Keto And Kidney Health: What's The Real Risk?

The ketogenic diet is a popular weight-loss strategy that involves eating a high-fat, low-carbohydrate diet. While it can be effective for weight loss, there are concerns about its potential impact on kidney health. The diet is associated with an increased risk of kidney stones and may worsen metabolic acidosis, affecting bone and muscle health. People with kidney disease are advised to avoid the keto diet as it may further decline their kidney function. However, a recent clinical trial found that the keto diet improved kidney function in patients with polycystic kidney disease.

Keto can lead to kidney stones

The ketogenic diet is a high-fat, low-carb approach to eating that has become one of the most popular ways to lose weight. However, it is important to be aware of the risks before giving it a go. One of the potential dangers of the keto diet is that it can put stress on the kidneys and may lead to kidney stones.

Kidney stones are a well-documented potential side effect of the ketogenic diet. Research has shown that among children following the keto diet as a treatment for epilepsy, 13 out of 195 subjects developed kidney stones. The formation of kidney stones is due to several factors, including chronic acidosis, dehydration, low urine pH, and fat malabsorption, all of which can be caused by the keto diet. Chronic acidosis, in particular, can decrease calcium reabsorption in the renal tubules, leading to increased urinary calcium excretion and increased risk of kidney stone formation.

The risk of kidney stones on the keto diet can be mitigated by increasing fluid intake and making the urine more alkaline. Oral potassium citrate supplementation has been shown to be effective in preventing kidney stone formation in children on the keto diet. Additionally, a diet rich in plant-based proteins instead of animal proteins may also reduce the risk of kidney stones, as animal proteins increase the acidity of urine.

It is important to consult with a healthcare practitioner before starting the keto diet, especially for those with kidney disease, as the diet may need to be individualized to avoid adverse effects.

It may worsen metabolic acidosis

The keto diet can potentially worsen metabolic acidosis, a common complication of chronic kidney disease, which ultimately affects bone and muscle health. Metabolic acidosis is a condition in which there is an excessive amount of acid in the body fluids. It can be caused by the overproduction of ketone bodies, which occurs when carbohydrates are completely removed from the diet.

The keto diet is a high-fat, adequate-protein, and low-carbohydrate diet. When the body doesn't have enough carbohydrates to use as energy, it starts breaking down fat for fuel, producing ketones in the process. While this can lead to a state of ketosis, which is the goal of the keto diet, it can also result in an overproduction of ketones, causing ketoacidosis. Ketoacidosis is a dangerous condition that can lead to a significant increase in the acidity of the blood.

The increased acid production from a ketogenic diet can cause metabolic acidosis and related issues, including weakened bone health. Studies have shown that people with chronic kidney disease and those without prior kidney problems are experiencing a decline in kidney function due to the keto diet. High intake of animal proteins, which is common on the keto diet, can make the urine more acidic and increase the risk of kidney stones.

Additionally, the keto diet can be dangerous for people with kidney disease as they often need to follow a low-protein diet, which may not align with the keto diet. The keto diet can also lead to an increased risk of gout, which is a type of arthritis, due to the high levels of uric acid produced.

It is important to note that the effects of the keto diet on kidney function may be influenced by the source of dietary protein. Studies have shown that animal protein has a higher incidence of kidney injury compared to plant-based protein. Therefore, it is crucial to consult a healthcare professional before starting the keto diet, especially for individuals with kidney disease or those at risk of developing it.

It may increase the risk of gout

The keto diet may increase the risk of gout, a form of inflammatory arthritis that affects 4% of American adults. Gout occurs when there is too much uric acid in the blood, which can lead to needle-like crystals forming in the joints, causing pain, tenderness, swelling, and redness.

The keto diet is high in purine-rich foods, and purines are broken down by the body into uric acid. When entering ketosis, there is a short-term increase in the risk of gout flares due to the competitive inhibition of ketones on the kidney's excretion of uric acid. However, once the body adapts to ketosis, the long-term risk of gout decreases.

Research has shown that a well-formulated ketogenic diet may have potent anti-inflammatory properties, and can be protective against joint damage caused by gout. A 2017 study by Yale researchers found that the primary ketone in our blood, beta-hydroxybutyrate (BOHB), can reduce damaging inflammation without reducing the benefits of inflammation, such as healing and our body's defences against infection.

However, it is important to note that the keto diet is not recommended as a treatment for gout, as more studies are needed to understand the relationship between the two. Additionally, the keto diet is not suitable for everyone, and it is always best to consult with a doctor or healthcare professional before making any drastic changes to your diet.

It can be dangerous for people with kidney disease

The ketogenic diet can be dangerous for people with kidney disease. This is because the keto diet is high in animal protein and fat, which can increase the risk of kidney stones and other complications. People with kidney disease often need to follow a low-protein diet, which may not align with the keto diet.

The keto diet can lead to an increased risk of kidney stones as it raises the levels of acid in the blood. This is known as acidosis, which can also cause a decline in kidney function for those who already have chronic kidney disease. When following a high-protein diet, the kidney must work harder, leading to the progression of chronic kidney disease.

The keto diet can also worsen metabolic acidosis, a common complication of chronic kidney disease, which can affect bone and muscle health. High protein intake has been linked to an increase in kidney volume and weight, resulting in the expansion of the mesangial matrix and tubulointerstitial fibrosis. This can lead to proteinuria and a loss of kidney function.

People with kidney disease should consult with their doctor before starting any new diet, including the keto diet. Alternative diets, such as the Mediterranean or plant-dominant diet, may be safer options for those with kidney disease.

It may lead to high cholesterol

The ketogenic diet is a high-fat, low-carb approach to losing weight. It involves eating up to 80% of your calories from fat and sticking with 20 to 50 grams of net carbs a day. This means that you will be eating a lot of fat, and to meet this quota, you may end up including unhealthy choices such as butter, coconut oil, and animal fat. These are all sources of saturated fat, which has been linked to poor heart health by the American Heart Association (AHA).

The keto diet may lead to high cholesterol, which in turn may increase your risk of heart disease. Research has shown that the keto diet produces modest reductions in triglycerides, modest changes in heart-protective high-density lipoprotein (HDL, or "good" cholesterol), and minimal changes in low-density lipoprotein (LDL, or "bad" cholesterol). However, some studies have shown an increase in LDL on low- or very-low-carb diets.

The impact of the keto diet on cholesterol levels depends on the quality of the diet. If the diet is high in healthy unsaturated fat and limited in unhealthy saturated fat, it can lead to a decrease in LDL. On the other hand, if the diet includes a lot of saturated fat, it is likely to increase LDL levels.

In addition, people with a genetic mutation that affects the way LDL particles are regulated may experience a significant increase in LDL levels if they follow a keto diet. This is a long-recognized phenomenon, and while it doesn't happen often, it can be dangerous for those individuals.

Therefore, while the keto diet may not be inherently harmful to everyone, it is important to be aware of the potential risks and take steps to follow a heart-healthy version of the diet if you choose to try it. This includes choosing heart-healthy, unsaturated fats and maximizing the small amount of carbohydrates allowed by including low-GI-index veggies.

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