Older men most likely to reach for saltshakers, while women’s salt-adding behavior more nuanced, study suggests

Habit of adding salt to food after preparation depends on different factors for men and women, study shows, highlighting a behavior that can have severe consequences on overall health

Frontiers

Facebook

X
Bluesky
Email

Salt has been used as seasoning and food preservative for thousands of years, but having too much of it can lead to various diseases, including high blood pressure, cardiovascular diseases, and kidney disease. Salt overconsumption is also known to accelerate cognitive decline. To avoid increased likelihood of developing such diseases due to salt overconsumption, the WHO recommends adults consume no more than five grams of salt per day.

Salt added to food after preparation accounts for 6-20% of total salt intake. It is known that the behavior varies among socio-demographic groups, but in different cultural and social settings it is not always clear who is most likely to reach for the saltshaker. In a new Frontiers in Public Health study, scientists in Brazil set out to find who among older adults is most likely to do so.

“Adding salt to food at the table remains a relatively common habit among Brazilian older adults and occurs more frequently among men than among women,” said first author Dr Flávia Brito, an associate professor at Rio de Janeiro State University.

“Women’s salt-adding behavior, however, was associated with a wider range of social and dietary characteristics than men’s,” added co-author Dr Débora Santos, a titular professor at Rio de Janeiro State University.

Who likes it extra salty?

The study used survey data from 2016 and 2017 from more than 8,300 Brazilian adults aged 60 years or over. Participants recalled their dietary choices over the previous 24 hours and were asked if they do or don’t have the habit of adding extra salt at the table. Independent variables the researchers included in their analysis were sex, age groups over 60, years of education, whether people lived alone or with others, household income, area of residence, and whether participants included ultra-processed foods, fruits, and vegetables in their diets.

The findings showed that 12.7% of men and 9.4% of women added salt to their foods. Between sexes, different socio-demographic factors were identified to influence salt use at the table.

“Among men, few variables were associated with the habit of adding salt, suggesting that their behavior may be less directly related to specific dietary patterns,” Brito pointed out.

“On the other hand, women’s salt-adding behavior appeared to be more closely linked to broader dietary patterns and contextual characteristics,” added Santos.

Among men, only two factors were significantly associated with adding extra salt. Those on a special diet for high blood pressure were less than half as likely to do so than their counterparts following no such diet. Men who lived alone were 62% more likely to add salt than those living with others. Women’s odds were 68% higher if they did not follow a diet to manage high blood pressure. If they lived in urban areas or often ate ultra-processed foods, the odds doubled. For women who regularly consumed fruits or vegetables, however, the likeliness was 81% or 40% lower, respectively. This could be due to this group paying more attention to diet quality, including reduced salt intake.

Salty habits

The team pointed out that the study doesn’t uncover causal relationships. In addition, salt-adding behavior was self-reported by participants and therefore the data may be biased. It is also possible that salt use has changed since the time of surveying.

Adding extra salt may be due to both taste and habit, the team said. Repeatedly eating high-sodium foods can reduce sensitivity to salty flavors, which may lead to individuals preferring stronger saltiness. Yet, adding extra salt can be more about habit than about improving taste. To reduce overall salt consumption, measures to lower sodium contents in industrialized and ultra-processed foods are needed.

In addition to measures relating to food production, particularly processed foods, there also are measures everyone can take individually. Given the differences between men’s and women’s salt-adding behavior, the researchers said that campaigns aiming to decrease the additional use of salt should be tailored to different population groups, including gender and lifestyle characteristics

“The use of herbs and natural seasonings as alternatives to salt or culinary techniques such as using the acidity of citrus fruits may help reduce discretionary salt use while maintaining food palatability,” concluded Santos. “Practical strategies, such as avoiding the routine placement of saltshakers on the table, may also help reduce habitual salt use.”

