China's Journal Rankings: A Cautionary Tale for Global Science

China's decision to close its influential journal ranking list, reported by Nature on May 26, 2026, sends ripples through the global scientific community. For health optimizers and biohackers, this move challenges how we evaluate the evidence behind supplements, longevity protocols, and wellness trends. The closure of the Chinese Academy of Sciences (CAS) Journal Ranking, which classified over 10,000 journals into quartiles based on impact factor and other metrics, aims to reduce perverse incentives that prioritize publishing in high-impact journals over conducting rigorous, reproducible science. In health and longevity research, the stakes are high: studies on NAD+ precursors, intermittent fasting, or cold exposure often gain traction based on where they are published. If the ranking system encouraged a 'publish or perish' culture that favored flashy results, the evidence base for many biohacking protocols could be weaker than assumed.

The Science

The Chinese Academy of Sciences (CAS) Journal Ranking has been a cornerstone for evaluating research output in China, classifying over 10,000 journals into quartiles based on impact factor and other metrics. According to Nature, this system directly influenced funding, promotions, and even the direction of research. The closure, described as a cautious step, aims to reduce the perverse incentives that prioritize publishing in high-impact journals over conducting rigorous, reproducible science. The pressure to publish in Q1 journals has been linked to the reproducibility crisis in biomedicine, where many findings—especially in nutrition and supplements—fail to replicate. For example, a 2021 study in Nature Human Behaviour found that less than 50% of social psychology studies replicated successfully, and similar rates are observed in nutritional research. If the Chinese system encouraged the publication of flashy but fragile results, the closure could be a step toward more robust science. However, there is also a risk that researchers lose a clear guide for evaluating quality, potentially leading to greater heterogeneity in standards.

The end of China's journal rankings is a wake-up call: impact factor is not a proxy for truth, especially in health science. The system's focus on quartiles created a hierarchy that influenced not only where scientists published but also what they studied. For instance, longevity research might have skewed toward molecular mechanisms rather than practical, reproducible interventions. The closure prompts a necessary recalibration: we need to value replication, data transparency, and clinical relevance over journal prestige. This aligns with the San Francisco Declaration on Research Assessment (DORA) principles, which emphasize evaluating research on its own merits. For health practitioners and self-experimenters, this means learning to read beyond the journal name and assess study design, sample size, and conflicts of interest.

Key Findings

• Scale of impact: The CAS ranking covered more than 10,000 journals across all disciplines, including biomedicine and health sciences. Its closure affects how Chinese researchers prioritize their work, and given that China produces the second-largest share of scientific publications worldwide, the global impact is substantial.
• Incentive distortion: The quartile system (Q1 to Q4) created pressure to publish in top-tier journals, potentially encouraging questionable research practices like selective reporting or p-hacking. A 2022 meta-analysis in BMJ Evidence-Based Medicine showed that studies with positive results were 3 times more likely to be published in high-impact journals than those with null results.
• Global influence: China now produces the second-largest share of scientific publications worldwide. Changes in its evaluation system will inevitably affect global research quality and collaboration. Other countries with similar ranking systems, such as South Korea and Japan, may follow suit.
• Reproducibility concerns: The focus on impact factor has been linked to the reproducibility crisis in biomedical research, where many findings—especially in nutrition and supplements—fail to replicate. For example, a 2023 meta-analysis on NMN in Aging Cell showed mixed results, suggesting caution in interpreting individual studies.

Why It Matters

For the biohacking community, this is more than academic politics. Protocols like taking NMN for longevity or using saunas for cardiovascular health often rely on studies published in high-impact journals. If those journals were prioritized over methodological soundness, the advice you follow might be built on shaky ground. The CAS ranking's closure prompts a necessary recalibration: we need to value replication, data transparency, and clinical relevance over journal prestige. Moreover, this move could accelerate the adoption of alternative metrics, such as the San Francisco Declaration on Research Assessment (DORA) principles, which emphasize evaluating research on its own merits. For health practitioners and self-experimenters, this means learning to read beyond the journal name and assess study design, sample size, and conflicts of interest. For instance, a study on metformin as an anti-aging drug published in a Q1 journal might carry more weight than it deserves if not replicated. The closure could lead to a reevaluation of how such studies are funded and published.

Your Protocol

1. 1Triangulate evidence: Before adopting a new supplement or therapy, check if the key studies have been replicated. Use resources like PubMed's 'Similar articles' feature or systematic reviews. For example, the 2023 meta-analysis on NMN in Aging Cell showed mixed results, suggesting caution.
2. 2Follow open science: Support researchers who pre-register their studies and share raw data. Platforms like the Open Science Framework (OSF) can help you find more trustworthy research. Pre-registration reduces the risk of p-hacking and selective reporting.
3. 3Diversify your sources: Don't rely solely on studies from top-tier journals. Look for findings in specialty journals that may have more rigorous peer review for your area of interest. Also, consider preprints from arXiv or bioRxiv, but be aware they are not peer-reviewed.

What To Watch Next

Expect the Chinese Academy of Sciences to announce a new evaluation framework within the next year. Possible directions include a shift toward qualitative peer review, use of altmetrics (like social media mentions or policy citations), or a focus on research that addresses national health priorities. Globally, other countries may follow suit, moving away from simplistic ranking systems. Organizations like DORA are gaining traction, promoting article-level metrics over journal impact factor. For the health-conscious reader, this is an opportunity to become a more critical consumer of science. The next wave of longevity research will likely emphasize transparency and reproducibility. Stay tuned for updates from Nature and other outlets as this story develops.

The Bottom Line

China's closure of its journal ranking list is a bold move that could improve the integrity of health research. For now, take it as a reminder: journal prestige is not a guarantee of truth. When optimizing your health, demand evidence that stands up to scrutiny. The future of longevity science depends on it. By adopting a more critical approach—triangulating evidence, supporting open science, and diversifying sources—you can make better-informed decisions for your health and longevity.