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The Fitties Blog

The Basics of the Ketogenic Diet

March 02, 2023 | Supplements and Nutrition

The number of nutrition guides and lifestyles out there are multitudinous to say the least, so how is a person to know which one is best for them? Well, first and foremost, discuss the options with your primary care provider. They are the ones best equipped to help you navigate and maintain your health.

Now with that being said, it does not mean you can’t do your own research, and given that the internet in all its vastness, is like taking a dive into a never ending well of information, you’re bound to find what you’re looking for. And since you’re here, that’s a pretty good thing because this is just one of the pit stops along the health and fitness research and information highway, from which you can glean material that is perhaps relevant to your health and fitness journey.

Paleo, vegan, vegetarian, pescetarian, flexitarian, lacto-ovo vegetarian and so on – all of these lifestyles are but a few which many people tout the advantages of. There is another one however, which plenty of people around the world have adopted, and it has in fact, been around for just under a century. Yes, you read that correctly – just under a century! 90 years to be exact.

I’m talking about the ketogenic diet. According to The Charlie Foundation the ketogenic diet was established in 1924 by a Dr. Russell Wilder of the Mayo Clinic, and was used as an extremely effective way to manage epilepsy. However, by the 1940s the diet fell to the wayside in lieu of anti-seizure medication. Many people still sing the praises of a ketogenic diet though and not just for its purported efficacy in treating epilepsy, but also as an overall weight loss dietary and fitness regimen aide.

What is a ketogenic diet?

A keto diet is one that is very low in carbohydrates and while there are other diets out there that also promote a low-carb approach, a keto diet also keeps an eye on the amount of protein a person consumes while increasing fat intake. The purpose of the ketogenic diet is to make the body burn fat by limiting its preferred energy source which is glucose – from carbohydrates, in order to bring about ketosis.

Okay, what’s ketosis?

Ketosis is a state of being that the body goes into when its primary fuel is fat. The body produces molecules of energy or fuel called ‘ketones’ which is used as an alternative source of energy when the body has an extremely limited supply of glucose from carbohydrates. Now, these tiny, little fuel molecules are synthesized in the liver by fat and they are then quickly guzzled up by the body in order to energize it, and, wouldn’t you know, it is especially tasty to the brain. The brain requires an incredible amount of energy which it typically derives from glucose but… it can also use ketones. The brain, being the hungry organ that it is, has to have an alternative source of fuel besides glucose, because think of it like this; we can only store glucose in the form of glycogen for energy for up to 48 hours or so, (for long term storage the body converts it into fat) and if glucose was suddenly in short supply, the brain would begin to pull it from muscles for energy so that it can survive. A survival mechanism of course! However, it wouldn’t be a very prudent thing to do as we would end up suffering from muscle wastage, and because the brain – smart and efficient organ that it is – knows that, it ensures it has a plan B – the ability to consume ketones for energy.

How does this help with exercise?

Okay, while it is true that many athletes, especially those who partake in endurance activities and events, will carb-load before said activities or events, more recently there has been an upswing in the adoption of a high fat/low carb diet in order to bring about similar results in energy metabolism for endurance events (those lasting for an hour or more, typically), to the results experienced when consuming high amounts of carbohydrates beforehand.

You see, high carbohydrate diets increase the amount of glycogen stored within muscles, as well as the liver and this in turn helps to bring about positive results with regards to how we perform in endurance events. This is great, though it does increase the amount of carbohydrates used during physical activity overall. Essentially, an endurance athlete would want to maintain their glucose stores for use during the latter parts of extended events or activities and maintain as even a stream of energy utilization as possible. So, what’s all this got to do with a ketogenic diet?

It has to do with opting for an alternative primary source for metabolism during exercise, and a ketogenic diet offers that. Studies that have been conducted on athletes who partake in endurance activities have shown that an extended period of ketosis allows for an adaptation to occur wherein the body’s preferred energy source becomes the fatty acids resultant from a high fat/low carb diet, and the rate of carbohydrate utilization is decreased, therefore increasing the overall ability to last longer during moderate to extremely exhaustive activities.

But physical endurance isn’t the only thing that improves when the body is fueled primarily by fat. It can also increase mental endurance. Sometimes when we neglect our diets, when we pay less attention to the foods we use to fuel up with, our focus and mental clarity can be affected. We can and often do, feel groggy, sluggish and perhaps even lethargic.