---

Journal

Frontiers in Public Health

DOI

10.3389/fpubh.2026.1737516 

Method of Research

Data/statistical analysis

Subject of Research

Not applicable

Article Title

The habit of adding salt to food at the table and its association with socio-demographic, anthropometric and dietary characteristics in Brazilian older adults

Article Publication Date

2-Apr-2026

 

Proof for theory of visual perception

1981 Nobel Prize-winning model confirmed correct

Technical University of Munich (TUM)

Facebook

XLinkedInWeChat
WhatsAppEmail

Already in the 1960s, Hubel and Wiesel proposed a model according to which visual perception is the result of orderly, stepwise computations in the brain – with specialized neurons in the cortex responding selectively to specific features, such as edges or the orientations of moving objects. While widely celebrated, important aspects of the theory remained an issue of debate: does this feature selectivity already originate in the thalamus, or does it emerge later in the cortex? The new study addresses this question directly by analyzing signal transmission at individual synapses between the thalamus and the visual cortex - something that had not previously been possible.

The research team, led by Prof. Arthur Konnerth, Dr. Yang Chen, and PhD student Marinus Kloos at the Institute of Neuroscience at the TUM School of Medicine and Health and the Munich Cluster for Systems Neurology (SyNergy), developed a high-resolution imaging approach to measure synaptic activity in the intact brain. Their findings directly confirm core predictions of the Hubel and Wiesel model. The new research results were published in the prestigious journal Science.

“Our results highlight how remarkably accurate and forward-looking Hubel and Wiesel’s insights were,” says Prof. Konnerth. “Modern neuroscience – and even artificial neural networks – continue to build on their principles. Learning from biological systems remains a powerful driver of technological innovation.”

What exactly did the TUM researchers do?

When we see, signals travel from the eye first to the thalamus, a relay station deep in the brain, and from there to the visual cortex at the back of the head. In the first area of this visual cortex, known as the primary visual cortex, simple image features like edges, contrast, and orientation are processed. The TUM researchers specifically examined this segment – the connection from the thalamus to this initial visual area of the cortex – in mice.

Using two-photon microscopy, the researchers visualized individual synapses in the living brains. They employed fluorescent proteins that emit light when synaptic transmission occurs, allowing them to track activity at specific neuronal contact points in real time. At the same time, the animals were presented with simple visual stimuli, such as horizontal and vertical stripes, enabling the team to map which synapses responded to which orientations.

To distinguish direct input from the thalamus from signals generated within the cortex, the researchers used optogenetics. They equipped certain neurons with light-sensitive proteins and could thus temporarily "mute" parts of the cortex with light. So, they could determine whether synaptic activity persisted (indicating thalamic input) or disappeared (indicating intracortical processing).

This approach allowed the team to separately quantify thalamocortical and corticocortical inputs. The results were clear: signals arriving from the thalamus were robust but largely non-specific with respect to orientation. In contrast, orientation selectivity - such as distinguishing horizontal from vertical lines - emerged only through processing within cortical circuits.

These findings resolve a long-standing controversy. The new data show directly that, in mammals, the cortex constructs this information step by step from broadly tuned inputs – precisely as predicted by Hubel and Wiesel.

Implications for neuroscience and beyond

Beyond confirming a foundational theory, the study introduces a versatile method for analyzing synaptic function. According to the researchers, this technique can be applied to a wide range of neuron types and may help identify dysfunctional circuits in neurological disorders such as Alzheimer’s disease.

The study also revealed a fundamental difference between synapse types. Synapses within the cortex (corticocortical synapses) exhibited calcium signals associated with learning and plasticity, whereas synapses from the thalamus (thalamocortical synapses) did not.

“This was an unexpected finding,” Konnerth explains. “It suggests that not all synapses have the same capacity for adaptation and learning, challenging long-standing assumptions in neuroscience.”

