Glycolysis vs Ketosis

As much as I don’t plan on this being a food or keto blog, the next few posts will probably be about keto and… well, food.  Weight loss is a huge part of my Fit for 40 plan, so it’s on my mind a lot lately, and I tend to write about what’s interesting to me in the moment.  And right now, I’m focused on my diet.  I swear I have other posts planned, but I wanted to get these out of the way first.

I’ve mentioned Keto in a couple posts, and wanted to do a few more posts on glycolysis vs ketosis (regular U.S. diet vs keto), exactly what keto is, how to start it, and some pros and cons of the diet.  First, I am not a doctor, and you should always consult yours before starting a new diet or exercise routine.

The ketogenic diet (Keto) is a low carbohydrate, high fat, moderate protein (LCHF) diet. Most people do keto to help in weight loss; but, it also has other health advantages like: lowering risk for heart disease, diabetes, cancer, stroke, migraines, depression, helping those with epilepsy and other neurological illnesses, and much more.1

Keto is meant to put your body into a state of ketosis, where you burn ketones for fuel (Ketosis) instead of glucose (Glycolysis).

Boring explanation of how carbs work in your body.

When you eat food with carbs your body produces glucose and insulin.  Carbs are broken down into glucose, a single molecule of sugar that your body uses for energy.  Glucose is the simplest molecule your body can use to convert and use as energy, so it will be chosen first over any other energy source.2


However, sugar needs help getting into your cells. When your body creates glucose from carbs, your pancreas produces insulin, a hormone that tells your body to burn the sugar first and to stop burning fat.  Insulin gets released into your bloodstream, and then attaches itself to your cells signaling them to absorb the sugar from your bloodstream.

If you have more sugar in your body than needed (because you scarfed a donut), insulin directs your body to store the sugar in your liver.  It then releases it when your blood sugar is low, or if you need more sugar, like for physical activity.  As blood sugar levels rise, the pancreas releases more insulin.3

It sounds like everything works the way it should then, right?!  How does that donut end up on your hips?  Well, your cells only store what they need. Any glucose the cell doesn’t require is converted to glycogen and stored in your liver and muscles.  After that, any glycogen left over is then converted to fat, known as lipogenesis.4

By the way, I use donuts as an example, but carbs can be found in a lot of foods.  From sweets, breads, pastas, and juice, to meats and other proteins, and most fruits and vegetables.  When I discuss Keto it will be with a focus on eliminating high carb foods.  Lower carb foods are still completely doable and okay to eat.  No worries that I’m endorsing unhealthy eating!  In fact, my family is now eating more vegetables than we ever have before!

Are you still reading?  Still awake?  Oh good!  Let me try to put you to sleep with an equally boring explanation of how ketones work in the body!

Boring explanation of how Ketones work in your body.

You actually enter into some form of ketosis every day, typically at night when you’re sleeping.  Your body enters into ketosis when it has no more glucose or glycogen from carbs for processing.  Your body starts looking for another energy source, and for that, it starts to produce ketones by breaking down fats.  The fats are turned into fatty acids which are used in the liver, known as beta-oxidation.  This produces ketones, which then gives your body the energy to fuel your muscles and brain.  So your new energy sources is fats instead of carbs, which is why it’s so important to make sure if you try a low carb diet, that you have adequate amounts of fat included.5

glycolysis vs ketosis
Eating low carb gives you a lower, more steady, blood glucose (from protein and low carb veggies), resulting in lower amounts of insulin. This increases the release of fat from your fat stores and increases fat burning. This usually leads to greater fat loss, especially around the belly.

An LCHF diet makes it easier for the body to use its fat reserves, as their release is no longer blocked by high insulin levels. This may be one reason why eating fat produces a feeling of longer-lasting satiety than carbohydrates.7

how ketosis works

Beyond the science.

So, having said all that (You did read all that didn’t you?), I want to stress that just as with any diet, it takes real effort; and, though it’s cliché, it does take a lifestyle change in order to sustain the weight loss and not regain all the weight back.

Some of you may be worried about the words high fat.  For years we’ve been told by the government and nutritionists that fat is bad for you.  Cut fat.  Eliminate fat.  Lower fat intake.

And what happened?  Obesity rates in the U.S. went up!  At exponential rates!  Since the 1960s obesity rates have doubled!8   Now this is probably a mix of things: an increase in sugar and carb filled products, more processed products, increased availability of fast food, and we can probably also add technological improvements that lead to more sit down jobs.

So I’m not saying that rising obesity rates happened from the war on fat alone.  However, an increasing amount of information has been coming out the in last decade that proves that eating more fat improves satiety (meaning you’ll naturally eat less and go longer between meals), improves HDL (good cholesterol), doesn’t affect LDL (bad cholesterol), and lowers blood pressure.  And honestly, higher fat just means higher in fat in comparison to carbs and protein based off percentages.  It’s almost like the food pyramid in reverse.  It doesn’t mean you have to down a stick of butter with every meal (in fact, I’m just going to go ahead and advise against that), so please don’t be afraid of the word fat!  At least, not in relation to your food.

low carb high fat diet

Of all the low carb diets out there, I decided to go with Keto because it advocates not increasing carbs too much after the adaptation phase.  I have a history of carbs and sugar increasing my hunger for more… and more… and more(!) food.  I feel it’s better to stick with as low of a carb intake as I can do, while still eating healthy.

If you are interested in joining me on my journey, check back in for my next post!  I will go into more details on what Keto is, how to eat the Keto way, and the pros and cons of following the diet.

Thanks for sticking with me this far!

Please don’t mind the mess.

Jessica Signature2


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