Major health publishers experienced dramatic visibility declines following Google's December 2025 core update, raising concerns about AI-driven search cannibalizing organic traffic.
Authoritative health publishers have experienced substantial visibility losses following Google’s December 2025 core update, according to data shared by SEO expert Lily Ray on January 20, 2026. The visibility index chart reveals steep declines across multiple established medical information websites that previously maintained dominant positions in search results for years.
Ray, an SEO strategist, posted on social media expressing surprise at the severity of impacts affecting health publishers. “Really wild to see authoritative health publishers who have dominated in SEO for many years get hit so hard by this last core update, across various media networks,” Ray wrote. The observation sparked immediate discussion within the search marketing community about potential correlations between AI Overview deployment and organic traffic erosion.
The visibility index tracking data demonstrates pronounced downward trajectories for six major health information websites: healthline.com, medicalnewstoday.com, everydayhealth.com, webmd.com, verywellhealth.com, and verywellmind.com. The chart spans from June 2021 through January 2026, revealing that several sites reached peak visibility levels around mid-2024 before experiencing accelerating declines through late 2025 and early 2026.
WebMD maintained visibility scores exceeding 300 points during its peak period in mid-2024. By January 2026, the site’s visibility dropped to approximately 170 points, representing a decline of roughly 43% from peak levels. Healthline.com showed similar patterns, with visibility falling from approximately 250 points to around 120 points over the same period.
MedicalNewsToday.com, VeryWellHealth.com, and VeryWellMind.com demonstrated comparable trajectories, though operating at different absolute visibility levels throughout the tracking period. EverydayHealth.com maintained relatively stable positioning in the lower range, fluctuating between approximately 20 and 60 visibility points across the entire timeframe.
The timing of accelerated declines corresponds with Google’s December 2025 core update rollout, which began on December 11, 2025, and concluded after 18 days on December 29. Industry tracking tools detected significant volatility beginning December 13, approximately two days after the initial announcement.
Ray proposed a theory connecting the visibility declines to Google’s AI Overviews feature. “Wondering if there is some cycle where content is now being answered by AI Overviews → less engagement for informational sites → lower rankings over time,” she wrote in the January 20 post. The hypothesis suggests a feedback loop where AI-generated summaries reduce user engagement with traditional organic listings, subsequently affecting quality signals that influence rankings.
The December update represented Google’s third confirmed core algorithm modification of 2025, following March and June updates earlier in the year. Multiple tracking platforms including Semrush, Advanced Web Rankings, Mozcast, Sistrix, Cognitive SEO, SimilarWeb, Accuranker, Mangools, Wincher, Data For SEO, SERPstat, and Algoroo recorded substantial ranking movements beginning December 13.
Glenn Gabe, a prominent algorithm analyst, documented significant movement across thousands of previously impacted sites. “This is the 12/14 edition of ‘Core Update Notes’. As expected, the update is landing, and in a big way for some sites already. I’m seeing big swings in search visibility based on running the numbers for over 3K sites previously impacted by major updates,” Gabe posted on December 14, according to PPC Land’s documentation.
Research published in May 2025 found that AI Overviews reduce organic click-through rates substantially. Desktop users clicked external links just 7.4% of the time when AI Overviews appeared, compared to 28% without them. Mobile users demonstrated higher click-through rates at 19% with AI Overviews present versus 38% without the feature.
Health-related queries showed particular susceptibility to AI Overview impact. The research documented that health YMYL (Your Money, Your Life) queries achieved 52% average scroll depth, indicating users consumed substantial portions of AI-generated content before deciding whether to click through to external sources. The study tracked 70 users across eight search tasks, revealing that most users never viewed content beyond the first third of AI-generated summaries.
The health sector impacts align with broader patterns observed during the December update. British news publishers faced brutal rankings collapse, with analysis from Sistrix revealing The Guardian dropped 30 points in visibility score to 228.9, while The Telegraph fell 19 points to 43.9. More than two-thirds of major UK news websites lost search visibility between December 11 and December 29, 2025.
India-based news publishers experienced similarly severe consequences, according to Sistrix visibility data shared by Will Flannigan, Senior SEO Editor for The Wall Street Journal. Hindustantimes.com visibility dropped from above 6 points to below 2 points on the Sistrix index, representing approximately 67% decline. Indiatimes.com and Indianexpress.com showed comparable drops throughout the December update rollout.
The concentration of impacts across specific content categories distinguished the December update from previous algorithm adjustments. Gabe’s analysis indicated he was seeing significant news publisher volatility, suggesting the update’s quality evaluation systems particularly affected news and media properties. Publishers reported impacts across multiple Google surfaces simultaneously, including Discover, Google News, Top Stories, and the News tab in Search.
Market concentration data compounds concerns about visibility losses for health publishers. Research published in April 2025 revealed that 16 media companies control the vast majority of content appearing in Google search results. In the health sector, Red Ventures’ properties Healthline and MedicalNewsToday collectively receive over 310 million monthly visits from search, while Ziff Davis’ MayoClinic captures 342 million monthly visits.
