What “Cancer-Fighting Foods” Really Mean During Cancer

If you’ve searched online about diet and cancer, or read articles on food, nutrition, and cancer, you’ve probably come across phrases like “cancer-fighting foods” or “superfoods.”

The word “superfood” is often used in marketing, but it doesn’t have a scientific definition. That’s why I prefer to talk about foods of particular interest - foods, or groups of foods, that research shows can support your health and wellbeing during and after treatment.

This blog will help you understand what the research says, and most importantly, how to make sense of it in a way that feels realistic and supportive for you.

What “Cancer-Fighting Foods” Really Means

When people talk about cancer-fighting foods, they’re usually referring to research showing that certain foods contain natural compounds that may help protect cells or support the body’s repair processes.

As the American Institute for Cancer Research explains, many individual vitamins, minerals, and phytochemicals show anti-cancer effects in laboratory studies. This doesn’t mean that eating large amounts of one particular food will bring more benefit. What really makes a difference is variety. By including a wide mix of foods, you give your body access to a greater range of these helpful compounds, so you can tap into more of their potential benefits over time.

I like to think of it as adding more tools to your toolbox. Each food brings something unique, and together, they create a combination that supports your health in more ways than any single food ever could.

These foods are also the ones most often talked about for their anti-inflammatory properties, which we’ll explore more in the next section.

Why Patterns Matter More Than Single Foods

When you start looking into food and cancer, it’s common to see certain foods - blueberries, kale, turmeric, green tea - getting the spotlight. But research consistently shows that what really makes the difference is the overall balance and variety of your diet.

A plant-forward diet pattern is often a good way to think about this. It doesn’t mean eating exclusively plant-based foods. Instead, it’s about giving plant foods - fruits, vegetables, whole grains, beans, lentils, nuts, and seeds - a starring role in your meals, while still including other nourishing foods like fish, eggs, dairy, or lean meats if you enjoy them and they suit your needs.

Here are three key points from current research:

• Plant-forward dietary patterns - similar to a Mediterranean-style way of eating (rich in fibre, colourful plant foods, and beneficial fats) are linked with a lower risk of dying from any cause and, in some cases, a lower chance of cancer coming back.

• Pro-inflammatory dietary patterns - those high in processed meats, refined grains, added sugars, and certain less healthy fats, are associated with less favourable health outcomes.

• The greatest benefit comes from the combination and balance of foods over time, rather than adding one or two “anti-inflammatory” foods or supplements to an otherwise low-quality diet.

There’s still more to learn, and most evidence comes from observational studies rather than clinical trials that prove cause and effect. But what we know so far suggests that variety, balance, and a pattern you can maintain over time are what best support your health and wellbeing.

Understanding Inflammation and Your Diet

Inflammation is often described as a double-edged sword.

• Acute inflammation - the kind that happens after something like a bee sting, an injury, an infection, or a surgical wound - is your body’s natural response. It’s part of the healing process, and your body mounts an appropriate response to help you recover.

• Chronic inflammation is different. It’s when levels of inflammation stay higher for longer than they should. In simple terms, it’s like the body doesn’t quite switch off that inflammatory response. Over time, ongoing low-grade inflammation can be less helpful for your health. Research shows that chronic inflammation is linked to a higher risk of some cancers, as well heart disease, and other chronic conditions. In people living with or beyond cancer, scientists are looking closely at how chronic inflammation might influence cancer growth, progression, or recurrence. While there’s still more to learn, what we do know is that supporting a healthy balance through your diet and other supportive habits, is a strong and positive place to start.

Your diet is one of the ways you can help to support healthier inflammation levels, alongside other parts of your whole-person toolbox - things like movement, sleep, and stress management.

Building in a plant-forward approach, with a wide mix of colourful fruits and vegetables, whole grains, beans, lentils, nuts, seeds, and beneficial fats, can contribute to that healthier balance, and provides nutrients that support your immune system and your overall wellbeing.

Eating this way may also help with some treatment-related side effects, such as fatigue and brain fog - not as a quick fix, but by nourishing your body and supporting it through what can be a demanding time.

This pattern also supports your gut microbiome, the community of bacteria in your digestive system, helping it stay healthy and diverse. Research in this area is growing rapidly, and while there’s still much to learn, we know that a more diverse gut microbiome is linked with a stronger immune response and can have an anti-inflammatory effect. There’s even emerging evidence that a healthy microbiome may influence how well certain treatments, such as immunotherapy, work. It’s an area to keep an eye on as the research continues to grow.

Six Foods of Particular Interest for Cancer Support

Eating well during and after cancer treatment isn’t about strict rules or giving up enjoyment. It’s about finding ways of eating that support your body, help you cope with treatment, build your strength and resilience, and that you enjoy eating.

