Do weight-losing diets harm the functionality of the kidneys?

Obesity is commonly associated with a high risk of several chronic disorders including diabetes mellitus, cancer, and cardiovascular diseases. However, studies have also reported that weight loss could be associated with the incidence of CKD (chronic kidney disease) even in healthy individuals, especially males.

The weight-losing diets have been found to produce an adverse impact on the functions of the kidneys putting patients at a risk of renal diseases.

Hence, there is a need to investigate the effect of weight-loss diets on the kidney functions.

Kidney and its Function

Kidneys are among the vital organs of the human body that help to flush out toxic waste products and harmful chemicalsfrom the system and maintain the balance of fluids, water, minerals, and electrolytes including sodium and potassium. 

Kidneys also help in the production of urine and purify the blood by supporting the removal of waste and other unwanted chemicals from the body.

Other than excreting the excess of water, toxic waste, and the by-products of metabolism, kidneys also play a key role in maintaining the health of the bones and the production of hemoglobin.

The kidneys are made of millions of nephrons that have a limited capacity to repair and regenerate. The tubular cells are the only parts of the nephrons that have the ability to regenerate after damage. The other cells comprising the nephrons cannot regenerate.

Hence, the damage to these cells could be permanent. This is why; it is important to be aware of the impact of a weight loss diet on the kidney functions in order to protect these vital organs against severe permanent damage.

Carbohydrate restriction with a high-protein diet for a prolonged period is usually not suitable for patients with chronic kidney disease as this form of diet may cause further damage to the kidneys. 

You can attend our AARC Approved CEUs to learn more about how a high-protein diet aimed at weight loss could cause damage to the kidneys and affect the functioning of these organs.

Weight loss diet and kidney functioning

Losing weight is very difficult. However, it can become more complicated, when the patient chooses a high-protein diet that aids weight loss primarily by making the stomach full.

The high-protein diets are usually safe and do not produce an adverse impact on kidney functioning when followed for a few weeks. However, following a high-protein diet for a longer period, especially with carbohydrate restriction, may affect the kidney functions by causing kidney damage.

Patients with chronic kidney disease are usually advised to consume about 0.6 - 0.75 grams of protein per kg body weight per day. Following a high protein diet for weight loss usually involves the intake of up to 1.9 grams of protein per kg body weight per day.

This is significantly higher than the amounts typically recommended for kidney patients. The higher intake of protein can cause further damage to the kidneys and accelerate the disease progression.

The effect of weight loss diets on kidney functions

The kidneys have unique functions and structures. A high-protein weight-loss diet could lead to kidney failure due to which the patient may develop serious complications with a high risk of mortality.

Other weight-loss diets like the keto diet and Atkins diets have also received a lot of attention for the adverse impact they produce on the renal functions. These diets typically recommend eating a higher amount of fats with a moderate to high amount of protein and a low amount of carbohydrates.

These diets can interfere with the normal functioning of the kidneys and other organs due to which patients may develop renal failure and other compilations.

The long-term impact of weight-loss diets on the kidneys

A high-protein diet followed for an extended period of time could worsen kidney function severely. Some high-protein diets also restrict the intake of carbohydrates, which makes it even more difficult for the body to eliminate the waste products released during protein metabolism.

Obese people on a weight loss diet often consume a high amount of protein with a minimal amount of carbohydrates. This form of a diet carries an inherent risk of renal damage because the human body is designed to use carbohydrates as its immediate source of energy. Fats are used by our body as a storage form of fuel, while proteins are considered the last option for the source of fuel.

It is easier and simpler for the body to generate energy from the breakdown of carbohydrates. However, the body needs to modify and activate several other metabolic pathways in order to generate an adequate amount of energy from proteins and fats. So, proteins and fats are not just inherently inefficient sources of fuel but also create more strain on the vital organs when used to produce energy.

Consuming a diet that has a disproportionately high amount of proteins and fats definitely helps people lose weight.  However, the high intake of proteins, together with a low intake of carbohydrates, also results in the generation of a large amount of acid load and nitrogenous waste, which requires the kidneys to work harder to excrete them.

This can result in the hyperfiltration injury to the kidneys, eventually leading to renal failure.

Our respiratory conference for nurses is aimed at providing detailed information about how different diets affect the kidney functions and the safer way to lose weight.

Conclusion

For obese patients, it is essential to follow a diet that is naturally balanced and low in calories. A diet comprising fresh fruits and vegetables, low-fat dairy products, whole grains, fish, beans, poultry, and nuts could be safe and effective for promoting weight loss. 

It is important to recognize the impact of weight-loss diets on the kidney functions and adopt safer ways to lose weight in order to reduce the risk of renal failure. Doctors and other healthcare professionals can attend our Respiratory Disease & Care Conference to get a deeper understanding of the effects of weight-loss diets on the kidneys to be able to provide the most appropriate advice to their patients.