These conglomerates achieved dominant positions through aggressive acquisition strategies, purchasing established websites and leveraging existing domain authority to rapidly launch new properties. The December update’s impact on several properties within these networks suggests algorithmic changes affected evaluation criteria applied to large-scale health content operations.
Historical data from previous core updates demonstrates limited recovery patterns for sites experiencing substantial visibility losses. Google’s June 2025 core update enabled partial recoveries for websites previously impacted by the September 2023 Helpful Content Update, though many sites experienced mixed results requiring 16 days to fully implement.
Recovery patterns emerged primarily between July 8-9, several days after initial ranking movements began. Multiple tracking platforms detected substantial ranking movements beginning July 2, approximately 48 hours after the June 30 announcement. According to Gabe’s tracking data, many sites saw partial recoveries ranging from 20% to 80% increases, though few achieved full restoration to pre-impact visibility levels.
Websites experiencing ranking improvements during the June update also gained visibility in enhanced search features. Sites showing improved rankings appeared more frequently in top stories, AI Overviews, AI Mode, and rich results, suggesting that Google’s quality assessment systems underwent significant recalibration affecting multiple search surfaces simultaneously.
The pattern suggests that sites affected by core updates face prolonged recovery timelines requiring multiple subsequent update cycles. Google’s guidance indicates that meaningful ranking improvements often require sustained content quality improvements rather than immediate technical modifications. Sites remaining in algorithmic gray areas face continued volatility as Google adjusts system parameters.
The health publisher visibility declines occurred as Google expanded AI Overviews globally. The company rolled out the feature to nine European countries on March 26, 2025, including Germany, Spain, and Italy, extending coverage beyond initial United States deployment. When AI Overviews first launched in the United States, some publishers reported traffic reductions as high as 90% for pages that previously ranked highly for queries now answered directly by AI summaries.
Google VP Dan Taylor stated in January 2026 that AI Overviews accumulated more than 2 billion monthly active users. The company expanded AI Overview ads to 11 countries on December 19, targeting English speakers with text and shopping ads across Australia, Canada, India, and eight additional markets. People click and engage with AI Overview ads at approximately the same rate as traditional search ads, according to Taylor’s comments to Business Insider.
Independent publishers filed a formal antitrust complaint with the European Commission on June 30, 2025, targeting Google’s AI Overviews feature. The complaint alleged abuse of market power in online search and requested interim measures to prevent irreparable harm. The Independent Publishers Alliance document stated that Google’s core search engine service misuses web content for AI Overviews, causing significant harm to publishers in the form of traffic, readership and revenue loss.
Traffic decline studies demonstrate measurable impacts on publisher revenue streams. The complaint centered on publishers’ inability to opt out from AI training and content crawling without losing visibility in Google’s general search results. Publishers using Google Search do not have the option to opt out from their material being ingested for Google’s AI large language model training without losing their ability to appear in general search engine results pages, according to the complaint documentation.
BuzzFeed disclosed significant concerns about AI search features in quarterly filings released August 7, 2025. The media company outlined specific risks from Google’s AI Overviews and AI Mode, which provide direct answers in search results and potentially reduce user engagement with publisher websites. AI-generated summaries often provide answers directly on the search results page, which could lead to fewer users clicking through to publisher websites, according to BuzzFeed’s Form 10-Q filing.
SEO expert Dan Callis issued a stark warning about the future of search engine optimization, predicting Google could eventually eliminate all organic website listings in favor of AI-generated responses. The veteran marketer coined the term “Zero Result SERP” to describe a hypothetical scenario where Google provides only AI-generated answers without any traditional website links.
New data reveals Google’s AI Overviews have already reduced organic clicks by 34.5% when present in search results. Ryan Law, Director of Content Marketing at Ahrefs, noted the correlation between AI Overview presence and reduced user engagement with traditional search results. The research analyzed 300,000 keywords and found that the presence of an AI Overview correlated with a 34.5% lower average click-through rate for the top-ranking page.
Additional studies reveal broader impacts on search behavior. Zero-click searches on Google increased from 56% to nearly 69% since AI Overviews launched in May 2024, according to documented research. The transformation affects different types of content unequally, with technical queries requiring detailed explanations maintaining higher click-through rates compared to simple factual questions easily answered within AI Overviews.
For health publishers specifically, the December update impacts compound existing challenges from market concentration and platform dependency. Research published in August 2025 found that Google Discover accounted for two-thirds of referrals to news and media websites, making any algorithmic changes to that surface particularly devastating. The December update affected both traditional search results and Discover traffic simultaneously, with some publishers reporting complete elimination of Discover impressions within 48 hours.
The timing proved particularly harsh for content publishers. Seasonal advertising rates typically peak in December as brands increase spending for holiday campaigns. Instead, hundreds of website operators faced dramatic traffic declines during what should have been their most lucrative period. Publishers reported traffic declines ranging from 70-85%, with some experiencing a 98% drop in Google Discover impressions.
