The Keto Diet: What You Need to Know

Nutrition and Diet

The Keto Diet: Originally published November 2017. Updated September 19, 2018.

Well, its been almost a year since my original post about the Ketogenic diet, and what an interesting year it has been for this particular trend!

I chose to re-visit this post and update it because there has been a surplus of research and development into whether or not the Keto diet is all it’s cracked up to be. There have been some new books written, documentaries published, and some prominent characters on the diet scene passionately promoting this way of eating for anyone looking to improve their health.

In The Spotlight

So, Keto has definitely got everyone’s attention over the past year, and no one can deny that many people who give the diet a try see results. But why? How? What is it about the Ketogenic diet that seems to be the solution to so many people’s health concerns?

The cold, hard, honest truth? Calorie reduction.

I know! It’s hard to believe when you look at the types of foods the keto diet includes. Bacon, butter, cream, red meat, coconut oil, cheese, avocado, and all of the other tasty, indulgent, satisfying things that are absolutely forbidden on most other diets. It’s easy as a Dietitian to see why keto holds so much appeal for people who have tried every other diet in the book, because it includes the least “diet-y” seeming foods most of us can think of.

So, what exactly is the Keto Diet all about?

The Keto Diet is a very low carbohydrate diet, similar in some ways to the Atkins diet that was popular years ago. Followers of this diet are expected to consume around 20 grams of total carbohydrates per day (up to 50 grams depending on who you talk to), with the remaining calories coming from fat and proteins. Exactly what proportion of fat vs protein remains debated.

Many of today’s keto followers differ from the Atkins folks because they aim for a much higher fat content, as excess amounts of protein in the diet are glycogenic…meaning your body can create sugar from them.

To Put It All Into Perspective

One serving of fruit provides about 15 grams of carbohydrates. So if you are going to give the Keto Diet a try, that means no fruit, no milk, no yogurt, and no grains. All sugars and starches are a no-go.

Side Note – any diet that promotes bacon as a healthy food immediately makes me skeptical, but that’s just me. Again, some folks choose to go more “whole-foods keto” and limit processed meats like bacon, while others eat it daily. To each their own!

How did the Keto Diet get it’s name?

Well, when our bodies are depleted of carbohydrate stores (there’s no gas left in the tank), rather than dropping dead we’ve managed to adapt to using backup fuel stores. For us, that is our body fat. We use fat as a primary energy source during rest, with carbohydrate going to fuel the brains cells. In that resting state, each molecule of fat that is broken down requires a carbohydrate molecule to complete the breakdown.

You see, the brain runs on sugar (glucose). 24/7 The brain is demanding a constant supply of glucose to keep it functioning optimally. You know when you’re really really hungry and you feel like you can’t focus? It’s because your brain isn’t getting the sugar it needs. That makes some of us (guilty) a little cranky at times…hence the term ‘hangry’.

So, when there’s just no sugar left what’s a brain to do?

Find another power source. The brain can’t turn to fat as a whole substance for energy, but it can use something called ‘ketone bodies’. Ketone bodies are by-products of fat breakdown. They can be used for a backup energy source for the brain in a low-carb environment.

From a weight-loss perspective this sounds kinda great right? Just eat no carbohydrates, and lose fat, FAST! And at first, many folks do. Like many other diet trends that have come and gone over the years, people tend to lose a significant amount of weight up front, but that weight loss drops off and stalls after a few months. This predicament occurs regardless of the specific diet a person follows.

The exact reason is likely a combination of things. The body’s metabolism adjusts after a period of time to the lower calorie consumption, or it’s that like most diets, keto can be hard to stick with forever, through holidays, birthdays, vacations, etc. We tend to start including more indulgences here and there than we did when we were first on a diet and feeling super motivated.

But, what does the research have to say?

Can the keto diet really cure diabetes?

