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The Low Carbohydrates Healthy Fats (LCHF) Ketogenic Diet
The SCIENCE of the KETOGENIC DIET (CLICK to Expand)
You probably have heard of the so-called "ketogenic diet," or the "keto diet" in short. But you may not be that very familiar with it, and what it’s supposed to be. Would you like to understand more what the "keto diet" really is? Well, you've come to the right place, AND it's good to find you here because in this article, that's what we are precisely going to do! Let's dissect what really is the "ketogenic diet," and what good can it do for you!
"KETO" DIET IS FAD?
Many have considered the "keto diet" as just another "fad" diet - particularly one that was supposed to promise quick weight loss and lesser body inflammation. Well, I would tend to agree that indeed, it could be just a “fad” diet for you - especially if you really don’t know what it is, and what’s the real deal of the science behind it - most probably because you are doing it just for the kicks, perhaps to “go with the trend” or to “follow what your friends are doing” from what they’re posting in Facebook and YouTube. However, I’m here to tell you that there’s a whole world of science behind it, and you should know what that science is all about, so that you can properly decide if the “ketogenic diet” is good enough for you!
First things first. The "ketogenic diet" is actually part of the spectrum of diets that fall under the "low carbohydrate diet" category. Compared to other low carbohydrate diet regimens, a low carbohydrate ketogenic diet (LCKD) is considered among the ones containing the lowest consumption of net carbohydrates at less than 50g per day. A much lower daily carbohydrate allocation of less than 30g is expected for the very low carbohydrate ketogenic diet (VLCKD).
WHAT MADE THE “KETO DIET” KETOGENIC?
With its low to very low carbohydrate content, the ketogenic diet was named as such because of its tendency of making the body go into a state called "nutritional ketosis." Different macronutrients elicit different levels of insulin response from the pancreas. Of course, carbohydrates elicit the highest levels of insulin in the blood. Fats have the least insulin response, with proteins somewhere in the middle. So with very low carbohydrate food intake, the insulin level in the body doesn't rise as much, and with low levels of insulin, the metabolic process of "lipolysis" is activated, thus leading to the release of fatty acids from the body's fat stores. Excess fatty acids are brought to the liver where they are catabolized to ketone bodies, specifically acetoacetate, acetone and 3-beta-hydroxybutyrate.
A BRIEF HISTORY OF THE KETOGENIC DIET
So how did we first come to know about the “ketogenic diet”? Physicians first used the so-called "ketogenic diet" for the treatment of epileptic patients in the 1920s. So, we neurologists are quite familiar with this. However, prior to this, for over two thousand years since at least 500 BC, fasting has already been known as a way of treating different ailments, including epilepsy as noted in the Hippocratic Corpus. The ketogenic diet was originally meant to imitate the benefits of fasting, particularly the production of ketones, in the liver. This was especially embodied in the works of Drs. Geyelin, Woodyatt and Wilder in 1921. It was Dr. Russell Wilder who first designated the term "ketogenic diet" to such dietary intervention, and by 1925, Dr. M. G. Peterman of the Mayo Clinic reported in the Journal of the American Medical Association (JAMA) a "ketogenic diet" formulation that is much similar to what is being used today, and which was meant for epileptic children, consisting of daily allocations of about 10-15g carbohydrates, 1g per kg body weight of protein, and the remainder as fat calories.
However, in 1938, when the anti-seizure properties of the drug diphenylhydantoin (more commonly known as phenytoin) was discovered by the neurologists Dr. H. Houston Merritt and Dr. Tracy Putnam, the use of the ketogenic diet among epileptic patients gradually waned and fell by the wayside.
WHAT IS THE KETOGENIC DIET FOR?
Let's talk just a little bit of science here. As a very low-carbohydrate form of low-carbohydrate diets (LCDs), the "ketogenic diet" mimics a lot of the biochemical scenarios of fasting. Hence, with the very minimal levels of carbohydrates and the relative abundance of healthy fats, the secretion of the hormone insulin by the beta cells of the pancreas is kept at low levels.
One of the basic functions of insulin is the inhibition of hormone-sensitive lipase (HSL) - which is an enzyme in fat cells that breaks down fats through hydrolysis (otherwise known as "lipolysis"). This results in the release of free fatty acids. Low levels of insulin encourage the body to enter what is called a “fat-burning mode.” This is further enhanced by elevated levels of the hormone glucagon.
