The following article was written by Skip Franzsen, South Africa and published on this website on 26 Nov 2015.
We spotted this video, ‘What causes insulin resistance?’, and it is a useful representation of what insulin resistance is at a cellular level. More on the complexity of insulin resistance pathways are contained in this article by Luca and Olefsky called ‘Inflammation and insulin resistance’ (2008, see Figure 1 in their article).
In the video ’What causes insulin resistance?’, fats restrict the normal function of getting glucose into the individual cell creating an “insulin resistant” cell. That cell, having restricted access to glucose, will have less energy. According to Professor Jeff Volek, in ‘The many facets of keto-adaptation: health, performance and beyond’, insulin resistance is highly personalized at a cellular level. The level of insulin resistance is a growing epidemic which he estimates may be as high at 50% of the American Population. The type of processed carbohydrates and sugars contained in modern western society is the leading cause. Modern western diets are glucose burning diets, because carbohydrates (read glucose) are freely available as processed foods. In the history of the human species, most diets over many millennia have been fat-burning ketogenic diets.
“Normal body cells are able to create energy by using the food we eat and the oxygen we inhale to complete normal cellular “respiration” and make ATP (adenosine triphosphate), our main cellular energy source. Most of this energy production happens in the cell mitochondria, tiny organelles which act as cell fueling stations [in each individual cell]” (‘Ketosis: Metabolic Flexibility in Action’, no page number).
Having looked at ‘What causes insulin resistance?’, we must now ask what is wrong with the proposed treatment at the end of the video? According to the video, the solution to insulin resistance is a low fat high carbohydrate diet. However a low fat diet is unlikely to work effectively as a treatment for insulin resistance if that person is already insulin resistant.
The reasons should be obvious.
We have two primary types of food-based fuel that our cells can access as sources for energy: fats which do not require insulin to get energy into cells, and carbohydrates that breakdown into glucose or blood sugar and which largely require insulin to be used by the cells.
If you restrict fats by way of a low fat diet, it would require that you eat higher levels of carbohydrates (ie glucose or blood sugar) to supply overall energy. You cannot restrict both fats and carbohydrates in a balanced diet as this will lead to starvation.
And here is the core problem. The low fat and high carbohydrate diet is ineffective if you are already insulin resistant. Your insulin-resistant cells resist the cure. The high carbohydrate load spikes blood glucose and spikes insulin levels. Insulin resistance in cells ensures that higher blood glucose is not taken up effectively by the body. The unused glucose has to go somewhere and it eventually gets processed into fat reserves via the liver. In effect if you are already insulin resistant, a low fat and high carbohydrate diet will be ineffective.
But what if there is an alternative, not considered in the presentation above? What if you can effectively get energy into cells by bypassing the need for glucose as a fuel source and insulin’s function altogether?
A second type of cellular fuel is ketone bodies, which are created in the liver from the breakdown of fatty acids. Intake of fats do not spike insulin at all. Ketones are ancient pathways to process fats into energy and are naturally made as alternative fuels in the absence of glucose. For Ancient Man this was the primary fuel pathway. Ketones are produced from the fats we eat or from the metabolism of stored fat from our fat cells. If, via a diet, you restrict glucose enough and create ketones, you supply your cells with fuel via this alternative ketosis pathway. In simple terms, free fatty acids move into the blood stream where they are bound by serum albumin and transported to the cell needing fuel. Once the fatty acids reach the target cell, they are released by serum albumin and cross into the cell cytosol effectively bypassing Insulin resistance and getting energy via ketone bodies into the insulin resistant cell.
Ketones require fatty acids to create fuel, so in a ketogenic diet you can structure the diet in such a way to have a diet full of fats and also use existing body fats as fuel, a process known as nutritional ketosis (see the article ‘Ketosis: Metabolic Flexibility in Action’).
This is the alternative way proposed in a Low Carb High Fat diet. When glucose levels are low, especially over time, most cells will switch to using ketone bodies for fuel. Because glucose is restricted on a low carb and high fat Banting diet to below 25g per day, blood sugars naturally fall and insulin levels also naturally fall.
The higher fats are required for energy. Over time, ketones are able to energize cellular mitochondria which in the past could not get sufficient energy due to insulin resistance on a high carb diet. The likely result of burning ketones is increased overall energy often reported by Banters (those following a low carb high fat lifestyle).
In addition, the unique properties of ketones make them a ‘cleaner’ fuel: ‘Burning fat for fuel causes less oxidative damage (think “free radicals”) to the cell, and actually makes it possible for the cell to create much more energy than it can from glucose’ (‘Ketosis: Metabolic Flexibility in Action’).
The remaining problem is that Insulin Resistance is not cured, it is simply bypassed. If you return to a Low Fat High Carbohydrate diet the Insulin Resistance pathway in the cell remains. However if you lose significant weight on a ketogenic diet and return to a normal BMI, the effect of Insulin Resistance diminishes.
To remain free of Insulin Resistance, a Low Carb and High Fat Banting-style, ketogenic diet must become a lifestyle.
De Luca, Carl & Olefsky, Jerrold M. (2008). Inflammation and insulin resistance, FEBS Letters, 582, 1, 97-105). http://www.sciencedirect.com/science/article/pii/S0014579307012082, accessed 20 Nov 2015.
Journey into Nutritional Ketosis (no date). ‘What is nutritional ketosis’, http://nutritionalketosisforhealth.com/what-is-nutritional-ketosis/, accessed 15 Nov 2015.
Ketogenic Diet Resource (no date). ‘Ketosis: Metabolic Flexibility in Action’, http://www.ketogenic-diet-resource.com/ketosis.html, accessed 15 Nov 2015.
Ketogenic Diet Resource (no date). ‘Metabolic syndrome’, http://www.ketogenic-diet-resource.com/metabolic-syndrome.html accessed 15 Nov 2015.
Nutrition Facts (29 Jan 2015). ‘What causes insulin resistance’, https://vimeo.com/118193797, accessed 15 Nov 2015.