What Is a Ketogenic Diet?
The basics of the ketogenic diet are as follows:
- Prioritize eating to satiety with dietary fat
- Maintain a low carbohydrate intake
- Consume moderate protein foods
The average keto diet recommends anywhere from 20-50 grams of net carbohydrates per day but isn’t typically an eating pattern where followers count calories or macros (1).
Proponents of the keto diet claim it can help you lose weight, decrease cravings for junk foods and sugar, and increase energy levels.
Benefits of a Ketogenic Diet
The keto diet has actually been used by physicians and nonphysicians alike for about 70 years. What began as a way to manage seizures in children who were unresponsive to medication, has become a huge boom for those who want to lose weight or for whom other methods of weight loss haven’t yielded results.
Research supports several benefits of a ketogenic diet, including (2, 3):
- Increased autophagy
- Better insulin sensitivity
- Healthy blood sugar balance
- Supports liver health
- Lower long-term triglycerides
- Better ratio of HDL to LDL cholesterol
Anecdotally, those who follow a keto diet say they have better energy, increased mental clarity, and don’t feel the pull of previous cravings.
Types of Keto Diets
You’ll find there’s more than one way to participate in the ketogenic diet, and that there are many ways to incorporate a low carb, high fat style eating pattern into your life.
Typically, a ketogenic diet isn’t followed 24/7 or all year round, and this is for important reasons we’ll discuss in a moment. But first, let’s take a look at the different types of a ketogenic diet.
Cyclical
A keto diet can be tailored to suit your needs by following a cyclical pattern. This means you may be in ketosis for 2 weeks at a time, followed by a 3 to 4 week “break”.
This doesn’t mean you return to eating the Standard American Diet during this break, but that you increase your carbohydrate intake slightly by incorporating healthy sources such as sweet potatoes, more vegetables, and some unrefined grains like rice or quinoa.
The cyclical pattern can be adjusted to suit your needs and is often accompanied by intermittent fasting. You can also maintain a keto diet during the week, and allow a more relaxed approach on the weekends. The time period is flexible based upon what works best for your body.
Seasonal
Proponents of a seasonal ketogenic eating pattern often overlap into ancestral eating styles, so as to mimic periods during the year where rich sources of carbohydrates like fruits and vegetables may not have been available due to cold temperatures.
Supporters of this theory state that as temperatures drop, daylight decreases and humans are less active, we’re naturally suited to consuming food less often and the ketogenic diet aligns with this natural ebb and flow in food availability.
Can There Be Too Much of a Good Thing?
Being in a state of constant ketosis is contraindicated in almost every situation, save for those where it’s medically necessary and you’re under the supervision of a trained physician.
Remaining in ketosis constantly can put stress on your adrenal glands, thyroid, and endocrine function–especially if you’re female.
What Does It Mean to Be in Ketosis?
Ketosis is the word used when your body is actively burning body fat for fuel. When dietary carbohydrates are limited, your body will eventually be forced to oxidize stored body fat and break it down into free fatty acids that then become ketone bodies.
These ketone bodies are then used as fuel for your brain or muscles, but they’re not stored afterward, and you’ll excrete them in your urine.
When measuring to find out if you’re in ketosis, either blood, urine, or breath tests are used to measure the level of ketones your body is excreting. This provides some insight as to whether your body is using its own fat for fuel.
Do You Have to Measure Ketones on the Keto Diet?
You may hear that it’s necessary to measure your ketones if participating in the keto diet, but it’s still very possible to achieve the benefits of the keto diet without measuring ketones.
A low carbohydrate and high fat diet, even without measuring ketones still supports insulin sensitivity, healthy weight loss, blood sugar balance, and mitochondria health.
Keto Doesn’t Mean ‘Carnivore’
Contrary to popular belief, a ketogenic diet followed correctly is not only consuming meat and cheese. In fact, limiting yourself in this way can often lead to nutrient deficiencies, and you’ll miss out on important phytonutrients like astaxanthin, lutein, or lycopene.