And when we talk about a high-fat/low-carb diet, I don’t mean sitting down to enjoy your meal of Crisco, or taking bites out of a sticks of butter for a snack. I mean fueling your body with the right fats; good, healthy fats.

It is important to obtain these fats; essential fats through food sources as we cannot synthesize these on our own. Understanding which sources of fat are the best options for a ketogenic diet, could mean the difference between better health and potentially harming it.

Which fats then?

  • MCT’s or Medium Chain Triglycerides – which are saturated fats that the body can digest quite easily, especially if it is being processed immediately for energy, as on a keto diet. An example of this would be coconut oil.
  • Monounsaturated Fatty Acids – such as oleic acid and omega – 9 are found in foods such as avocados, macadamia nuts, and olive oil.
  • Polyunsaturated Fats – such as omega – 3 and 6 are essential and the body requires their intake from outside sources. Polyunsaturated fats are derived from items such as olive oil, nut and sesame oils and should not be heated ideally, due to the fact that they can form harmful compounds when they react with oxygen during the heating process. Oils and dressings would be a good way to consume these.

Where does a person begin?

Okay, there are several kinds of ketogenic diet and the list is as follows:

  • Standard ketogenic diet (SKD) – typically consists of a carbohydrate intake comprising 5% of the diet, protein comprising 20% of the diet, and the fat content comprising 75% of the diet.
  • High-protein ketogenic diet – which is similar to the standard ketogenic diet, but you are allowed to increase your protein intake. Carbohydrates still comprise 5% of the diet, but protein will make up 35% of it, and fat comprises 60%.
  • Targeted ketogenic diet (TKD) – which is focused on adding carbohydrates around workouts.
  • Cyclical ketogenic diet (CKD) – is a diet that rotates higher carb days with ketogenic days. For example 2 days of higher carbohydrates days, followed by 5 keto days.

It is important to note that the only two diets that have been extensively studied are the Standard ketogenic diet and the high-protein ketogenic diet, as the others are opted for mainly by athletes, or people who partake in body building activities.

What foods should a person avoid on a keto diet?

Basically, foods that are high in carbohydrates are those that are limited. These foods include:

  • Sugary items – ice cream, candy, cakes, sodas, fruit juice etc.
  • Fruit – all fruit apart from small portions of those which are lower in sugar (e.g. tart berries)
  • Root vegetables and tubers – sweet potatoes, carrots, potatoes, turnips etc.
  • Beans and legumes – lentils, garbanzo beans, peas etc.
  • Starches and grains – rice, pasta, cereals and wheat based products
  • Alcohol – can have high carb content
  • Sugar-free or diet foods
  • Certain condiments and sauces – these often contain sugar and unhealthy fats
  • Unhealthy fats – processed vegetable oils or food products which contain these, such as mayonnaise

What should one eat on a ketogenic diet?

The majority of your meal plans, your diet, should be based on the following foods:

  • Fatty or oily fish – tuna, mackerel, trout, salmon etc.
  • Butter and cream – grass fed preferably
  • Avocados
  • Nuts and seeds – pumpkin seeds, chia seeds, sunflower seeds, walnuts, almonds, pecans etc.
  • Low-carb vegetables – mostly greens, leafy vegetables, tomatoes, peppers and onions
  • Herbs and spices
  • Healthy oils – coconut oil, EVOO (extra virgin olive oil), avocado oil
  • Cheese – unprocessed cheeses, blue cheese, goat cheese, mozzarella, cheddar
  • Eggs – 0mega – 3 whole eggs are a good option or pastured/free range eggs
  • Meat – ham, sausage, bacon, chicken, turkey, red meat

By eating foods that are as clean and as unprocessed as possible, you are able to provide your body with beneficial nutrients. In addition, eating clean and fresh allows you to prepare your meals from scratch and to get creative and find out what your likes and dislikes are. Maybe you really end up liking something you never thought you would. It opens up doors, not only to improved health, but also creative ones. Flex your culinary muscles!

What does a typical ketogenic day look like?

An average ketogenic day would probably stick to the SKD percentages; 5% carbohydrates, 25% protein and 75% fat.

