Why does a medicine work well for one person, but cause side effects in another? Research by Laura de Jong shows that it’s not just our DNA that matters – other medicines and illnesses can also affect how our bodies respond.

Greenhouse gas emissions related to pharmaceutical consumption increased by 77 percent over the past 24 years, according to a Leiden University study published in The Lancet Planetary Health. Moreover, efficiency gains have stalled since 2008. ‘Our best option is reducing consumption and minimising…

A flu virus could cause a pandemic. And then we would be poorly armed because flu viruses are starting to become resistant to flu medications like Tamiflu. Chemist Merijn Vriends successfully worked on an improved version of such medications. He will be awarded his doctorate on September 12th.

PhD candidate Sibel Bahtiri is one of the new Faces of Science. In videos and blogs, she will show what life is like as a young researcher.

Preventing or delaying disease often requires lifestyle changes, which turns out to be difficult. Valentijn Visch and Sandra van Dijk are researching how to help people change their behaviour.

The university has been shaping the city of Leiden for 450 years. A brief history of the university buildings that have helped define the city.

Sustainable biotechnology, new insights into genome evolution and combining forces in mathematics. The NWO has awarded grants to these three innovative Leiden research projects in the ENW-M Open Competition.

The Schoof cabinet has presented its budget. As expected, higher education is facing severe cuts. In the coming period, the Executive Board will regularly look at the consequences of what it deems an irresponsible policy.

Prof. dr. Pancras Hogendoorn is stepping down as dean of the Faculty of Medicine and vice-chair of the Executive Board of Leiden University Medical Centre (LUMC). He is also resigning from all associated secondary posts. Hogendoorn has taken his decision in anticipation of the findings of an inquiry…

From a vegan community kitchen to a green framework for drug development: sustainability became more visible in everyday campus life at Leiden University in 2025.

On the 30th of December, we received the sad message that our Kenyan colleague, Kennedy Kaminju Kariuki died on December 28, 2023 in the NW hospital in Nairobi at the age of 35 years from organ and heart failure. Kennedy was a PhD candidate at the CML, Leiden University.

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Jaïr van Rhenen studied Medicine in Leiden and is now a GP in the largely religious Veenendaal. Before this, he worked as a tropical medicine doctor in Lesotho. ‘If you have the prospect of an afterlife, you often respond differently to illness.’

Using enslaved people as servants, becoming an administrator in the Dutch West India Company or making uniforms for the colonial army. Many people from Leiden played a role in colonialism and slavery. Historians are conducting preliminary research and finding striking examples.

Like many others, Ruurd Halbertsma has had a rollercoaster of a year. His museum, the National Museum of Antiquities (RMO), was closed for a long while because of the lockdown. Visitor numbers picked up again from September, but it the next few weeks will be tense now the hospitals are full again. Halbertsma:…

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Should we cut our ties with Israel or maintain them? The event ‘A university conversation on Israel/Palestine’ on 1 July revealed the depth of feeling about the conflict, with students and staff grappling with academic values and moral dilemmas.

Career and apply for jobs

Career and apply for jobs

Career and apply for jobs

What does academic freedom mean? And how do we give shape to it in Leiden? The Academic Freedom Core Team considered these questions and presented its final report on 17 June.

It was not until 1878 that the first female students enrolled at Leiden University, but the discussion on whether women were suited to study was by no means over. 8 March is International Women's Day. BBC correspondente Kim Ghattas will deliver a lecture on 6 March on the struggle by Arabic women for…

Give organisms like plants and animals the freedom to move, interact and meet their own needs, and they will thrive on their own, says Professor Geert de Snoo. Our interference often ends up doing more harm than good.

Ionica Smeets is planning to give the prize money that she won with the Iris Medal, a prize for excellent science communication, to student projects.

Using mathematics to help children with bone cancer. It sounds a little strange, but for statistician Marta Fiocco, it's just her job. She gets a substantial grant from KiKa for it. With that money, she is going to study the effect of chemotherapy adjustments.

Researchers at Leiden University have created a unique model that mimics how disease develops after a dengue infection. This 'dengue-on-a-chip' model helps them study the virus more effectively. The timing is crucial, as climate change is causing dengue to spread worldwide.

