Food sits right at the intersection of human health and environmental sustainability, making it both a challenge and an opportunity. In the UK, the Eatwell Guide already offers a clear, evidence‑based picture of what a healthy dietary pattern looks like. However, its primary lens is health. As the science on planetary boundaries and food‑related emissions has strengthened, there is a growing case for updating the Eatwell Guide so that environmental sustainability is not an add‑on, but built into the model itself. That would mean making plant‑rich eating the default, clarifying how much and what kinds of animal‑source foods fit within a climate‑compatible diet, and signalling the importance of issues such as food waste and environmental impact from manufacturing and transport. In practice, this would help align everyday dietary advice with the UK’s wider climate and nature commitments, while still protecting nutritional adequacy across the life course.
At King’s College London, this intersection is exactly where much of our work now sits. The newly formed FoLSM Research Interest Group – Safe and SUstainable Diets for a healthy body and mind (SSuDs) – originating from within the Department of Nutritional Sciences, brings together nutritional sciences, clinical practice, population health, behaviour change and food systems research to ask a simple question: how do we shift diets in ways that are good for the planet, and help in the prevention and management of disease?
Because this is where things get complicated.
Why “eat less meat” isn’t the whole story
While some alternative livestock practices may lower emissions (e.g., methane-reducing feed additives such as seaweed supplements, and some pasture diversification approaches), their effectiveness and scalability vary, and many remain limited in implementation. Given these uncertainties and the time needed to scale proven options, most Net Zero pathways still rely on reductions in ruminant meat consumption.
Calls to reduce meat consumption have become more prominent: from policy reports, social media (Veganuary), public sector initiatives (meat-free Mondays), to supermarket shelves. But while reducing meat is necessary for climate goals and may help to reduce some health risks such as high blood cholesterol, the jury is out on whether the benefits outweigh the risks.
Red meat, for all its environmental cost, is also a rich source of nutrients such as iron, vitamin B12 and high-quality protein. This matters particularly for women of reproductive age, who already face a high global burden of iron deficiency. If dietary shifts are not carefully designed, there is a real risk that well-intentioned climate action could unintentionally worsen health inequalities.
This tension between environmental urgency and nutritional safety is one of the biggest uncertainties holding policy back. We know what needs to change, but we are still generating evidence on how to do it safely at population level.
That uncertainty is a core focus of our current research. Rather than debating whether meat reduction is needed, we ask: which meat-alternative pathways work best, for whom, and under what conditions? Whole plant foods? Plant-based meat alternatives? Insects? Or combinations of these? How can we better optimise plant-based diets? And what are the real health implications over time?
From campus plates to living laboratories
One of the most exciting aspects of being a researcher at King’s is that these questions don’t live only in academic journals; they’re being explored right here on campus.
Through close collaboration with King’s Food, we are helping to turn everyday food environments into living laboratories. Initiatives such as root-to-tip cooking, waste reduction and plant-forward menus allow us to test how sustainable choices can be made attractive, affordable and normal.
At the same time, King’s Climate & Sustainability seed funding has enabled more exploratory work, including research into insects as sustainable protein sources. While insects won’t appear on everyone’s plate tomorrow, they hold promise as food ingredients to add additional protein or micronutrients (vitamin B12, iron, calcium) and may in future open up new options for feeding a growing population with a smaller environmental footprint.
People first: diets that work in real life
A recurring lesson from our work is that dietary change isn’t just about nutrients or emissions. Cost, convenience, culture, family life, identity and trust all shape what ends up on the plate. Working with communities, students, and public contributors to ensure that sustainable dietary guidance is realistic and inclusive is essential for meaningful change. If guidelines only work for the already motivated, they won’t deliver the change we need.
This also means being honest about trade-offs, uncertainties and risks. Sustainable diets are not a finished product; they are evolving and only a few countries currently position sustainability front and centre of their dietary guidelines. To accelerate adoption, we need evidence-led solutions that must balance climate goals with health, equity and feasibility.
Why this moment matters
The climate challenge won’t wait, but neither should we rush dietary advice without the evidence to support it. Right now, globally and in the UK, decisions are being made about the future of food; what we grow, what we subsidise, what we recommend, and what we normalise.
The work underway at King’s aims to help ensure those decisions are grounded in robust science and realism. If we get this right, food becomes one of the most powerful tools we have for positive change.
(1) EAT-Lancet Commission London Launch