Can I eat soy products if I have kidney disease?

Author: Chen Zhou, Department of Nephrology, Shanghai Changhai Hospital

Reviewer: Mei Xiaobin, Chief Physician, Nephrology Department, Shanghai Changhai Hospital

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Have you ever heard such a statement, "Kidney disease patients cannot eat soy products, because soy products contain high-purine plant protein, which will increase the burden on the kidneys, leading to increased uric acid and gout attacks". If you believe this statement, then you have missed a very healthy and delicious food - soybeans. As a nephrologist, I can say responsibly: "Soy products can be eaten by chronic kidney disease patients and are recommended! Why? Please follow me to unveil the mystery of soybeans!"

1. Some common sense about soybeans

First of all, we need to clarify what soybeans are. The soybeans here only refer to soybeans, green beans, and black beans, and do not include other beans such as red beans, mung beans, and kidney beans. Soybeans are a very ancient crop that originated in China and are widely planted and used all over the world. Soybeans can not only be eaten directly, but also processed into various soy products, such as tofu, soy milk, tofu skin, oil residue, vegetarian chicken, vegetarian goose, vegetarian duck, etc. Soybeans can also be extracted into by-products such as soybean oil, soybean powder, and soybean paste. It can be said that soybeans are a very versatile and economical food.

2. Choose high-quality protein

Secondly, we need to understand what high-quality protein is. Protein is one of the essential nutrients for the human body. Among them, there are 9 kinds of amino acids that the human body cannot synthesize by itself and must be taken from food. These amino acids are called essential amino acids. High-quality protein refers to proteins that contain a full range of essential amino acids, sufficient quantities, and appropriate proportions, and are more suitable for human needs. For example, foods such as milk, eggs, pork, beef, and soybeans are all high-quality proteins.

3. Did you know that soybeans are also high-quality protein?

Once again, we need to explain why soybeans are also high-quality proteins. Isn't it said that patients with kidney disease cannot eat plant proteins? This involves a misunderstanding: many people believe that plant proteins are not high-quality proteins because their essential amino acid content is insufficient or unbalanced. However, this statement is inaccurate, because there are differences between plant proteins. The essential amino acid content and ratio of some plant proteins are very reasonable, such as soybeans. Modern research has confirmed that: except for the slightly lower content of methionine in the amino acid composition of soybeans, the quantity and composition ratio of the remaining essential amino acids are close to those of whole egg protein and pork. As a plant, the first, second, and third of the above high-quality protein standards are met, which is comparable to eggs and pork. Perfect, right?

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4. The mysterious benefits of soybeans

Finally, let's talk about the benefits of soybeans. In addition to high-quality protein, soybeans also contain many other ingredients that are beneficial to the human body, such as:

1. Soy isoflavones: This is a type of phytoestrogen that has similar properties to estrogen in non-human primates. It can regulate women's endocrine balance, relieve menopausal symptoms, and prevent breast cancer and endometrial cancer. For men, soy isoflavones also have a certain protective effect and can inhibit the proliferation and metastasis of prostate cancer cells.

2. Unsaturated fatty acids: This is a fatty acid that is beneficial to the cardiovascular system. It can lower the cholesterol and triglyceride levels in the blood, prevent atherosclerosis and coronary heart disease, etc. Soybeans contain a lot of linoleic acid and linolenic acid, both of which are essential fatty acids that the human body cannot synthesize on its own and must be taken from food.

3. Dietary fiber: This is a substance that is beneficial to the digestive system. It can increase intestinal motility, promote defecation, prevent constipation and colon cancer, etc. Soybeans are rich in soluble and insoluble fiber, which can effectively regulate blood sugar and cholesterol levels.

I believe that through the above introduction, everyone should have a comprehensive understanding of soybeans: soybeans are a very healthy and delicious food. For patients with chronic kidney disease, it is not only okay to eat, but also recommended! Of course, this does not mean that you can eat soybeans or soy products without restraint, because any food must be consumed in moderation to achieve the best effect.