How do organs work in the body, and how can we create mini-organs to study diseases and test new medicines? That’s the idea behind organ-on-a-chip technology. During his PhD, Flavio Bonanini worked on developing the best possible mini-livers. ‘Make them as simple as possible, and as complex as neede…

Ilze Bot wants to reduce the prevalence of cardiovascular diseases. Her research focuses on mast cells, which protect us from infections but can also make us ill.

What began as a PhD project has grown into a website with 120,000 unique visitors each year. With the platform OpenML, researcher Jan van Rijn is contributing to open science, aiming to make machine learning more transparent, accessible, and fair.

Mini organs-on-chips allow us to study how diseases develop and how drugs work. Although the technology is not new, it is becoming increasingly advanced. PhD candidate Bart Kramer hopes it will eliminate animal testing in the future.

As many as seven first-year students from the Faculty of Science were honoured as young talents. In addition, the Royal Holland Society of Sciences and Humanities (KHMW) also lauded three master's students and an astronomy project during a vibrant ceremony on 28 November. Professor of Science Communication…

Two Leiden Science researchers received an NWO-XS grant for their research. Both projects are highly promising, but also high-risk. Macrophages that trap bacteria and data storage made from 2D materials convinced the board of their potential.

The more data from cancer research we pool, the better we can search for new treatments. But how can we keep patient data safe when sharing it? Leiden researchers will tackle this challenge in a major European project.

Carel Stolker, former Rector Magnificus and President of the Executive Board of Leiden University, has been made an Officer in the Order of Orange-Nassau for his services to the city and University. Mayor Henri Lenferink awarded the royal honour to Stolker at the University’s Dies Natalis on 8 February…

‘Let’s get everyone home safely!’ This was the message of an estimated 750 demonstrators as they marched through the centre of Leiden on 18 November.

How do you detect people at high risk of heart attacks and strokes? And how can we improve the treatment of atherosclerosis? These are the questions that keep LACDR researcher Marie Depuydt busy. She is investigating the immune cells that contribute to the worsening of atherosclerosis. ‘It's a challenging…

Astronomers and surgeons from Leiden are collaborating with industry to develop an optical instrument that delivers faster, more accurate imaging of tumour tissue and abnormal blood flow during surgery.

About one and a half million people worldwide die each year from tuberculosis. For thirty years, therapy with antibiotics has been the same, while it takes far too long and can lead to resistant pathogens. Leiden researchers from four institutes are now joining forces to develop more effective and efficient…

Erection problems can have a huge impact on quality of life and health, but current diagnostic methods are painful, uncomfortable and technologically outdated. PhD candidate Evelien Trip has developed a new device that can measure erections more comfortably and painlessly.

Two consortia led by Leiden researchers have been awarded over one million euros by the Dutch Research Council and the Ministry of Health, Welfare and Sport to find solutions to antimicrobial resistance.

Jasper Knoester is the dean of the Faculty of Science. How is he doing, what exactly does he do and what does his day look like? In each newsletter, Jasper gives an insight into his life.

More than 1.3 million people worldwide die of tuberculosis (TB) each year, making research on its prevention and control essential. Researchers from various disciplines in Leiden are studying TB. A symposium on 24 March will highlight different activities in the hope of boosting nationwide collabora…

The antibiotic EVG7, developed in Leiden, has proven capable of fighting the dangerous gut bacterium C. difficile with only a minimal dose. What’s more, the bacterium is far less likely to return, a major issue with existing antibiotics. The research was published in Nature Communications.

Two research groups involving Leiden University have been awarded a major European grant, the ERC Synergy Grant. This for research on the development of membranes that can clean water and purify medical drugs and research on the biological clock in certain bacteria.

Three fundamental research projects at Leiden in physics, chemistry and medical science have received funding from the Dutch Research Council (NWO). They involve research on magnetic fields in the universe, the role of myeloid cells in cancer immunotherapy and the evolution of ancient proteins.

The SENSYN project has found a solution to few public datasets for criminological research: synthetic datasets. Marieke Liem talks about this unique innovation