No. There is no known cure for any type of diabetes. A low carbohydrate diet however, can be effectively used to better MANAGE diabetes. A person may even be able to reduce or completely stop some diabetes medications if they follow this pattern of eating. Makes sense, right? If we put less sugar into the body, our blood sugars will likely be lower. But, unfortunately while blood sugars may be controlled while eating a low-carb diet, if a person were to drink, say a 2-litre of pop in a single sitting, a high blood sugar would most certainly be a result. So, a lower-carbohydrate style of eating would need to be followed indefinitely to see the continued benefit.

Does the keto diet really cure things like cancer or seizure disorders?

It’s true, there are a few medical scenarios where the Ketogenic Diet has shown some promise. It’s been used for children suffering from certain types of childhood epilepsy for quite a few years. More recently there was a study using mice that showed a slowing in brain tumor growth by feeding the mice a ketogenic diet. Does this mean a Keto Diet protects us against cancer? Unfortunately, no. Animal studies do not tell us how something will work in humans. We are not mice.

Additionally, cancer prevention and cancer treatment are two very different things. Does it mean that a Ketogenic Diet is good for our brains, because it helped these children with epilepsy? Again, no. These children have a very complicated, unique medical condition. Their brains are not working the way ours do, so a diet therapy for them will not have the same effect on us. People who use these examples to promote a ketogenic diet are extrapolating evidence and are likely they’re trying to sell you something.

Is the keto diet easier to follow than other diets because high fat foods are more filling and satisfying?

At this point, no research has shown any benefit in terms of diet adherence with keto vs other calorie-reduced ways of eating (such as a low-fat diet). When you compare both of these diets head to head, drop out rates from nutrition studies are similar, and weight loss outcomes are also similar. In my opinion, this all comes down to personal food preferences and individual dietary beliefs.

Let me explain…

Fibre, fat, and protein are all known to be “filling” substances in our diets. This means when we eat them we feel full, and are less likely to over-eat (vs eating a plate of refined carbs or drinking soda for example). The thing is however, that fat provides us with more than twice the calories per gram than protein does, and fibre really contributes no calories at all to our diets (but, if we count the carbohydrates they usually come packaged with in foods like whole grains or fruits, it’s the same story.) Carbohydrates and proteins both contain 4 calories per gram, while fat contains 9 calories per gram.

So, perhaps it’s true that fat is MORE satisfying than the other two nutrients, meaning you need to eat less of it by weight to feel satisfied and full. BUT, if that smaller volume of food is giving you more than double the calories, it may still be possible to overeat if you aren’t paying attention to portions. Which may be a reason why not everyone who goes on a keto diet actually manages to lose any weight…it all comes down to the total calories. You personally however, may choose a low carb high fat way of eating because you feel it suits your personal preferences and makes you feel like you aren’t dieting.

The Debate Continues

The other highly debated aspect of the keto diet is whether or not eating large amounts of saturated fat truly increase a person’s risk of heart disease. But, like most things in nutrition science the answer to that question is very complex, because whether or not a person develops heart disease is more than just the food they put in their mouths. Genetics, activity level, smoking, and stress, are all additional known factors when it comes to heart disease, as well as saturated fat intake and blood cholesterol levels. So, yes eating large amounts of saturated fat will very likely raise your cholesterol levels, but whether or not that will CAUSE you to have a heart attack is not quite as cut and dry.

Do I have to be in ketosis to see the benefits of a keto diet?

I mean, by definition yes, but according to the research the benefits of a keto diet come strictly from reducing calories, not from any metabolic or magical process that occurs when we enter a state of nutritional ketosis.

Let me be super clear about this:


I am also not a fan of promoting nutritional ketosis for a few other reasons….

Our bodies do not only use fat for energy when we restrict carbs.

The human body absolutely must maintain a specific amount of glucose (sugar) in the blood at all times. Period. If blood glucose levels drop too low, we begin to feel weak, shaky, and unable to concentrate. If levels drop even further we can lose consciousness, suffer brain damage, and die.

But, that isn’t happening to everyone who goes low carb, so what gives?