Fatty acids may be used as a source of energy by certain body tissues including your skeletal and heart muscles, as well as the liver. However, the brain does not utilize fatty acids for its energy needs, thus it would need ketones. When there is high level of free fatty acids in the blood, and in the background of low levels of insulin, these fatty acids are then brought to the mitochondria of the liver, where they are catabolized or broken down into ketones.
Ketones are then used as fuel by the neurons of the brain, as well as the cells of the skeletal muscles and the heart. The low levels of glucose are then primarily allocated for the cells which do not consume ketones – such as your red blood cells (RBCs).
NUTRITIONAL KETOSIS vs KETOACIDOSIS
Perhaps you may have heard of "ketoacidosis," and you might wonder how is "nutritional ketosis" different from "ketoacidosis"? Ketones are continually produced in the liver, though at different rates depending on the level of dietary carbohydrates and proteins. Among individuals following diets high in carbohydrates, insulin levels are high enough to inhibit the breakdown of fat, and blood ketone concentrations are usually below 0.3 mmol/L. For those maintaining a well-formulated "ketogenic diet," the usual ketone concentration is somewhere between 0.5 to 2 mmol/L. And such well-formulated ketogenic diets usually limit daily carbs to within 30-50 grams, and proteins between 1.2 to 2 grams per kilogram body weight.
Ketosis is a physiological state that is considered within normal. Although ketone bodies are acidic, in low levels of nutritional ketosis, the body's strict buffering mechanism can effectively deter the development of metabolic or anion gap acidosis. As Dr. Ben Bikman has said, the body defends its blood acid or alkaline levels so well, it takes a very significant amount of insult for it to go haywire. So you need not worry about developing ketoacidosis when you are just keeping yourself well within levels of "nutritional ketosis."
On the other hand, "ketoacidosis" occurs when there is very high pathological levels of ketone bodies in the blood. And when does this happen? This may usually be encountered in patients with Type 1 Diabetes, where there is pathological absence of insulin production by the pancreas (called diabetic ketoacidosis or DKA), especially in those not strictly compliant to insulin treatment, and which leads to very high levels of free fatty acids that are shunted over to the liver for ketogenesis or the production of ketones. Ketoacidosis may also occur in excessive alcohol binge consumption (which is called alcoholic ketoacidosis). After ethanol is metabolized to acetic acid, this is then shunted to ketogenesis especially when insulin level is low and glucagon level is high. This may occur when excessive intake of ethanol is coupled with decreased food consumption due to vomiting, thus leading to episodes of low blood glucose or hypoglycemia.
HOW DOES THE KETOGENIC DIET WORK?
As you probably have known by now, I advocate a very low carbohydrate ketogenic diet (VLCKD) for the reversal of the so-called metabolic syndrome, or insulin resistance. The so-called "ketogenic diet," which as previously noted, maintains daily carbs of around 30-50 grams and 1.2-2 grams protein per kg body weight, effectively limits the rise of the level of insulin in the bloodstream. Since insulin resistance is characterized by chronic elevations of serum insulin, or what is called hyperinsulinemia, the sustained decrease in blood insulin levels brought about by the "ketogenic diet" somehow gradually reverses the effects of the so-called "insulin resistance syndrome" or the "metabolic syndrome."
How does this happen? Hyperinsulinemia, when it becomes chronic, eventually promotes the development of insulin resistance, thereby leading further to the manifestations of the Metabolic Syndrome. Various studies have shown that the pathology of chronic hyperinsulinemia is vascular in nature, thus hyperinsulinemia is itself at the core of the development of atherosclerosis, lipogenesis and its subsequent state of obesity, and the evolution of Type 2 Diabetes. I will be discussing these in more detail in another video.
And since it looks like chronic hyperinsulinemia indeed seems to be at the bottom of it all, finding a means to effectively curtail the levels of insulin would then effectively work towards the reversal of Metabolic Syndrome itself. And that's where the role of low carbohydrate diet regimens come into play.
SOME CAVEATS TO THE "KETO" DIET
However, if you have any of the following medical conditions listed here, do be extra careful when trying to go on the ketogenic diet. And discuss your options properly with a well-informed physician or medical professional. What are they?
Those with psychological eating disorders like anorexia or bulimia nervosa;
Pregnant and breastfeeding women;
Children and adolescents who are still in their growing up years - though I advocate having them eat whole non-refined unprocessed foods, and to make them avoid refined sugars and carbs, and not to just let them have high-carb snacks every so often even if they’re not really hungry;
Those with severe diabetes - both Types 1 and 2 – more so in those with severe complications such as irreversible end-organ damage in the kidneys; and
Those taking certain medications that may conflict with the state of nutritional ketosis - like certain antipsychotics such as quetiapine, risperidone, and aripiprazole (which may increase insulin levels in some people), as well as certain anti-diabetic medications which could result to severe episodes of hypoglycemia when taken together with a glucose-lowering ketogenic diet.
