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Keto Basics

Keto Basics

What is the Ketogenic Diet?

The ketogenic diet is a high fat, moderate protein, low to no carbohydrate diet. Contrary to popular belief, it is NOT a low carb diet. A low carbohydrate diet is commonly defined as a diet that supplies 50% or less of its calories from carbohydrates (Feinman et al.,2003). In comparison, a ketogenic diet typically contains 50 grams or less of carbohydrates, and most of those carbohydrates should come in the form of fiber (Paoli et al., 2013). The ketogenic diet macronutrients are distributed as follows:

To demonstrate the difference between low carb and ketogenic diets, Young and colleagues performed a study comparing the two diets. The scientists split young overweight males into 3 groups: 30 grams of carbohydrates per day, 60 grams of carbohydrates per day, and 100 grams of carbohydrates per day. Calories and protein were equal in all groups, and fat filled out the remaining macronutrients of the diet for all groups. The results showed that the group consuming 100 g group never achieved ketosis, 60g group achieved mild ketosis, and the 30 g group achieved optimal ketosis. Additionally, the 30 g group lost more fat than either the 60g group or 100g group (Young et al., 1971).

We’ve been told that carbohydrates are the primary source of energy for the human body, however, there is a more efficient fuel source that humans used to rely on more frequently before the rise of industrial agriculture. That fuel source is the mighty ketone.

The underlying concept of the ketogenic diet is that fuel utilization is switched from glucose (carbohydrate) to ketones. Ketones can rise in one of two ways. The first is to follow a ketogenic diet, while the second, is to intermittent fast. So how does the ketogenic diet induce the production of ketones?

When you restrict carbohydrate, you create a situation of low glucose, and low insulin. The human body recognizes this and begins to utilize glycogen stores (mainly in the liver) to prevent blood glucose from dropping too low. This produces a perfect environment for the body to tap into the energy reserves of adipose tissue, in order to release fatty acids into the blood to fuel energy production. The fatty acids then go to the liver, where a buildup of fatty acid leads to the production of ketone bodies.

Once in the liver, fatty acids will be used to create acetyl – CoA in order to enter the Kreb’s cycle for energy production. This will then lead to gluconeogenesis, the formation of new glucose molecules, to keep blood sugar levels optimal in the absence of any glucose intake. However, since fatty acids contain so much energy, they make acetyl – CoA too quickly. This leads to the formation of the ketone, acetoacetate, which then enter circulation to be used as a fuel source in place of glucose (since all of the glucose is being produced to keep blood sugar optimal, the body doesn’t have enough sugar to fuel other essential functions, so ketones are used as the replacement). This process of breaking down fatty acids into ketones, will lead you into ketosis.

What is Ketosis?

Ketosis is a state in which the body utilizes primarily fat as fuel and increases the production of ketone bodies. In order to get into ketosis, we need to lower our glucose intake, and increase our fat intake.

This shift in dietary intake describes the Randle Cycle. The principle of the Randle Cycle states that high intakes of carbohydrate inhibit fat metabolism, and high intakes of fat inhibit carbohydrate metabolism (Hue et al., 2009). This is why consuming a high fat, high carbohydrate is extremely detrimental to health, because both substrates inhibit the other leading to fat gain, decreased longevity, increased chance of metabolic diseases, and overall poor health.

It is important to understand the function of insulin in regards to ketosis. High insulin has a negative effect on ketone production; it actually stops the breakdown of fat, and therefore should stop ketone production. That is why avoiding carbohydrates (glucose) is crucial to the ketogenic diet; you are trying to avoid the secretion of insulin by not feeding the body any carbohydrates.

Many people who have consumed high amounts of carbohydrates for extended periods of time may also experience something known as insulin resistance. Imagine, 3 years ago, you could consume 10g of carbohydrates, and the body only needed to secrete 1 insulin particle in response. After consuming carbohydrates so frequently and for so long, today, you eat the same 10g of carbs, but your body now needs to secrete 5 insulin particles in response. Worst of all, the 5 insulin particles could only move 5g of carbs into functional cells, and the other 5g had to be stored as fat.

Ketosis helps to make the cells more responsive the insulin (cells become more insulin sensitive) and may reverse insulin resistance. A condition where you have high ketones and high glucose levels, produces an unnatural phenomenon known as ketoacidosis. Ketoacidosis is when you have high glucose, and high ketone production because of a lack of insulin, or an inadequate uptake of insulin into the cells causing glucose to stay in the blood (like in type 1 and type 2 diabetics). This causes the blood to be highly acidic and can lead to death. If you have healthy and properly functioning insulin, ketoacidosis won’t be an issue.

For healthy individuals, ketone production won’t go past 7 mmol/L. You’d have to experience ketone levels of 15 mmol/L or higher, while simultaneously have high levels of blood glucose. Lastly, lets touch on keto – adaptation, the period of time where your body switches fuel utilization from carbohydrates to ketones (Volek et al., 2015).