Google described the December update as a “regular update designed to better surface relevant, satisfying content for searchers from all types of sites,” according to the Google Search Status Dashboard. The company provided no additional guidance specific to the December deployment beyond standard recommendations to focus on content quality improvements rather than technical manipulation.
The update’s 18-day implementation period exceeded typical deployment timelines observed in previous core updates throughout 2025. Google’s March 2025 core update lasted 14 days and concluded on March 27, while the June update required 16 days to complete. This December deployment arrived approximately five months after the June update, breaking from typical quarterly patterns.
Historical data shows Google generally releases core updates every three to four months, though the company maintains no fixed schedule for these algorithmic adjustments. The frequency of major updates has increased notably since 2024, with Search Engine Roundtable data showing numerous unconfirmed ranking fluctuations between official announcements throughout 2025.
The health sector represents particularly sensitive content for search quality evaluation. Your Money, Your Life (YMYL) content categories, which include health and medical information, face heightened scrutiny due to potential real-world consequences of misinformation. Google’s quality rater guidelines emphasize expertise, authoritativeness, and trustworthiness (E-A-T) for YMYL content, though the specific technical implementations of these concepts within ranking algorithms remain undisclosed.
Publishers implementing content strategies specifically optimized for AI Overviews face uncertain prospects. Some industry observers suggest that traditional SEO approaches focused on ranking individual web pages through keyword optimization and backlink profiles differ substantially from requirements for appearing in AI-generated summaries. AI search optimization requires understanding how models synthesize information from multiple sources to generate original recommendations.
Social media responses to Ray’s January 20 post revealed widespread concern among SEO professionals about the sustainability of content-driven business models. One commenter suggested that “all their info was sucked up by ai and people are now getting it from ai tools.” The observation noted that while predatory, large language models provide superior user experience for obtaining answers compared to traditional search results.
Another industry participant questioned whether affected sites were “just getting caught for the ‘AI search’ optimizing they were doing,” suggesting potential penalties for aggressive optimization tactics specifically targeting AI-powered search features. The comment reflected ongoing debates within the SEO community about appropriate strategies for maintaining visibility as search interfaces transform.
The December update occurred amid broader industry consolidation and platform power concentration. AdExchanger’s December 24 documentation showed strategic buyers accounted for 71% of scaled ad tech transactions during 2025’s first three quarters compared with 58% during the same period in 2024, indicating accelerating consolidation within digital advertising infrastructure.
The concentration of power became increasingly evident through the December period. Google’s algorithm update affected traditional search results and Discover traffic simultaneously, suggesting modifications to fundamental content evaluation systems rather than surface-level ranking factors. Some websites experienced complete disappearances from search results during the rollout, with one forum participant whose site exceeded 10 years in age reporting losing all rankings overnight despite never utilizing artificial intelligence for content generation.
Recovery prospects remained uncertain for affected sites. Google’s standard guidance suggests that meaningful ranking improvements often require subsequent core update cycles rather than immediate content modifications. Historical data from previous updates shows limited recovery patterns even months after implementation, with sites experiencing substantial traffic losses often struggling to regain previous visibility levels.
Who: Major health information publishers including healthline.com, medicalnewstoday.com, everydayhealth.com, webmd.com, verywellhealth.com, and verywellmind.com experienced visibility declines. Lily Ray, an SEO strategist, documented and analyzed the impacts. Glenn Gabe tracked broader algorithm volatility affecting thousands of sites.
What: Authoritative health publishers suffered substantial visibility losses following Google’s December 2025 core update. Visibility index data reveals WebMD declined approximately 43% from peak levels around 170 points in January 2026. Multiple established medical information sites that maintained dominant search positions for years experienced steep downward trajectories. The impacts coincided with accelerated deployment of Google’s AI Overviews feature, which generates summaries directly in search results.
When: The declines accelerated following Google’s December 2025 core update, which began December 11, 2025, and concluded December 29 after an 18-day rollout. Visibility tracking from June 2021 through January 2026 reveals several health publishers reached peak visibility around mid-2024 before experiencing sustained declines through late 2025 and early 2026.
Where: The visibility losses affect health publisher performance in Google Search results globally, including traditional organic listings, Google Discover feeds, and AI Overviews. Research indicates AI Overviews now operate in over 200 countries with more than 2 billion monthly active users. The December update impacted multiple Google surfaces simultaneously, including web search, Discover, Google News, and Top Stories boxes.
Why: Ray hypothesized that AI Overviews create a feedback loop where AI-generated summaries reduce user engagement with organic listings, subsequently affecting quality signals that influence rankings. Research shows AI Overviews reduce organic click-through rates by 34.5% when present. Health YMYL queries demonstrated 52% average scroll depth in AI-generated content, indicating users consume substantial information before clicking external sources. The December update represented Google’s third major core algorithm modification of 2025, affecting fundamental content quality evaluation systems.
Your go-to source for digital marketing news. Get the latest updates from Google, Meta, Amazon, and The Trade Desk. Stay informed on ad tech innovations, programmatic trends, and policy changes.