“A celebrity drinks protein powder for years and ends up with kidneys that look ‘70 years old’?” This sentence has been popping up on many people’s screens over the past few days. According to the person’s own account, as covered by multiple media outlets, Xiang Zuo mentioned on a TV show that he had been drinking protein powder for a long time and that his kidney function was “overaged.” However, according to reports, as early as 2019 his family had explained on a program that this was related to multiple factors — years of injuries from martial arts training and long-term use of painkillers — and was not solely about protein powder. Let’s be clear up front: this is one individual’s self-reported case, and it cannot be taken as evidence that “drinking protein powder causes problems.” Can protein powder be consumed at all? How much per day is appropriate? And who should be careful? This article explains it all at once, to help older family members who want to supplement protein avoid detours.

1. What Exactly Is Protein Powder? Let’s Get This Straight First

According to a summary republished by Xinhuanet from Beijing Youth Daily, protein powder is generally a powdered supplement made by purifying soy protein, casein, whey protein, or combinations of these, used to supplement protein for people whose protein intake or absorption is insufficient. In plain terms, it is a “supplement,” not a nutrient that everyone needs.

For normal healthy people, as long as their three daily meals include fish, poultry, eggs, meat, milk, and soy products, protein intake is usually sufficient. According to the Dietary Guidelines for Chinese Residents (2022), the daily recommendation is an average of 120-200 g of fish, poultry, eggs and meat, more than 300 ml of milk, and 25-35 g of soybeans and nuts; materials from the Chinese Nutrition Society put the reference protein intake for adults at about 65 g per day for men and 55 g per day for women. So first check whether you are actually deficient, and only then decide whether extra supplementation is needed.

2. High Protein and Kidney Load: The Key Question Is “For Whom”

Many people worry: if you consume too much protein, does the kidney have to work overtime? This needs to be looked at in two situations.

For healthy adults, current evidence is insufficient to prove that moderate or relatively high protein intake damages kidney function. Several systematic reviews and meta-analyses (such as one in the Journal of Nutrition from 2018) found that after a high-protein diet, healthy adults show a slight short-term increase in glomerular filtration rate, but no differences across multiple other indicators, which is mostly viewed as a physiological adaptation of the body. The long-term effects remain uncertain.

But for people who already have chronic kidney disease (CKD), the picture is different. According to the national industry standard Dietary Guidelines for Patients with Chronic Kidney Disease (WS/T 557—2017), protein intake should be restricted by disease stage and under medical supervision: 0.8-1.0 g per kg of body weight per day is recommended for CKD stages 1-2, 0.6-0.8 g for stages 3-5 without dialysis, and 1.0-1.2 g for those on dialysis, with at least 50% coming from high-quality protein. (These are stage-specific recommended amounts in the industry standard intended for professional reference; patients’ actual intake should follow the treatment plan of their attending physician.) In other words, with the same protein, people with poor kidney function need “the right amount, per medical advice,” not self-increasing the dose.

3. These Groups Should Ask a Doctor Before Taking Protein Powder

Based on publicly available science communication summaries, the following groups should consult a doctor before supplementing with protein powder, rather than deciding on their own:

  • People with renal insufficiency or chronic kidney disease;
  • People with liver disease, especially cirrhosis and hepatic encephalopathy;
  • People with gout or hyperuricemia;
  • People allergic to relevant ingredients;
  • People in the acute phase of illnesses such as acute pancreatitis or gastrointestinal failure.

In addition, the 2023 edition of the reference intake levels raised the recommended protein intake for people over 65; however, whether to add extra powder and how much still requires consulting a medical professional based on individual circumstances — the guidelines provide reference values, not a personalized dosage prescription.

4. Three Common Misconceptions — Don’t Be Misled

Misconception 1: Taking protein powder inevitably “adds a burden” to the kidneys. The rumor-debunking platform of Kexue Zhongguo (Science China) puts it clearly: you cannot simply assume that taking protein powder creates a kidney burden; whether it does depends on the total protein intake over the long term from all sources and the individual’s kidney processing capacity. The key is whether the total amount exceeds what the individual can handle, not the words “protein powder” themselves.

Misconception 2: Eating more protein is always harmless. What the guidelines advocate is “raising the proportion of high-quality protein,” not increasing total protein intake without limit. Fixing the structure of your daily diet matters more than blindly adding powder.

Misconception 3: Treating a single case as a rule. Xiang Zuo’s kidney function claim is his own self-report, and according to reports, the “martial arts injuries plus long-term painkiller use” mentioned by his family constitutes a multi-factor background; no causal relationship between protein powder and abnormal kidney function can be inferred from it.

5. If These Situations Arise, Don’t Tough It Out Alone

If an elderly family member experiences obvious discomfort while supplementing protein, or already has underlying conditions such as kidney disease, liver disease, or gout, don’t try to figure it out alone — go to the hospital promptly and tell the doctor truthfully about their daily diet and supplements. What you really need to do day to day is just a few things: first assess whether you are actually protein-deficient, prioritize getting protein from food, ask a doctor first if you have underlying conditions, and don’t treat supplements as a nutrient where “more is better.”

When it comes down to it, protein powder is a tool: used properly it helps, used wrongly it causes trouble. Do any of your elderly family members drink protein powder? Whose advice did they follow when buying it? Share in the comments, and give a heads-up to friends who are also uncertain.