In patients with Type 2 diabetes, this is where you need to partner with a well-informed medical professional to help you out with a medically-guided therapeutic ketogenic dietary intervention, wherein your anti-hyperglycemic medications may gradually be decreased, and perhaps even stopped or de-prescribed if deemed appropriate depending on your compliance.
When we know that obesity and Type 2 Diabetes are now established at epidemic proportions worldwide, and this is by all intents and purposes much related to the development of insulin resistance and its corresponding Metabolic Syndrome, I suppose at this point, we REALLY need to redefine what is supposed to be a “healthy” diet. Is it what government health “authorities” define as “healthy” based on guidelines they make and promote? Or is it that kind of diet that will TRULY optimize our body’s metabolism and longevity?
Lastly, some patients have asked me: what about intermittent fasting or IF? What is it? Can I combine it with my LCHF or keto diet? In a nutshell, intermittent fasting has its own good points with or without keto. But I guess that would take us much time here, and that would be worth a topic for another video - so watch out for it soon!
I hope I got you the answers to all those questions brewing in your head about the ketogenic diet. Like the YouTube video above and share it with your friends! Subscribe to the Low Carb Health Doctor | LCHD channel!
LCHF KETO DIET: Which Foods are HIGH Carb? Which are LOW Carb? (CLICK to Expand)
People have asked: I'd like to start on a ketogenic diet, but how do I do it properly? Can I stick to it? This may be a question going on in your mind right now, that's why you are browsing this article. Yes, there could be a lot of confusion going around about what the ketogenic diet is, and how to implement it properly for your optimum benefit. That's why you need to understand it to be more effective in applying it to your own lifestyle! Read on and find the answers to that question! 👍
THE QUESTION: WHICH FOODS ARE LOW CARB? WHICH ARE HIGH CARB?
Every now and then, I encounter patients with serious misconceptions about which foods are truly low carb. For instance, not just once did I encounter patients who replaced their rice or muffin at breakfast with oatmeal, believing that oatmeal is low carb and "healthy" all the way. I cannot fault them - I guess you yourself have seen the American Heart Association's "heart healthy" logo printed on its packaging! I remember another patient who thought that sweet potato would be a nice alternative to keep blood sugars low. With these misconceptions, it's no wonder why certain "low carbers" still don't get the most optimum blood sugar control.
WHAT IS A LOW CARBOHYDRATE "KETOGENIC" DIET?
So what again is a ketogenic diet? It is a kind of diet that emphasizes restriction of dietary carbohydrates often for therapeutic purposes, which means you maintain a very low carbohydrate consumption in your daily diet. And that is meant to bring about a state of "nutritional ketosis" in your body. When you are in nutritional ketosis, you have a certain appreciable level of ketones coming from the breakdown of your body fat into ketone bodies - mostly beta-hydroxybutyrate and acetoacetate. How does it work and what is the whole science behind it? You may read the article on the Science of the Ketogenic Diet above, and you might want to watch this YouTube video about it. To become successful in arriving at the ketogenic diet's end-goal - which again is reaching that state of nutritional ketosis, the most important thing to always bear in mind when planning each and every one of your meals is to stick to foods that are truly low in carbohydrate content.
To hit that state of nutritional ketosis, it is recommended that you keep your net carbohydrate intake to a ceiling maximum of 30-50g per day. So that means you go for either a low carbohydrate ketogenic diet (or LCKD), or perhaps better still, a very low carbohydrate ketogenic diet (or VLCKD). For VLCKD, that means keeping your daily net carbohydrate intake to a more strict level of LESS THAN 30g per day. Don't worry about that very low carb - because carbohydrates is NOT an essential macronutrient for your body! By that, I mean to say that even if we do not eat carbs, our bodies can manufacture glucose in the liver through the process called gluconeogenesis. This, however, doesn't apply to certain basic amino acid building blocks for proteins as well as some fatty acids - which our bodies cannot create thus we need to supplement them in our diet. Knowing this, some people even push their diets further by totally consuming foods that have zero carb content such as what has been called the carnivore diet.