---

Journal

Science

DOI

10.1126/science.aec9923 

Method of Research

Experimental study

Subject of Research

Animals

Article Title

Thalamic activation of the visual cortex at the single-synapse level

 

Unveiling a ‘conspiracy of silence’ surrounding Johnny Kitagawa’s crimes of sexual abuse

Mutual interests among media, government, and industry, not just cultural conformity, sustained silence around a major sexual abuse case

Doshisha University

Facebook

XLinkedInWeChat
WhatsAppEmail

 

image: 

The relationship and complicity between the government, media organizations, and talent agencies has been identified as a key structural factor in the suppression of abuse allegations in the Japanese entertainment industry.

view more 

Credit: interiot at Wikimedia Commons https://commons.wikimedia.org/wiki/File:Street_photo_session_with_underground_idol,_in_Akihabara_pedestrian_zone_(2006-07-09_00.19.38_by_interiot).jpg

From the 1970s onwards, few institutions in Japan could match the cultural and economic reach of the industry built by Johnny & Associates (J&A). Founded by Johnny Kitagawa in 1962, the agency managed male performers who became idols of Japanese television and shaped popular culture. Kitagawa’s cultural standing was immense; when he died in 2019, his funeral was held at the Tokyo Dome, with then-Prime Minister Abe Shinzō sending a formal message of condolence.

However, serious allegations of sexual abuse against Kitagawa had circulated for decades prior to his death. Reports of him abusing trainees and performers aged 12 to 18 years appeared in weekly magazines as early as the 1960s. In the early 2000s, Tokyo High Court proceedings found the allegations credible, and the issue was raised in a session of the National Diet of Japan. Despite this, mainstream media remained largely silent and no criminal investigation was launched. As of 2026, over 500 individuals have been compensated for abuse suffered at Kitagawa’s hands. This raises the question: how did Japanese society become broadly aware of potential criminal conduct and yet fail to act for decades?

To answer this, Professor Yukiko Nishikawa from the Graduate School of Global Studies, Doshisha University, Japan, examined the sociocultural, psychological, and institutional mechanisms behind the prolonged silence around Kitagawa’s crimes. Her latest article, published in Japan Forum on March 11, 2026, draws on sociological theory and analyses of statements from key industry figures, media organizations, and institutional reports. Parts of the case background discussed also draw on Prof. Nishikawa’s book, titled  ‘The Politics of Conformity in Japan’ (Routledge, 2025), though the analysis and arguments presented in the article are newly developed.

Previous researchers explained this silence using psychological frameworks such as the spiral of silence and the bystander effect. The former describes staying quiet when one’s views conflict with perceived majority opinion, while the latter refers to failing to intervene when others are present. While Prof. Nishikawa acknowledges these offer partial explanations, she argues they are insufficient—they describe passive processes, whereas the Kitagawa case involved active suppression.

Instead, Prof. Nishikawa characterizes the situation as a ‘conspiracy of silence.’ This denotes not a coordinated plot, but a mutually reinforcing, unspoken arrangement among institutions with shared interests in keeping the issue out of public view. “Understanding this case requires critically analyzing the broader systemic mechanisms alongside individual psychology to explain why such silence was maintained, despite widespread awareness of allegations over several decades, ” she remarks.

The study identifies structural mechanisms behind this silence. Television networks avoided negative coverage to protect access to J&A performers, later confirmed in self-assessment reports by major broadcasters. At the same time, Japan’s ‘kisha kurabu’ press system—granting journalists privileged access in exchange for uniform reporting—discouraged investigative coverage. Weak legal protections for abuse victims and government non-interference in cases involving powerful private entities ensured no external pressure. The concept of ‘sontaku,’ meaning acting on implicit expectations of powerful actors, captures how this complicity operated without overt coordination.

The study also challenges the narrative that the 2023 BBC documentary or former J&A performer Kauan Okamoto’s press conference marked a turning point. Prof. Nishikawa argues this framing reflects symbolic power, as portraying foreign media as the catalyst obscures ongoing domestic complicity and avoids accountability. “Overall, my article sheds light on the often unseen forces that shape our everyday conduct. By exploring structural dynamics, it provides a deeper understanding of the mechanisms that influence human behavior, such as silence toward potentially criminal acts,” says Prof. Nishikawa.  

