I’m sure by now you have heard all about the ketogenic diet – or “keto” for short. You may have a friend or family member that has sworn by the weight loss they’ve experienced following this diet. Maybe you’ve even looked into what a keto meal plan looks like. But if you have a health condition, like kidney disease, you need to think twice before jumping on this overcrowded bandwagon.
What is the ketogenic or “keto” diet?
Historically, the ketogenic diet is a medically-prescribed diet to help those with epilepsy control. The diet is tightly regulated by dietitians and monitored by a medical team in a hospital or other in-patient setting.
The ketogenic diet gets it’s name from the effect of turning the body to ketosis to create energy.
This happens when adequate carbohydrate sources are gone and the body is looking for a new source of energy.
Ketone bodies are created in the liver from the breakdown of triglycerides to fatty acids and ketones to be used as energy for the body.
In order for a person to be in a state of ketosis, the diet focuses on a high-fat, very-low-carbohydrate diet to supply the energy needs to the body via fatty acids rather than glucose or carbohydrates.
Macronutrients in the ketogenic diet are;
70-80% from fat
10-20% from protein
5-10% from carbohydrates
There can be some flexibility on the percentages of protein and fat, but rarely carbohydrates.
The carbohydrate intake per day should remain below 20 grams. (1)
The main difference between diets like the ketogenic diet and Atkins or Zone is that the ketogenic diet focuses on the main source of energy as fats rather than protein.
With only 5% of your energy needs coming from carbohydrates, that could look like just an apple (which has approximately 15 grams of carbohydrates) for the day! No bread, no rice, no pasta, no fruit, very few vegetables in small portions.
Foods allowed on the ketogenic diet
This is a high-fat diet, not a high-protein diet.
Therefore, the bulk of foods recommended are things like;
high-fat nuts and seeds
heavy whipping cream
Most people who say they follow a ketogenic diet are likely not in true ketosis. That requires at least 3 days but up to weeks of following a strict diet just to use up the glucose stores and enter the process of ketogenesis.
This means there can be no such thing as a “cheat day” on a true ketogenic diet. The diet they are following is likely more of a low-carb, moderate to high-protein and/or high fat diet.
The brain uses carbohydrates as it’s number one source of energy.
Think of your brain as the Ferrari of cars. It needs the best fuel to work its best. Give it the lowest-grade gasoline and you won’t get the best use of the engine you expect out of a top-rated vehicle.
Your red blood cells rely on carbohydrates for it’s energy.
This can also be why people experience lethargy and weakness when starting the keto diet.
Some of the benefits of the keto diet that are claimed, but need to be researched further in long-term studies, include;
blood sugar control for type 2 diabetes (2)
blood pressure control
And other disorders (3)
“But my sister’s friend’s brother has done keto and lost 25 pounds!”
Okay, sure. The logic is there for a person to lose weight in the beginning of a ketogenic diet.
This is because the body is deprived of our number one fuel source – carbohydrates – for long enough that the carbohydrates stored in the body have been used up for energy.
When carbohydrates are used for energy, water is also released from the body. Ever heard of the water-weight concept for immediate and large weight loss? Well, that’s why it happens.
Not only that, but by creating such a restrictive diet, it is possibly the total number of calories in is lower to result in weight loss anyway. (4)
Similar to the “cabbage diet” or other diets that only let you eat certain things – you will get tired of it and you will end up eating less. Or “sabotaging” your diet and eating other foods, causing guilt, weight cycling, and of course the diet cycling.
Is keto bad for your liver and kidneys?
Blood Pressure Swings
Many people with kidney disease have blood pressure issues as hypertension is one of the top causes of kidney disease.
This is caused by the shift of sodium leaving the body, leading to drops in blood pressure. (5)
With the severe change in diet, low blood pressure drops can occur. This can result in weakness, lethargy, headaches, and dizziness.
Blood Sugars and Insulin
The second top cause of kidney disease is diabetes, which means many people with kidney disease may require insulin.
The ketogenic diet shifts the liver’s primary role of insulin regulation with ketone generation. This means insulin levels produced can change drastically.