This is highly dependent on a few of factors: insulin sensitivity, exercise, dietary habits, and the number of mitochondria you have. During this time, you may experience almost “flu- like” symptoms, lethargy, and fatigue. This is good news, that means the body is slowing carbohydrate utilization, and switching to ketones. After this period of “flu” of a day or two, you’ll begin feeling normal again, although with slightly enhanced mental clarity.

Check your blood ketones, and if they are above 0.5 mmol/L, you have now become keto adapted. Recently, keto – adaptation has been found to be an ongoing process, continually making slow progressive changes over time (Volek et al., 2016).

How To Measure If You're In Ketosis

How to Measure Ketosis

You can measure ketones with one of three ways: blood, urine, and breathe.

Measuring ketones using urine strips, will monitor acetoacetate. This method may be misinforming. The body will excrete excess waste through urine. When ketones are excreted in the urine, this means there is an excess amount of ketones in the blood. If the urine reading is low, it does not necessarily reflect your state of ketosis, as you could actually be in ketosis, and efficiently using up ketones, so there really is no excess of ketones. Drinking lots of water, electrolyte status, and genetic variability to ketone usage, may all alter your urine test results. The advantage of measuring with urine strips, however, is that they tend to be a bit more affordable, and an easy quick check to see if you are on the right track when measuring urine.

Monitoring your blood ketones, you will be monitoring beta-hydroxybutyrate (BHB), the most common ketone the body may produce. To use this method, you will need to use a blood ketone meter. You will be required to prick your finger and provide a small droplet of blood on a ketone strip, which will then read out your ketone level. Since the blood cannot get altered as much as urine can, blood is considered a more accurate, and more consistent measurement of ketosis. However, be aware that blood levels may still fluctuate (although not as greatly as urine). This solution can also be more expensive than urine strips. 

Lastly, you can measure breathe ketones by monitoring acetone. Acetone is a byproduct of ketone utilization, and it is evidence that you have achieved ketosis because it confirms that you are in fact utilizing ketones. However, being a byproduct of ketone utilization, it is an indirect method of measuring your state of ketosis, while blood and urine are more direct. A study compared all three methods of measuring ketones. Measuring breathe acetone was a reliable predictor of blood ketones, and therefore ketosis, while urine predicted correctly, but severely overestimated the amount of ketones that were being excreted (Musa – Veloso et al., 2002). There are advantages and disadvantages to each type of measurement, which is why we are working to provide the complete solution for customers looking to measure if they are in ketosis! Stay tuned...

Benefits/Drawbacks of the ketogenic diet compared to other diets.

In 1925, the ketogenic diet was first used as a way to treat epilepsy in children (Peterman, 1925). Peterman saw improvements in his pediatric patients; reduction of epilepsy, increased mental function, and, surprisingly, weight loss. Since then, the ketogenic diet has developed many potential benefits. We’ll touch on only a few of the main topics:
  • Weight Management
  • Heart Health and Cholesterol

    Benefit: Weight Management

                  The ketogenic diet impacts weight management in two ways: hunger, and utilizing fat as fuel (keep in mind, a calorie deficit is necessary). Since we’ve already explored how fat is lost, we’ll focus on how the ketogenic diet controls hunger. Following a low – calorie, carbohydrate-based diet for eight weeks, participants hunger hormones stayed elevated, however, a ketogenic diet during the same amount of time did not increase hunger, and participants actually ate less (Sumithran, et al., 2013). This is most likely because there is no fluctuation (peaks, and drops) of blood glucose, and therefore insulin. In addition, fatty acids are circulating, and ketones are being used as fuel. The metabolic atmosphere doesn’t provide the body of any signals of hunger, so you do not feel hungry.

    Benefit: Heart Health and Cholesterol

                  Unfortunately, one of the most common medical misconceptions is that high fat intake causes high cholesterol, high triglycerides, and an increased risk of cardiovascular disease. Although triglycerides following a ketogenic meal will be elevated, it is only for a short period of time before they are shuttle away for utilization. Over time, they actually become lower and lower as the mitochondria become more efficient at using fat as fuel. Consuming high levels of carbohydrates and high levels of fat together is associated with elevated triglyceride levels, not consuming high fat alone (Retzlaff et al., 1995).

    The ketogenic diet has shown through numerous studies its positive effects of HDL (the cholesterol that brings fat to the liver, also considered the “good” cholesterol). However, this comes with an increase in total cholesterol, but that’s only because HDL has risen. Having more HDL to Total Cholesterol is a good predictor of heart disease risk (Lemieux, et al., 2001). The ketogenic diet increases HDL, causing a rise in the ratio of HDL to total cholesterol, indicating a lower risk of heart disease, not a greater risk (Westman et al., 2002). In addition, low fat diets have been shown to lower HDL and total cholesterol, which would decrease the ratio of HDL to total cholesterol and potentially increasing the risk of cardiovascular disease (Volek and Feinman, 2005).


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