Unfortunately, even after J&A’s dissolution, the study states that the underlying structural conditions remain largely intact. “There is an urgent need to reform relations among the media, the state, and industry, along with strengthening internal due diligence within each entity to protect human rights in Japan,” concludes Prof. Nishikawa. Without addressing these issues, similar patterns of institutional silence could persist or recur elsewhere.

---

About Professor Yukiko Nishikawa from Doshisha University, Japan
Dr. Yukiko Nishikawa is a Professor at the Graduate School of Global Studies at Doshisha University. Her research interests include politics and society in Japan, Japan’s diplomacy and security and politics in East and Southeast Asia. She has published several research papers and books on these topics, including: The Politics of Conformity in Japan (Routledge, 2025); Political Sociology of Japanese Pacifism (Routledge, 2018); Human Security in Southeast Asia (Routledge, 2010); Japan’s Changing Role in Humanitarian Crises (Routledge, 2005).
 

Media contact:
Organization for Research Innovation
Doshisha University
Kyotanabe, Kyoto 610-0394, JAPAN
E-mail：jt-ura@mail.doshisha.ac.jp

---

Journal

Japan Forum

DOI

10.1080/09555803.2026.2639988 

Method of Research

Case study

Subject of Research

Not applicable

Article Title

The architecture of complicity: Media, power and conspiracy of silence in the Johnny Kitagawa sexual abuse case

 THE HOUNDS OF TINDALOS

This tiny organism simply loves corners

A single-celled microorganism uses geometry to sense its world

Hokkaido University

Facebook

X
BlueskyMessageWhatsAppEmail

 

image: 

Stentor coeruleus. 

view more 

Credit: Laboratory of Physical Ethology, Hokkaido University

A surprising observation in the lab has revealed a remarkable ability in Stentor coeruleus, a single-celled organism about one millimeter long. Sometimes nicknamed the “platypus” of microorganisms for its trumpet-like shape, this tiny creature appears to have a distinct preference for corners.

For nearly two years, Assistant Professor Syun Echigoya had been working to keep these delicate organisms alive in the lab. “Maintaining protists is challenging because it requires a very careful balance of culture medium and nutrient conditions,” he explains. One day, after reading that oat grains could serve as a good food source, he added some to the culture dish.

The next day, the organisms seemed to have all disappeared. But when he lifted an oat grain under the microscope, he found S. coeruleus clustered tightly in a narrow gap between a grain and the surface below. The microorganisms had gathered in this confined space, anchoring themselves in place.

“That moment led us to suspect that they might be sensitive to surrounding geometry,” says Echigoya. “We then set out to test this idea.” Working with collaborators at the University of Toyama, the team confirmed their hypothesis. Their findings were published in February 2026 in the Proceedings of the National Academy of Sciences.

The team designed tiny chambers with precisely controlled shapes, mimicking the kinds of structures that microorganisms encounter in natural aquatic environments. Some chambers had smooth, flat surfaces, while others featured edges, angles, and tight spaces resembling corners. “We systematically changed geometric features, such as corner angle and depth, to create distinct anchoring-site options. We then did a quantitative behavioral analysis using video recordings of the microbes, complemented by numerical simulations,” adds Echigoya. 

What they observed was far from random movement. At first, the cells swam freely, exploring their surroundings. But as they approached a surface, their behavior changed. Their bodies subtly shifted into an asymmetric shape, and they began gliding along the walls, using the coordinated beating of hair-like structures called cilia. Gradually, they steered themselves toward tighter, corner-like spaces. Once there, they attached themselves firmly to the surface.

Despite being just a single cell, with no eyes, brain, or nervous system, S. coeruleus is able to navigate its environment strategically. It does this by changing its shape that allows it to sense and respond to its environment. “We were surprised by how effective this minimal strategy is,” says Echigoya. “S. coeruleus does not need to recognize structures in a cognitive sense. With a simple shift in body shape, it can physically interact with surfaces to find suitable corner spaces to attach.”

