Protein & Keto - Are you getting enough??

Protein & Keto - Are you getting enough??


There is a widely-circulated claim that excess protein is detrimental to ketosis because it causes gluconeogenesis.

This myth has since been disproven. However, there are plenty of articles published online stating this false claim, so lets explain how GNG really works on ketosis.

Gluconeogenesis (GNG) is a metabolic pathway that allows your liver and kidneys to make glucose from non-carbohydrate sources.

The word gluconeogenesis has three parts to it:

  • Gluco — coming from the greek root glukos – literally meaning “sweet wine.”
  • Neo — “new”
  • Genesis — “creation”

So a great way to think about it is this is how your body creates new sweet wine for your body. This process is special because it’s the creation of glucose from anything but carbs.

Your body takes compounds like lactate, amino acids (protein), and glycerol to manufacture glucose when there are no carbs around.

This may seem like a problem when you’re trying to run on ketones instead of glucose,  but the truth is gluconeogenesis has an incredibly important purpose — and no, it doesn’t harm ketosis.

Some people tout that “you don’t need carbohydrates to survive,” which is only partially true.

To clarify, you don’t need to eat any high carb foods to survive, but make no mistake — your body needs glucose and glycogen to keep you healthy (even on ketosis) and it will get this via survival mechanisms like gluconeogenesis.


On a keto diet, your body uses gluconeogenesis for 3 main purposes:

  • Preventing hypoglycemia.Your glucose levels can never drop to zero, even on ketosis. GNG keeps your blood sugar on a healthy range so it doesn’t fall to dangerous levels (aka hypoglycemia).
  • Fueling tissues that can’t use ketones. There are a handful of cells in your body that can only use glucose to survive, including red blood cells, kidney medulla (inner part of the kidney), testicles and some parts of your brain. Ketones can cover up to 70% of your brain’s energy needs while glucose from GNG covers the rest. The other organs can’t metabolize ketones at all, so gluconeogenesis provides them with enough glucose to remain healthy.
  • Resupplying glycogen stores. You can actually replenish muscle glycogen through the GNG that happens during ketosis — at least if you’re not a professional athlete or participate in competitions. Glycogen is crucial for muscle recovery after workouts.

These functions are incredibly important. If GNG didn’t make enough glucose to cover them, your body could never make the switch to using ketones for energy because some cells (like red blood cells) would die and your blood sugar would drop too low.

This means gluconeogenesis makes ketosis possible.


Now, could you boost the rate GNG if you eat too much protein? Not likely.

GNG is an extremely stable process. It’s not easy to increase it even with extra protein.

Gluconeogenesis (making glucose from non-carbs) doesn’t work at the same rate as carbohydrate metabolism (making glucose from carbs).

When you eat chocolate cake, your blood glucose quickly spikes in response to that sugar.

When you eat extra protein, your blood glucose doesn’t spike the same way. Studies have shown that GNG production doesn’t increase even with extra amino acids.

By now we have made a few things clear:

  • Gluconeogenesis is the process of making internal glucose from non-carb sources, including protein
  • Gluconeogenesis is necessary for survival
  • Gluconeogenesis makes ketosis possible
  • Eating too much protein won’t increase the rate of gluconeogenesis

But eating protein isn’t just safe, it’s necessary.

3 Reasons Why You Should Eat More Protein On Keto

Here’s why eating adequate amounts of protein is beneficial on the ketogenic diet:


Most people on keto will limit their protein to 30-40 grams, limit their carbs to 10-20 grams, then eat an excessive amount of fat. This is a common mistake.

If your goal is to lose fat, increased protein consumption is a great way to approach your ketogenic diet plan. Here’s why

  • Protein is more satiating than fat
  • Protein is more nutrient dense
  • People tend to overeat when protein is low

Additionally, the most effective way to start losing weight on keto is to burn your stored body fat for energy, not the new dietary fat you’re eating.

If you eat too much fat, your body will burn that new fat coming in and won’t get the chance to burn your stored fat reserves.

You can overcome weight loss plateaus by increasing protein and lowering your fat consumption.


Your body needs to use more energy (calories) to burn protein than to burn to fat.

For example, when you eat a 100-calorie serving of grass fed beef, your body can only store 75% of it as calories because it requires 25% of calories to burn it and use it as fuel. Conversely, when you consume fat, you are storing up to 98% of it as calories.

This means you’re storing almost all of the calories from fat, whereas you’ll store less from protein since you use up some of the calories to burn it.


Not eating enough protein on keto has serious side effects, including:

  • Worsened workout performance: Without enough protein, you won’t be able to maintain muscle mass, let alone build muscle.
  • Neuron atrophy: Your brain needs amino acids to function optimally. Research finds a protein-deficient diet can lead to atrophy and neuron loss.
  • Weaker immune system: A deficiency in the amino acid arginine can contribute to the dysfunction of your T cells — the cells that regulate your immunity.
  • Increased risk of diseases: A deficiency in amino acids can increase the risk of developing certain diseases, including: sickle cell disease, acute asthma, cystic fibrosis, pulmonary hypertension, cardiovascular disease and certain cancers.

In fact, a lot of these keto side effects happen due to eating too little protein.

  • Thyroid problems
  • Weight loss plateaus
  • Hormonal problems
  • Hair loss

Now that you know why protein matters, it’s important to choose the best possible protein sources for your diet.

Choosing the Best Keto Protein Sources

When selecting keto protein sources, choose the highest quality you can reasonably afford.


These are the best sources of protein on the keto diet:

  • Beef, preferably fattier cuts like steak, veal, roast, ground beef and stews
  • Poultry, including chicken breasts, quail, duck, turkey and wild game — try to focus on the darker, fattier meats
  • Pork, including pork loin, tenderloin, chops, ham, bacon and ground
  • Fish, including mackerel, tuna, salmon, trout, halibut, cod, catfish and mahi-mahi
  • Shellfish, including oysters, clams, crab, mussels and lobster
  • Organ meats, including heart, liver, tongue, kidney and offal
  • Eggs, including deviled, fried, scrambled and boiled — use the whole egg
  • Lamb meat
  • Goat meat
  • Grass fed, full-fat dairy, including grass fed butter, heavy cream, cottage cheese and cream cheese
  • Vegetarian sources, like macadamia nuts, almonds and nut butter


Collagen is a type of protein — the most abundant protein found in your body.

It’s considered the glue that holds your body together, making up the tissue in cartilage, muscles, joints, skin, hair, eyes, heart, gut, brain, and nails, and it’s credited with a wide range of health benefits, including:

  • Better skin health
  • Hair loss prevention
  • Muscle growth and regeneration
  • Maintaining the integrity of tendons, ligaments and cartilage
  • Strengthening your bones and preventing osteoporosis
  • Repairing tissues (forming scars)
  • Maintaining proper vision
  • Preventing leaky gut
  • Helping your heart beat
  • Ensuring optimal brain function

Source - Excerpt from by Dr Anthony Gustin