off with the right approach, frequent and varied exercise, and — you guessed it — an adequate level of planning, focus, and discipline.

How Do I Eat Keto?

Eating Keto is relatively simple as a concept: Shift your macronutrient split such that you are getting most of your calories from fats, and limit carb consumption accordingly. Simple enough, right?

Well, even with the right knowledge and approach, eating a complete Keto diet can still be highly time-consuming and difficult to maintain. And while the growing popularity of Keto means that there are more readily available Keto recipes now than ever before, it can still be a daily challenge to put together a nutritionally and flavorfully fulfilling ketogenic meal plan.

As a starter, it is important to maintain high fat consumption, as well as to diversify the types of fats one is consuming. Some good places to start include:

  • Nuts. Try out Almonds, Peanuts, Macadamia Nuts, Pecans, or Walnuts as a good source of both poly and monounsaturated fats. Steer clear of cashews, however, as they contain quite a few extraneous carbohydrates.
  • Cheese. Full fat cheese is a great choice for Keto, though should be eaten in moderation to avoid any lactose-related issues.
  • Fish. Fish is not only a great source of protein, but is a great source of healthier fatty acids, and should be worked into the Keto protein rotation.

Additionally, Keto has its own “take” on a number of different foods, augmenting them such that they are higher-fat and lower-carb than they might normally be. These include:

  • Cloud Bread. A light, fluffy bread substitute made from eggs, cream cheese, and cream of tartar. Can sub in for regular bread in most sandwiches or bread-based dishes. Also a staple in gluten free diets.
  • Lettuce-Wrapped Sandwiches. Commonplace in most restaurants nowadays, and an equally good option for Keto meal prepping at home.
  • Almond Flour “Bread”. A form of bread made from using almond flour in place of regular all-purpose or wheat flour, typically accompanied with fibrous thickening agents such as psyllium husk poweder. Also frequently combined with baked cheese to add more consistent shape and texture.
  • Cheese Crackers. Crackers made from crispy, baked cheese. Delicious and perfectly Keto, with a number of recipes available online.

In regards to carb consumption, absolutely zero carbs would be a very difficult goal to achieve; most of the foods even on this will have a few implicit carbs that are unavoidable. Instead, most Keto diets recommend around 20g of carbs or fewer per day — a goal that essentially requires avoiding any and all primary carb sources. Some more liberal diets may allow up to 50g per day, though this will likely only work for those individuals who already possess an especially high carb tolerance.

If you’re curious about other low carb & Keto recipes, check out this site here. It is a great resource not only for recipes, but also for lots of general information related to Keto and low carb dieting.

Should I Try Keto?

If you have goals related to fat loss and are considering trying Keto, my suggestion would be a resounding: Yes, absolutely, you should try it. There is a great deal of science backing it up (especially in comparison with most other dieting trends out there) and, when done properly, Keto can be highly effective for fat loss and general health. Moreover, there is generally little risk in trying out a new diet, and if it doesn’t work or if it’s simply not for you, it is relatively easy to switch off of.

For me, Keto was essentially my first vector into the world of nutrition. It was the first diet that forced me to track meals and count macros, and for some time it was the main driving force behind my fitness goals. And while I don’t keep Keto anymore, I feel that it is a perfect inroad for anybody looking to better their nutrition and get more serious about the way that they approach food.

And if you get a chance to try it, I hope you do too.

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