How UPF Affects Female Fertility and Ovarian Health
This Research project operates within our department's Reproductive Medicine & Genetics theme and is run by Prof. Suzannah Williams.
Ultra-Processed Food & Fertility Research Project
Why research into UPF is so important?
Ultra-processed foods (UPFs) make up 60% of the UK adult diet, yet their impact on reproductive health is poorly understood. While UPF has been linked to obesity, cardiovascular disease and metabolic disorders, the effect on female fertility remains under-researched. Evidence suggests that consuming a diet high in UPF contributes to oxidative stress, systemic inflammation and metabolic dysfunction - all of which can negatively affect ovarian function and oocyte quality.
At the same time, fertility rates are declining, and the average age of first conception is rising. Given the increasing reliance on UPF, understanding how this diet affects female fertility is crucial for improving fertility outcomes and informing dietary recommendations for women of reproductive age.
what this project aims to achieve
This research fills a critical gap in understanding the impact of UPF. It will highlight the potential female reproductive consequences of these widely consumed foods and bring scientific evidence to this vital conversation.
Our projects will investigate the frequency-dependent effects of UPF consumption on ovarian health. We will assess anti-Mullerian hormone, antral follicle counts, ovarian histology and gene expression.
Our findings will contribute to:
Public health guidelines on dietary
impacts on fertility
Policy changes to regulate
UPF consumption
Raising awareness about the effect of
UPF on reproductive health
Fertility treatments informed by dietary
intervention strategies
Video: The harsh reality of Ultra-processed foods
Join award-winning broadcaster, practising NHS doctor and leading academic Chris van Tulleken as he explores the invention of UPF and its impact on our health and weight – from altering metabolism and appetite to an increased risk of cardiovascular disease and tooth decay.
Research Phase 1
The first step is to complete a systematic review and meta-analysis on ultra-processed food consumption and female fertility. This will involve:
- Searching databases and reviews to find studies looking at UPF and female fertility in the last 20 years.
- Synthesising and analysing the existing data on diet and female fertility.
- Identifying a significant research gap in experimental studies on UPF and ovarian reserve
“As an Olympic athlete, I am expected to be the picture of peak health and performance. Yet, much of my nutrition relies on ultra-processed food, such as protein shakes, cereal bars and energy gels, which has been associated with negative health outcomes. Still, the impact of diets high in UPF on reproductive health are unknown. Which is why it is important to investigate if these widely consumed products are silently harming our fertility.” . - Heidi Long
Research Phase 2
We will then move to experimental lab work. After conducting any necessary pilot studies to refine our methodology, we aim to advance our understanding of how UPF consumption impacts female fertility. Our research will potentially employ multiple complementary approaches, including:
- Mouse model studies: investigating whether the frequency of UPF consumption has an impact on ovarian reserve as a marker of fertility
- Human ovarian tissue culture: assessing how UPF-derived metabolites influence follicle health and reproductive potential
- Glucose and follicle viability: exploring the effects of different glucose concentrations in culture media on follicles in human ovarian tissue
We aim to help bridge the gap between modern dietary patterns and women’s reproductive health outcomes, ultimately contributing to evidence-based fertility recommendations and guidance.
Latest Update: How our research is going
We have just embarked on this exciting research journey, laying the foundation for groundbreaking insights into how ultra-processed food impacts female fertility. UPF is a rapidly emerging topic, and our review has already highlighted critical gaps in experimental research, reinforcing the need for our work.
With many promising collaborations and innovative projects ahead, we are eager to generate original data that could shape future dietary recommendations and influence nutritional policy.
Useful links
The Conversion: Ultra Processed foods
The largest-ever review shows many ill effects on health—how to understand the evidence. Globally, one in five deaths is thought to be due to poor diet, and the role of ultra-processed foods, or UPFs, has attracted much attention in many studies over recent years.
Uk teenagers: Ultra processed foods
Humans have been processing food for thousands of years. While some processing can increase food’s safety and shelf-life, consuming lots of ultra-processed foods (UPFs) is linked to health issues such as obesity, high blood pressure, heart disease and type 2 diabetes.
The harsh reality: Ultra processed foods
We're in a new age of eating, but how is ultra processed food harming our bodies - and the world?
Latest publications
Development of the INDIGO partnership knowledge exchange strategy
Journal article
Taylor Salisbury T. et al, (2026), SSM - Mental Health, 9, 100602 - 100602
Editorial: Post pregnancy contraception
Journal article
Makins A., (2026), Best Practice & Research Clinical Obstetrics & Gynaecology, 105, 102705 - 102705
The research team
Get involved
If you have any questions or would like more information about the project, funding, or grant opportunities, please feel free to reach out to Heidi at heidi.long@lmh.ox.ac.uk. For media enquiries, please contact our communications team at communications@wrh.ac.ox.uk.