Breakfast options can include:

  • Scrambled eggs with bacon or sausage or perhaps you forego the bacon and sausage and instead opt for avocado, salmon or little cubes of cheddar cheese with your eggs.
  • Low-carb porridge comprised of pumpkin, chia and sunflower seeds and served with coconut milk and a pinch of cinnamon for flavor.
  • Omelets and frittatas are another option, just find a version that doesn’t contain many if any carbs and get cooking!
  • Breakfast menagerie, which sounds chaotic, but it really is fun. You get to have a ‘little bit of lots’ and satisfy several tastes all in one sitting. On your plate you could put some cold cuts, slices of red peppers, slices of cheese or perhaps mozzarella balls, cucumber spears, and boiled eggs.

Lunch options can include:

  • Low carb wraps with chicken, lettuce, red pepper, and cheese
  • Salad with bacon, prosciutto, goat or feta cheese, and spinach, and kale
  • Chicken breast or fish with a garlic and herb butter
  • Fish curry with coconut milk

Dinner options can include:

  • Salisbury steak with a tomato sauce
  • Pork chops with creamy lemon and herb sauce
  • Meatloaf with bacon
  • Foil baked fish with lemon butter and Brussels sprouts

There really is wealth of opportunities for you to create a meal plan best suited to your lifestyle, while simultaneously maintaining a ketogenic diet. It might take a little research and a little planning, but if keto is a nutritional lifestyle you feel best suits you, then the research and planning could very well turn out to be some of the most exciting aspects of it!

Are there any side effects on a keto diet?

As with any dietary program or lifestyle there can be some adverse side effects that people have reported experiencing. These can include:

  • Headaches
  • Lethargy
  • Tiredness
  • “Brain Fog”
  • Irritability
  • Nausea
  • Leg cramps
  • Constipation
  • Induction Flu – most people who embark on a keto diet experience flu-like symptoms during the first week.
  • Bad breath – because this can be a sign that your body is burning significant amounts of fat, it’s important to ensure you’re hydrated. Your mouth might be dry which can happen when a person is on a strict low-carb diet, so again keep your fluid intake up and your sodium consumption balanced in relation to it.
  • Palpitations – can be due to lack of salt or dehydration, and a person can experience their heart beating harder as well.

These are all common symptoms that tend to resolve themselves within a few days or a week, and often it’s attributed to insufficient fluid intake and/or insufficient sodium due to increased urine output while the body is adjusting to a keto diet. Staying well hydrated during the first week and ensuring you are receiving an adequate amount of salt could help to minimize or eliminate these symptoms when transitioning into a ketogenic lifestyle.

Important Note for People with Health Concerns

There are certain conditions or health situations that require strict and very careful medical supervision when embarking on a ketogenic diet, or may prevent a person from undertaking a ket lifestyle completely. These include:

  • People with a BMI less than 20
  • Those who suffer from Pancreatic Insufficiency, as fats aren’t as easy to digest
  • People with metabolic problems or disorders that might compromise normal fat metabolism
  • Those with gallbladder disease or who no longer have a gallbladder, as fats aren’t as easy to digest
  • People with tendency to develop kidney stones, as they will have to ensure salt and fluid balance is maintained, and these can change when starting a keto diet
  • Children, as the protein consumption requirements vary for children, by their age
  • Pregnant or breastfeeding women, as protein intake recommendations and requirements are increased during these crucial periods
  • Those who have had gastric bypass surgery, as fats are more difficult to absorb

In addition, those who have diabetes need to be extra careful when adopting this diet as part of their lifestyle. Too much fat being burned can cause a dangerous situation to occur called ketoacidosis, which is when there is too much acid in the blood. Monitoring ketone levels can be done by using a ketone measuring strip as ketones flow over into the urine. Excessive or large numbers of ketones is something that is a big red flag.

Furthermore, those who are on blood pressure medications are urged to monitor their blood pressure more frequently, as a reduction of carbohydrates in the diet can and often does result in weight loss, which in turn can improve/lower blood pressure. If the reduction of blood pressure from weight loss occurs, and a person is still taking blood pressure medication, it can drop too low which is potentially dangerous – so the best thing to do is reach out to the appropriate healthcare professionals for advice!

It is very important to educate yourself and become informed from a licensed healthcare professional or medical provider so that you can ensure you are making the right dietary and lifestyle decisions for you.

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