So now, how do you keep your daily carbs within 30-50g max? Most basic would be having a good idea about how much net carbs would there be in the foods that you usually eat. Take for example a teaspoon of sugar - would you know how much carbs does it have? Well, that's about 4g of net carbs per teaspoon. So how about one hamburger bun? Just the bun? Now for every bun which, let's say, weighs 46g on the average, that easily translates to a net carb of about 22g! Now compare that with your daily quota of a maximum of 30-50g of net carbs to maintain yourself on nutritional ketosis in a keto diet, and you'd more or less have a good idea about which foods to eat and which foods to avoid. With just a cup of rice containing about 44g net carbs, you have certainly reached your quota of carbs for the day! Same with two regular sized hamburger buns! And on top of that, you'd probably be eating some other foods that have their own levels of carb as well. So, if you are not aware of the carb contents of the foods that you eat, you could easily fall out of ketosis as well.
HIGH, MODERATE AND LOW CARB FOODS: A TABULATED GUIDE
You may look at the food list in tabulated form above. It segregates foods that contain high carb, medium carb and low carb. Arbitrarily for the purposes of our illustration here, let's say low carb foods should contain less than 6g net carbs per 100g volume. High carb foods would contain more than 10g net carbs per 100g. Somewhere in between those figures would be, let's say, medium carb content. The RED box (signifying "STOP") contains a list of high carb foods. The GREEN box (which signifies "GO") would have foods low to very low in carbs. And in the middle, the ORANGE box (signifying "CAUTION") would contain foods having carbs in moderation.
RED BOX (STOP!): HIGH CARB FOODS
So let’s go for a run-through - the RED BOX. What foods are obviously HIGH in carbs? Among the most notorious would be the sweetened drinks and beverages that abound at just about every convenience store round the corner. You have soda or soft drinks, fruit juices that come either canned or bottled, iced tea, milk tea, those that come disguised as energy drinks, and you have alcohol-containing drinks. Grains are of course high carb. You have wheat, corn, rice, barley, oats, rye, so on and so forth. The processed food products that are made from wheat flour are definitely high carb - all kinds of bread, cereals, cakes, cookies, biscuits, buns, chips, tortilla, don't forget the pasta - you have spaghetti, fettuccini, macaroni, and of course, also the noodles and the ramen. Certain fats and oils are not good for keto - especially the unhealthy trans-fats such as the hydrogenated or partially hydrogenated oils like that found in margarine, and Crisco is a good example. The oils that contain high levels of omega-6 to omega-3 ratio, are hypothesized to increase inflammation and perhaps even worsen insulin resistance. These include seed oils, or what has been cleverly hidden behind the seemingly healthy name "vegetable oil." They are mostly made from canola, corn, cottonseed, grapeseed, rapeseed, safflower, soybean and sunflower. Manufactured milk and dairy products also have high carb content - you have condensed milk, skim milk and ice creams high in sugar. Many fruits have high content of the simple sugar called fructose, aside from glucose. You have your good old apple - well, an apple a day may keep the doctor away - in some cases, just don't overdo it! You also have bananas, cherries, dates, durian, grapes and not to mention the dried grape product called raisins. You also have jackfruit, kiwi, lychee and rambutan, mango, orange, pear and pineapple. Nuts high in carbs include cashews and pistachios. Vegetables may be classified as either above-ground and under-ground, and those that come from underground sources called tubers are mostly starchy - such as potatoes, cassava, sweet potatoes or what Filipinos call "camote," and yams, include the purple yam or what is commonly known as "ube" in the Philippines. Certain legumes are high in carbs, including chickpeas, black beans, green peas, kidney beans, lentils and mongo beans. Some herbs and spices are also high carb for their equivalent 100g volumes - such as garlic, ginger, pepper, rosemary and thyme. However, you don't usually mix that many herbs and spices in your food, so its volume is usually quite negligible. And of course, ALL sugar sweeteners are high carb - both the white and brown sugar, as well as muscovado sugar. Other sugar-containing sweeteners that have to be avoided include agave from cactus, honey, maple syrup, fructose, and the always ever-notorious high fructose corn syrup (or HFCS).