If you are already requiring insulin, whether it’s for type 1 or type 2 diabetes, you absolutely need to speak with your doctor and dietitian before trying a ketogenic diet.
There is a risk of falling into ketoacidosis – a serious health complication. The keto diet is generally not recommended for anyone with type 1 diabetes due to the need for tight insulin control.
As the diet focuses on high-fat foods and severely restricts the intake of carbohydrate foods, such as fruits, vegetables, legumes, and dairy, it puts you at risk for nutritional deficiencies.
These deficiencies can include B vitamins (often found in fortified whole grains and produce), calcium (found in dairy and dark greens), vitamin D, and potassium.
Those following a ketogenic diet are then required to supplement their diet (because the food that provide these nutrients are forbidden) to ensure these deficiencies do not lead to further health complications.
The ketogenic diet may increase the risk of kidney stones.
As the diet focuses on high-fat foods, there is a severe increase in the intake of saturated fats.
This can lead to an increase in unhealthy cholesterol and LDL levels in the blood, but some studies have also found that it may actually decrease the unhealthy fat levels in the body. (6)
Regardless, the diet has not been studied enough yet to have any conclusive results in this matter.
Other potential side effects on keto
People often experience constipation on the ketogenic diet. This is due to the fact that carbohydrates, and therefore fiber, are not allowed on the diet.
Additionally, as the diet limits intakes of fruits and most vegetables, a shift may be seen in the acidity of the blood. The kidneys will work to correct the pH balance (it’s one of the many things they take care of), but it still creates an imbalance due to the imbalanced diet.
Doesn’t sound like the body is too happy with the effects, huh?
What about the keto diet and chronic kidney disease?
Due to the potential side effects and risks of the ketogenic diet, I do not typically recommend it for those with kidney disease. There have been no long-term studies on the kidney disease population with the ketogenic diet, which may say something to the lack of evidence or even the risk involved in assessing the diet on those with CKD.
In January 2020, a 3-month study came out of Italy to test the use of a very low calorie ketogenic diet on obese individuals with “mild kidney failure.” But in closer look at the study, they only used individuals with a GFR (glomerular filtration rate) of at least 60 mL/min/1.73m2. So those with stage 3 kidney disease or beyond were not allowed to participate in this study. (7)
The number of individuals with GFR between 60-89 was only 38 people, making this a very small study. Initial labs of those with declined kidney function still reflected creatinine, BUN, phosphorus, potassium and A1c levels within normal range.
The diet was strictly followed by physicians and dietitians, tested daily with keto test strips to ensure ketosis was ongoing.
And in the results, “VLCKD [very low calorie ketogenic diet] is therefore a safe and effective dietary intervention in patients with obesity affected by mild CKD [chronic kidney disease] when conducted under medical supervision in a real‐life setting, although caution should be taken in screening for a lack of micronutrients and for altered bone metabolism, as well as in accurately monitoring protein consumption at all times.”
Why are you interested in the ketogenic diet in the first place? Are you looking to lose weight? To better control your blood pressure or blood sugars? Do you want to keep your kidney’s healthy?
I highly encourage you to work with a dietitian to find the best plan that works for you without risking negative effects on a diet that is not proven to help people who have kidney disease.
If you want to follow a ketogenic diet for kidney disease, work with a renal dietitian.
Even in the study, it is clear that working closely with medical professionals is essential in success for weight loss.
When determining the best diet for you, think about the long game.
Could you follow a keto diet for life?? Never enjoy a piece of pre-dinner bread again? Decline every bowl of creamy, decadent pasta in your future?
If you can wholeheartedly say yes, then you should talk with your doctor and dietitian about how to start! You definitely should work with a renal dietitian as the need for high-fat and low-carb is essential while monitoring renal function for ongoing success.
If your main goal- as is many others – is to lose weight, there are plenty of other healthier, proven methods to result in some beneficial weight loss.
We can work together with coaching and customized meal plans that are meant to help you safely lose weight, control blood sugars, or get rid of hypertension for the long-term.
Don’t know what’s best for you? Ask me!
Disclaimer: This information is not intended to replace any medical treatment or information provided by your health care team. Please consult with your doctor and health care team before starting or changing any diet, medicinal, or supplement protocols.