“These findings suggest that even subtle physical features in natural environments can have a big impact on where microorganisms live and how they spread. At the microscopic scale, landscapes are filled with small crevices and sheltered spaces. The ability to locate and settle into these protected niches may help explain how microorganisms survive, move, and form communities,” adds Associate Professor Yukinori Nishigami, co-author and head of the Laboratory of Physical Ethology at Hokkaido University.

Stentor coeruleus moves through a specially designed chamber, showing how it anchors itself in response to surrounding shapes. [VIDEO] |

Credit

Laboratory of Physical Ethology, Hokkaido University

Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2518816123 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Geometrical preference of anchoring sites in the unicellular organism Stentor coeruleus

Breakthrough offers endless recycling for acrylic plastics without the environmental cost

University of Bath

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Dr Jon Husband, Research Fellow from the Institute of Sustainability and Climate Change at the University of Bath (UK).

view more 

Credit: University of Bath

A breakthrough method for chemically recycling acrylic - one of the world’s most widely used plastics - has been developed by researchers at the University of Bath.

In contrast to conventional mechanical recycling, this method uses lower temperatures and sustainable solvents without losing material quality, meaning the plastic can be recycled many times over with minimal environmental impact.

Acrylic, sold under the brand names including Perspex and Plexiglas, is made from the transparent thermoplastic polymethyl methacrylate (PMMA).

Approximately 3 million tonnes are used worldwide each year, in a wide range of applications including automotive components, screens and construction materials.

The work, published in Nature Communications, was led by Dr Jon Husband and Dr Simon Freakley from the University’s Institute of Sustainability and Climate Change (ISCC) and co-authored by the Innovation Centre for Applied Sustainable Technologies (iCAST) Director Professor Matthew Davidson.

Dr Jon Husband, ISCC Research Fellow, said: “With current methods for recycling both energy intensive and inefficient, the demand for cleaner, more efficient recycling technologies has never been greater.

“Plastic recycling can be tough to make economically feasible, due to issues around high energy costs and low-quality product; this work directly addresses both of these issues.”

The Perspex problem

Mechanical recycling is the most common recycling method, which can involve shredding or melting the plastic to reform pellets for new uses. However, this leads to discolouration and a gradual decline in quality, meaning the recycled material can no longer be used for glass-like applications like screens or spectacles.

Recent industry focus has been on pyrolysis - the heating of Perspex to 350-400 °C - to turn the plastic back into its monomer building blocks to be made from scratch again, in pristine quality. However, this process is very energy-intensive and is easily contaminated by other plastics.

A cleaner, safer way to “unzip” acrylic plastics

The new process developed by the team at Bath uses UV light under oxygen-free conditions to chemically break down consumer-grade PMMA plastic into its original monomer building blocks.

Crucially, the chemistry works at 120-180°C, far below the 350-400°C typically needed for conventional pyrolysis-based recycling.

This significantly lowers the energy input needed, improving both environmental performance and commercial scalability.

High yields suitable for true circularity

The new approach delivers over 95% conversion of the plastic and yields more than 70% monomer, which can then be purified and repolymerised into “as new” materials.

Dr Simon Freakley says: “Developing new chemical recycling approaches matters because it turns waste back into pristine new materials, rather than a lower‑grade, low-value material destined for eventual disposal.

“This method allows us to recover high-quality monomers from used PMMA, offering a clear pathway toward genuine circularity in acrylic materials.”

Scalable, sustainable plastics recycling

The Bath team’s discovery advances beyond a concurrent discovery in PMMA recycling from researchers at ETH Zurich, which relies on UV‑activated chlorinated solvents to drive depolymerisation.

In contrast, the Bath team’s process is compatible with more sustainable solvents, opening the door to greener, simpler and more industrially viable recycling routes.

Currently, the team can recycle a few grams of real plastic waste at a time. Research is ongoing to improve the efficiency and scale the process.

 

The chemical processes occurring when the light interacts with the plastic when it is dissolved causes the reaction to glow blue.

Credit

University of Bath

Journal

Nature Communications

DOI

10.1038/s41467-025-67997-7 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Photo-initiated solvent-mediated depolymerization of consumer poly(methyl methacrylate) without chlorinated reagents