GREEN BOX (GO!): LOW CARB FOODS
Now let's go take a look at the GREEN BOX - it contains low carb foods which for our practical purposes in this video means having LESS THAN 6g carbs per 100g food mass. Non-sugar containing drinks like your good ole' water, as well as sparkling water that may either have added lemon, lime or apple cider vinegar, are low carb. That also includes tea and black coffee, with the option of putting high-fat cream. Pure cocoa drink, almond milk, as well as coconut cream are also in this list. Among plant-sourced oils - avocado oil, coconut oil and olive oil are best for keto. The unprocessed or least processed extra virgin olive oil variant is better than the processed regular olive oil. Animal sourced fat such as lard from pork and tallow from beef are also rich in healthy saturated fats. Dairy products such as pure unprocessed cheeses, heavy cream and full fat yoghurt are low carb. If you have to drink milk, I recommend fresh milk which contains about 4.9g net carb per 100mL, but in moderation. Avoid the manufactured milk products like condensed, evaporated and powdered milk, which all contain much higher carbohydrates. All kinds of meat are okay with keto. That includes pork, beef, lamb and game, but choose grass-fed sources if possible. All kinds of poultry such as chicken, turkey, duck and ostrich are also okay, as well as all fish and seafood. Be a little bit careful though with mussels and oysters, they have a little more carbohydrates coming from glycogen as compared to other seafoods. For strict vegetarians and vegans who would like to keep themselves at ketogenic levels, tofu and tempeh which come from soybeans are good options. Fruits low in carbohydrates would include avocado, star fruit (or what Filipinos call "balimbing"), as well as berries like blackberry, raspberry and strawberry. Most of the above-ground vegetables are low carb. You have asparagus, bamboo shoots, broccoli, brussel sprouts, cabbage, carrots, chayote, cucumber and gourds, such as the bottle gourd and the bitter gourd. They are called "upo" and "ampalaya" in Filipino. All green leafy vegetables are low carb, such as arugula, bok choy, celery, chard or what is called "pechay" in Filipino, kale, spinach and water spinach or "kangkong" in the Philippines. There's also jicama, as how Mexicans pronounce it, having originated from Central or South America, but which is called "singkamas" by Filipinos. You got mushrooms, okra, olives, pumpkin, radish, squash, turnip and zucchini. A number of legumes are low carb, including edamame, green beans, snap peas, snow peas, soybeans and string beans. Some herbs have low carb content - those include basil, cilantro and parsley. If you need condiments, fermented foods like vinegar, kimchi, pickles and sauerkraut are all low carb. You may also have full fat mayonnaise - just check the ingredients and nutrition facts if they have added sugar and how much is it. There are also salad dressings without sugar. If you need to sweeten your food or dessert, I suggest you use plant-based non-sugar sweeteners like monk fruit which contains mogrosides, and stevia which comes from the stevia plant containing steviol glycosides.
ORANGE BOX (CAUTION!): MODERATE CARB FOODS
Now here in the ORANGE box, there are certain foods that contain a moderate amount of carbs thus you need to be careful of the total amount you consume. I earlier mentioned fresh milk which contains about 4.9g net carbs per 100mL. Some fruits may be a bit tolerable as long as you watch out how many servings you consume - you have apricots, cantaloupe, cranberry, dragonfruit, grapefruit, honeydew, lemon, lime, nectarine, papaya, passionfruit, peach, plum, pomelo and watermelon. You need to be wary of certain nuts and seeds like almond, peanuts, walnut, hazelnut, pine nut and sunflower, as well as nut butters made from them. For vegetables, you need to be a bit wary of artichoke, cauliflower, eggplant, leek and onions - both red and white. Be careful of some salad dressings especially if they contain some sugars and starches, as well as some non-sugar sweeteners like maltodextrin, maltitol and sorbitol.
You can have access to the PDF file of this food list HERE. You can get a free copy of that list I made by clicking on the link I provided in the description below. Or better yet, if you want to continuously learn more about the low carb lifestyle, the ketogenic diet and intermittent fasting, and how I am actively using it to address Metabolic Syndrome and improve the metabolic health of my patients, I invite you to become a member of this group (flash onscreen) - the Low Carb Health Doctor KETO Lab. You can access the LINK to the KETO Lab group by CLICKING the banner below.
THE BALL IS IN YOUR HANDS!
Now I’ve given you a list of foods that either help you attain metabolic health, or perhaps worsen it in due time. If you have the genes that enhance your risks of easily developing Metabolic Syndrome, your life’s journey will easily lead you that way if you allow it. That’s a daily choice that you NEED to make. That will empower you to eat and become healthier each day, OR you go the opposite way. That’s now your choice, your personal responsibility.
I hope I have helped you in whatever way in your own keto journey. If you think this article (and its YouTube video) will help you and your friends lead healthier lives, feel free to share it! Subscribe to my Low Carb Health Doctor | LCHD YouTube Channel and get notified of my upcoming videos by clicking on the channel's notification bell. Let's go Livin' La Vida LowCarb! 😇