The human body is really resourceful, and over the course of our existence on this planet has adapted to just about any nutrition situation. The liver is actually able to create new sugar molecules in order to keep us alive in a low-carb environment, in a process called gluconeogenesis. Isn’t that amazing? But where does the liver get the building blocks that it needs? Muscle tissue. Muscle is a high-maintenance tissue, which means it eats up a lot of energy on a daily basis to keep it functioning. In times of ‘starvation’ (which is exactly the environment the Keto Diet creates in the body), the body will sacrifice muscle tissue to maintain blood glucose levels and reduce calorie needs before it readily parts with fat.

Think Of It This Way

If you suddenly had your income cut down by 50%, what would you cut from your budget first? Probably not essential things like water or electricity. It’s more likely that the first things to go would be the things that aren’t necessary for basic survival. Our bodies work the same way. In a state of starvation, muscle is depleted to decrease the drain on our bodies fuel stores. Your body doesn’t know you’re just on a short term diet, it’s getting ready for a famine. (to read more about the cycle of dieting and it’s negative effects on our bodies, click here)

As a Dietitian and Personal Trainer the last thing I want my clients doing is sacrificing their muscle mass.

Reaching a true state of Ketosis is not necessarily quick or easy

How does a person know they’re in ketosis? That they’ve restricted their carbohydrate intake adequately or for enough time? (depending on the amount of gylcogen stores in the body going into a Keto Diet, it could take several days to actually use them all up. Even longer if you’re inactive). The most dedicated Keto-ers will test their pee using dipsticks to measure the amount of ketone bodies excreted in their urine.

Honestly, I have people who tell me they don’t have time to meal plan or eat breakfast, never mind remember to test their pee everyday. Eating even a small amount of carbs (like in a weekly cheat meat), your body will quickly change gears to use those carbohydrate stores for energy rather than breaking down fat. So if you’re going keto you need to commit. As soon as you start eating carbs again, you’re no longer in a state of ketosis and it’s back to square one.

So, what’s a person to do?

My perspective is that if you’re going to change the way you eat, it has to be for longer than a few weeks or months. If you can’t maintain the changes forever, then why even bother in the first place? That being said, if reducing calories in your diet by cutting back on your portions of grains and starches, and filling up instead on lots of vegetables, proteins, and higher fat foods makes you HAPPY, then don’t let anyone stand in your way! But, please understand that this way of eating is not what everyone wants to do or should do, and be respectful of those individual choices. But I would suggest avoiding getting into ketosis, as there is no real benefit to be had there. Lower carb, higher fat eating with a total calorie reduction (and plenty of vegetables) is good enough!

Anecdotal Evidence?

Many testimonials I see from people swearing the Keto Diet was their saving grace makes me wonder; What was their diet like before? Would simply cutting back on processed foods, cooking more from simple ingredients, and not eating such large portions have done the trick too? Why do we feel the need to take things to such an extreme? We could fill up our plates with vegetables and have a smaller portion of grains, but instead we have this black and white, all-or-nothing approach to our eating. We need to find balance in our diets, and get ourselves out of the mindset that something needs to be extreme in order to work.

What about Ketone Body supplements?

Remember what I said before about people trying to sell you things? There is now a product you can buy (through network marketing no doubt) that contains exogenous ketone bodies that you take as a drink mix. These supplements are meant to push you into a state of ketosis in a short period of time, without needing such a restrictive ketogenic diet. Except, for best results they also recommend following a ketogenic diet.

So, you’re spending a few hundred dollars per month on a product that you can’t really prove if it works or not, because the diet you follow would get you to ketosis anyway. And, we really have no scientific evidence to tell us what happens when we eat a ketone body supplement without following a low-carb diet. How do we make sure those ketone bodies are what we use for energy, and not the carbohydrates we’re eating? To date, there has only been one human trial completed on these products looking at their ability to enhance sports performance and they were a massive flop. So don’t waste your money on this BS.

My Advice?

