Protein Powders and Cancer: Understanding the Scientific Data

A Wave of Alarming Headlines About Protein and Cancer

In the first half of 2025, Russian and foreign media reported on the "deadly danger" of sports nutrition. British colorectal surgeon James Kinross claimed that excessive use of protein powders may increase the risk of colon cancer. According to him, the processing of proteins in the body produces toxic byproducts that can cause inflammation and intestinal cancer. Additionally, protein supplements significantly alter the gut microbiome, disrupting the balance of beneficial bacteria.

What Experts Say

However, Russian oncologists and dietitians categorically disagree with these conclusions. Oncologist Vladimir Ivashkov notes: powdered protein cannot provoke cancer. Such consequences can only occur if a person consumes exclusively protein powder or shakes, completely replacing other foods.

Dietitian Yulia Alexeeva adds: "To date, there is no direct evidence that moderate consumption of quality protein powder (such as whey or plant-based) causes cancer in healthy individuals". According to her, if the product does not exceed the levels of heavy metals like mercury, lead, and arsenic, then the product is safe.

Lack of Scientific Evidence

An analysis of international databases PubMed and Cochrane shows that there are no studies confirming a causal relationship between the consumption of protein supplements and tumor growth. The publications cited by tabloids either have not undergone scientific peer review or rely on laboratory observations without clinical evidence.

Some of the articles that caused an uproar concerned experiments on animals, where accelerated cell division was observed with excessive protein consumption. Scientists emphasize that this data cannot be directly applied to humans, especially considering dosages that far exceed actual consumption.

Quality and Composition Matter

An important nuance: the term "protein products" often encompasses completely different substances—from high-quality whey concentrates to cheap mixtures with additives, sugars, flavorings, and even heavy metals. According to dietitians, it is the latter that may potentially be harmful—but due to their composition, not because of the protein.

Real Risk Factors

Doctors remind us that excessive consumption of red meat, alcohol, and smoking can also provoke the development of intestinal cancer. These factors harm the colon and cause mutations in cells. Furthermore, the incidence of intestinal cancer among young people has increased by 80% over the past 30 years, which scientists attribute to worsening environmental conditions, rising obesity, the presence of microplastics in drinking water, and the mass consumption of ultra-processed foods.

The conclusion of specialists is unequivocal: moderate consumption of quality protein as part of a balanced diet poses no threat to healthy individuals.