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).
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.
How To Measure If You're In Ketosis
Benefits/Drawbacks of the ketogenic diet compared to other diets.
- Weight Management
- Heart Health and Cholesterol
Benefit: Weight ManagementThe 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 CholesterolUnfortunately, 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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