If you think your diet needs some work, contact a dietitian. Start by changing some small things about the way you eat, like less takeout and more cooking and see where that gets you. Chances are, you won’t need to go to such extreme measures such as the Keto Diet to see a benefit in your health.

For more of my articles on breaking the cycle of dieting, click the links below!

Why I don’t have a weekly Cheat Meal (and neither should you!)

Why Weight Loss Should Actually Be Your Lowest Priority When Starting Your “Weight Loss Journey”

The Most Important Thing You Can Do For Your Health (that no one talks about)

5 Reasons Why You Shouldn’t Take Nutrition Advice From Just Anyone

12 thoughts on “The Keto Diet: What You Need to Know

  1. The Atkins diet does work (have tried it), but only for as long as you use the diet. Once you begin adding carbs back into your diet you will slow down the weight loss and many people, when they go back to eating ‘regularly’ find they put the weight back on. Plus, the first 2 weeks w/no carbs is killer, I had HORRIBLE headaches, I was grouchy and wanted to sleep all the time. My blood sugar was way too low to keep eating like that. I went into phase 2 of the diet rather quickly b/c of that.

    1. Thanks for the comment! Absolutely this diet does not work for everyone (most people really). We know that different approaches work well for different people and while I’d rather see a client eat a wider variety of foods and include carbohydrates in their diet, some people do really like this way of eating, and that’s totally fine for them.

  2. As a fellow dietitian colleague who has been researching Keto for many chronic health conditions, I have to say Stephanie you need to go back and do more research into nutritional ketosis. Ketogenic diets are showing health benefits for numerous conditions, especially those that are linked to hyperinsulinemia. For anyone interested in implementing a Keto Diet, find a dietitian who is knowledgeable and supportive because the diet needs to be well-formulated and may not be appropriate for everyone. It’s time dietitians get their heads out of the sand on this topic! Keto diets are a powerful metabolic nutritional therapy, not a fad weight loss diet.

    1. Angela, as a fellow healthcare provider I expect you understand the importance of remaining evidence based in practice. That being said I assume you are able to provide references to refute the claims I’ve made that you feel are false. I look forward to receiving your list of studies and randomized trials to support the claims you’ve made in your comment. You have my email address.

  3. Yes, I could refute all your claims but I’m not going to do all your homework for you. I would suggest you start with a good book on nutrient metabolism. First of all, your body does not ravage muscle once it is keto-adapted, muscle tissue is actually preserved on a well-planned keto diet. There is plenty of evidence to support this. Secondly, the brain can function very nicely on ketone bodies. It does not require lots of glucose. The only cells that are completely reliant on glucose are red blood cells and gluconeogenesis supplies their needs. Thirdly, there are current published studies demonstrating diabetes remission with a keto diet (Virta Trial). The American Diabetes Association is now finally acknowledging that a very low carb diet is the most effective dietary pattern to manage diabetes. In fact, they have three sessions on this topic being presented at the next conference in June 2019. Unfortunately, the Canadian Diabetes Association is way behind the curve in acknowledging this research. Lastly, try to find one study that demonstrates better weight loss on a low fat, calorie-restricted diet versus a very low carb diet. That study does not exist! I would suggest two books for your professional reading (both written by Dr. Jason Fung, a nephrologist in Toronto) — The Obesity Code and The Diabetes Code. Both are very well-referenced.

    1. If you believe Jason Fung is a good quality source of information on ANY subject you’re the one who needs to do some more research.

      Finally Angela, you’re entitled to your opinions. I believe your beliefs in this diet are premature and that by putting faith in people like Fung you’re being misled. I’ve been in rooms with you where you’ve been asked for RCTs on this diet and you’ve been able to provide none. Don’t come on my personal website, try to tear apart my work, then tell me you’re ‘not going to do my homework’ when asked for evidence. If this research is so prevalent you should have a stack of papers readily available to prove your point.
      I made it very clear in my article that low carbohydrate diets have some use and function. Your response above suggests you did not actually read my article in full.

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