The foods below come up regularly in research and in practice - not because they’re the only ones that matter, and not in any particular order, but because they can be a helpful starting point for adding variety and nourishment to your meals and snacks.

1. Berries

Blueberries, raspberries, strawberries, and blackberries are naturally rich in antioxidants and fibre. They’re versatile and easy to use - sprinkled over yoghurt, porridge, or overnight oats, blended into smoothies, added to salads, or simply enjoyed as a snack with some nuts and seeds. Fresh and frozen both work well.

2. Cruciferous Vegetables

Broccoli, kale, cabbage, rocket, cauliflower, and Brussels sprouts have been widely studied for their role in protecting cell health. They’re incredibly versatile - roast, steam, or add them to soups, stews, or casseroles.

3. Oily Fish

Salmon, sardines, mackerel, anchovies, herring, and trout are rich in omega-3 fats, which can help support a healthy inflammatory balance and your immune system. They also provide a good source of protein, which is especially valuable during treatment. Tinned fish counts too and is a really useful store-cupboard staple - perfect for a quick and easy meal.

4. Legumes

Beans, lentils, and chickpeas are full of fibre and plant protein. They also provide prebiotic fibres - the kind that feed your gut bacteria and help maintain a healthier, more diverse microbiome. Adding a spoonful to soups, stews, or salads, or blending into a simple hummus, can be an easy way to include them.

5. Nuts and Seeds

Walnuts, almonds, pumpkin seeds, flaxseed, and chia seeds are packed with beneficial fats, protein, and minerals like magnesium. Try a small handful as a snack with fruit, or sprinkled over porridge, yoghurt, or salads.

6. Whole Grains

Foods like rolled oats, brown rice, and barley provide slow-release energy, fibre, and a range of vitamins and minerals. Choosing more whole grains, and fewer highly refined grains, can help support gut health and keep your energy levels steady throughout the day.

Do “Exotic Superfoods” Really Matter More?

There’s a lot of noise around so-called “superfoods”, often driven by marketing or social media, and it’s easy to feel that the more exotic, unusual, or hard-to-find a food is (often the more expensive ones), the more potent or powerful it must be.

But that isn’t the case. Many every day, easy-to-find foods - like apples, carrots, broccoli, or frozen peas - are just as nourishing as anything more unusual. What really matters is the variety and balance of your diet and finding ways to include a mix of foods that work for you - what you enjoy eating, what fits into your life, and your budget.

Why Personalisation Matters

Eating well during and after cancer treatment isn’t a one-size-fits-all approach. There will be times when a plant-forward, variety-rich way of eating feels realistic and enjoyable, and other times when your symptoms, side effects, or energy levels mean that eating looks very different.

If you’re coping with a dry mouth, sore mouth, swallowing difficulties, bowel changes, or spending much of the day in the bathroom, this type of eating approach might be unrealistic, and not what your body needs at a time when simply eating anything at all feels like a victory. In those moments, the focus shifts to getting enough nutrition in a way that works for you. If you’re finding that difficult, I encourage you to seek advice from a dietitian or nutrition professional who can help you find practical, realistic ways to meet your needs.

When I work with people one-to-one in my practice, I look at the whole picture - your treatment, your symptoms, your appetite, your energy levels, and what’s happening in your life. From there, I can see where your focus will make the most difference, and together we turn that into two or three realistic, manageable changes that feel achievable in your day-to-day life.

Nutrition plays an important role, supporting your immune system, helping to manage inflammation, and providing the building blocks your body needs. As I’ve said earlier, it’s just one part of a broader toolbox. Other factors, for example, movement, stress management, good sleep, and emotional support, also make a difference. Not every tool suits every hand, and my role is to help you find what feels right for you, at your pace, without pressure or overwhelm.

Bringing It All Together

Start small. Adding an extra portion of vegetables to a meal, swapping in whole grains, or keeping some nuts and fruit handy for snacks can all be simple, positive steps. Over time, these small changes can build into a way of eating that feels balanced, supportive, and sustainable.

The real power comes from variety. Each food brings its own benefits, but together they create a nourishing environment for healing, repair, and resilience. By combining different types of plant foods, quality proteins, and beneficial fats, you give your body a broad spectrum of nutrients to support your health during treatment and beyond.

I describe this as the symbiotic effect - the way foods and nutrients interact to support your body in ways we simply can’t replicate in a pill. Supplements do have their place and can sometimes be really helpful, but the foundation will always be what you get from a varied, balanced way of eating.

If you’d like help tailoring this to your situation, or if you’re finding it difficult to eat well, do seek personalised nutrition guidance. You don’t need to figure it all out on your own.

Please note: The content provided in this blog is for informational purposes only and should not be considered personalised nutrition, dietetic, or medical advice. Please consult your healthcare team for personalised advice and guidance regarding your specific medical condition or dietary needs.

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