The ketogenic diet prioritizes healthy, whole-food sources of carbohydrates such as leafy greens, asparagus, cruciferous vegetables, and some low-carb root vegetables such as turnips or rutabaga.
The “Keto Flu” and Other Problems
Often, those who choose to follow a keto diet eventually encounter certain issues like the “keto flu”. When this happens, your body often feels achy, you may have mood swings, feel tired, and have difficulty concentrating.
The keto flu usually happens after 1-2 weeks of following a ketogenic diet. Most likely, the keto flu is a combination of your body adjusting to fewer carbohydrates, which means no quick and easy sugar-fixes, and a decrease in stored minerals since losing water weight is common during the initial phase.
How to Combat the Keto Flu
Staying properly hydrated is paramount throughout your keto diet journey, but especially in the beginning.
Replacing electrolytes such as magnesium, potassium, and chloride is essential. You can use a salt supplement, or drink bone broth to replace minerals.
You can also supplement with MCT oil as your metabolism slowly adjusts to using more fats for fuel instead of carbohydrates.
Does Keto Impact your Thyroid or Adrenal Glands?
Some people do report changes in their thyroid panels after following a ketogenic diet. There are a few reasons why this could be.
First, calorie restriction has been shown to lower thyroid hormone, simply because your thyroid acts as a metabolic barometer (4). In times of excess, your thyroid is active, and in times of restriction, it’s less so.
Second, a ketogenic diet high in PUFAs or polyunsaturated fatty acids has also been shown to reduce metabolic response to T3 (5). Another study showed rats fed high-fat diets containing corn oil converted less T4 to active T3 (6).
This may indicate the type of fat you consume while following a keto diet has some impact on your thyroid.
Does Keto Raise Cortisol Levels
When carbohydrates aren’t available, your body can produce increased cortisol in an effort to raise blood sugar. If you have a history of chronic stress or adrenal dysfunction, slowing your transition to keto and incorporating plenty of healthy sources of fiber can help maintain adrenal health.
How to Start a Keto Diet
If you’re a beginner looking to explore how the ketogenic diet can help you lose weight, decrease sugar cravings, and improve your health, here are some simple tips to get started.
- Remove high-carb and processed food from your fridge and pantry. If your aim is to change your diet, you first have to remove the temptations that are likely to rear their head if given the chance.
- Replace with high-fat, keto-friendly options. Included in the list below are some simple and easy keto foods that can fit into almost anyone’s lifestyle.
- Satisfy your hunger with fat. It can be challenging to change your mindset around fat since much of conventional dogma dictates that fat is a negative thing. But if you want to succeed on a ketogenic diet, you’ll have to first choose calories that come mainly from fat.
- Focus on whole-food, healthy carbs like low-carb veggies, and low-sugar fruits. When cycling out of a keto diet, you can comfortably eat minimally processed grains, potatoes, and sweet potatoes, and still indulge in your favorite occasional treats.
Keto-Friendly Foods
A healthy ketogenic diet will focus primarily on whole-food items that are minimally processed. In some stores, you can find prepared foods and snack items that are “keto-friendly” but these convenience foods shouldn’t make up the majority of your diet.
Keto and Functional Medicine
The ketogenic diet is one that can have many benefits when followed correctly, but many beginners in this eating pattern can fall short of adequate nutrition and difficult metabolic changes they’re unprepared for.
When you’re thinking about making a significant change to your diet, your functional medicine doctor can help guide you through the optimal ketogenic diet experience that fits your needs, biology, and lifestyle.
Resources
- https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/ketogenic-diet/
- https://www.acpjournals.org/doi/full/10.7326/0003-4819-140-10-200405180-00006
- https://www.acpjournals.org/doi/abs/10.7326/0003-4819-142-6-200503150-00006
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2649744/
- https://pubmed.ncbi.nlm.nih.gov/2352037/
- https://pubmed.ncbi.nlm.nih.gov/3705/