Chronic kidney disease, high-content vegetables and fruits are eaten to prevent it.

Studies have shown that patients with chronic kidney disease consume enough dietary fiber and vegetable protein to help maintain their health, such as reducing mortality.

Researchers from Severance Hospital’s Family Medicine Professor Lee Ji-won, Yongin Severance Hospital’s Family Medicine Professor Kwon Kwon-jin, and Gangnam Severance Hospital’s Medical Statistics Professor Lee Hye-sun said on the 18th that the higher the dietary fiber intake, the lower the risk of death.

Diet guidelines for patients with chronic kidney disease at home and abroad suggest a very limited diet to prevent kidney function from deteriorating. Representatively, it warns of the intake of potassium and protein, and as a result, there has been a misunderstanding about the intake of vegetable proteins such as vegetables, fruits, and whole grains containing not only potassium but also dietary fiber.

The research team used data from 3,892 patients with chronic kidney disease aged 40 to 68 during the Korea Genome Mechanics Survey by the Korea Centers for Disease Control and Prevention to find out the effect of dietary fiber and plant protein intake on mortality in patients with chronic kidney disease.

◇ Dietary fiber consumption lowers mortality by up to 44%

The research team divided the entire patient group into five groups according to the degree of dietary fiber intake in order to investigate the mortality rate according to the degree of dietary fiber intake of patients with chronic kidney disease. Dietary fiber intake in each group was 0.5~3.01g, 3.02~4.15g, 4.16~5.26g, 5.27~6.76g, and 6.77~27.6g per day. The average of all patients was 5.1g, far behind the recommended dietary fiber intake of 25g for men and 20g for women in Korea.

Next, as a result of confirming the case of actual death during the follow-up period of 10.1 years, the mortality rate decreased as the dietary fiber was consumed more. In the group that consumed the most fiber, the total mortality rate was 37% lower than that of the group that consumed the least, and the probability of dying from cardiovascular disease fell to 44%.

The annual deaths per 1,000 patients were 9.6, 12.8, 12.7, 15.7, and 23.5, respectively, in the order of high dietary fiber intake, and 2.2, 2.5, 3.3, 2.9, and 6.6 patients died of cardiovascular disease.

Patients with chronic kidney disease should limit their potassium-rich intake of tomatoes, kiwis, and melons, and eat apples, tangerines, grapes, pineapples, and plums. Also, try to eat fresh fruits rather than dried ones. In the case of vegetables, cut vegetables into small pieces in a thin slice, except for the skin and stem, which are high in potassium, and soak them in sufficient water before cooking. It is also good to blanch it in boiling water and rinse it several times.

◇ Protein intake, unrelated to mortality

In the same way as the research team’s dietary fiber intake survey, the patient group was divided into five groups according to the daily protein intake. There was no significant difference in mortality between the group that consumed the least protein per day (0.179 to 0.546 g/kg) and the group that consumed the most (1.041 to 3.573 g/kg).

As a result of confirming the cases of actual death during the follow-up period of 11.1 years, the annual deaths per 1,000 patients were 19.3, 14.6, 13.8, 14.4, and 11.5, respectively, in the order of eating less protein. Excluding the effects of gender, age, body mass index, smoking and drinking, total daily calorie intake, and chronic disease, the increase in protein intake was unrelated to mortality.

The research team found the reason why there is no difference in mortality due to protein intake in the types of proteins that Koreans usually consume. Protein intake guidelines for patients with chronic kidney disease are based on Westerners who consume protein mainly from animal proteins such as pork, beef, and milk. However, the results are different from the existing guidelines, with 63.07% of all protein consumed by Koreans, mainly vegetables, grains, and nuts, and fish.

Through the results of this study, it is expected that it will be possible to recommend patients with chronic kidney disease to reduce animal proteins rather than avoid protein itself, but to consume vegetable proteins such as vegetables, fruits, nuts, and beans steadily.

Professor Lee Ji-won said, “Fibre can help induce uremic excretion by increasing feces and reduce chronic inflammation,” adding, “Education on healthy dietary fiber intake is important for patients with chronic kidney disease.”

Professor Kwon Kwon said, “It is better for patients with chronic kidney disease to eat plant proteins than to reduce protein intake,” adding, “If protein intake decreases, carbohydrate intake can increase and diabetes can worsen, so we recommend eating plant proteins through beans, whole grains, and nuts in addition to red meat.”

The results of this study were published in the latest issue of Frontiers in Nutrition, an international journal in food science, and were supported by the Ministry of Trade, Industry and Energy’s “user-participating big data-based health risk prediction and management service” and the Agriculture, Food and Rural Affairs Institute.