What is the best diet for cancer patients?

Cancer affects everyone differently. Following diagnosis, it might be hard to eat because you are worried and upset. Or the type of cancer you are facing could impact your appetite or ability to eat. Cancer treatment can also have gastrointestinal side effects like constipation, diarrhoea, nausea and loss of taste that can all make eating challenging. Meanwhile, some medications can make you hungrier than normal.

As your appetite is likely to fluctuate, it can be harder to maintain a healthy weight. So it’s important to eat when you can and want to. It can sometimes help to eat a little but often, rather than three set meals a day.

Unless your medical team advises otherwise, there isn’t a specific diet for young people with cancer to stick to. But a nutritious and balanced diet is important, as it is for everyone.

A healthy diet for cancer patients can help in many ways. It has the potential to boost your energy levels, support your immune system, reduce inflammation and help to manage treatment side effects.

But when you’re feeling unwell, what matters the most is that you’re eating something. If you only fancy certain foods, that’s okay. You need food to build strength and every small bite helps.

Ideally, though, your meals throughout the day should include something from each of the main food groups below. This doesn’t mean you need to stop eating all the foods you love - and, remember, healthy meals should be tasty too. They don’t need to be complicated, either.

Fruit and veg

Wherever possible, try to have five portions of fruit and veg a day in various colours. These are full of vitamins, minerals and fibre. And fruits like avocados also contain healthy fats which can potentially help to limit inflammation in illnesses including cancer (more on that below).

Proteins

Healthy proteins include eggs, fish, lean meats and soya. This food group also covers plant-based proteins such as beans, nuts and pulses, which can be some of the richest in vitamins and minerals. Aim to have a source of protein two to three times a day.

Carbohydrates

This food group covers things like oats, pasta, rice and bread, and it’s great for giving us energy. Choosing whole-grain options is best, as they go through the least processing before reaching your plate and contain lots of digestion-boosting fibre. Try to have some carbs with each meal.

Dairy and alternatives

Dairy products like milk, yoghurt and cheese contain nutrients like protein and calcium, which are important for many reasons including bone growth. If you are allergic to dairy or prefer alternative products like almond milk then double-check that they are enriched with calcium. A portion of dairy or alternatives, like a 200ml glass of milk - two to three times a day - form part of a balanced diet for cancer patients.

When you have cancer, it’s sensible to limit certain foods. This includes things like high-fat takeaways and food that’s been heavily processed, like hot dogs, frozen pizza, sweets and sugary drinks.

This is because these foods tend to be high in fat, sugar and salt - and lower in the nutrients that form part of a healthy, balanced diet. People without cancer, and those in recovery or remission, are also advised by the NHS to limit these foods in their diet.

If your immune system is weakened by cancer, your doctor might also recommend avoiding some raw foods like sushi and shellfish, undercooked meats and meals containing raw eggs. There is a higher risk of foodborne illnesses in these foods, which can make people with compromised immune systems very sick.

You may read or hear about the impact of anti-inflammatory foods on cancer. But what does this mean? Inflammatory foods are generally considered to be heavily processed, fried or high in unhealthy fats. During cancer, inflammation happens in various parts of our bodies and so eating high levels of these foods will not help to reduce or control it.

Foods that can potentially help to fight inflammation include many nutritious foods from the four main food groups. Both a healthy diet and an anti-inflammatory diet include plenty of lean protein, healthy fats, whole grains and vitamins and minerals. Reducing meat intake and eating more fish and pulses can also be potentially beneficial in helping to reduce inflammation.

Eating the kind of nutritious food we’ve spoken about above is best, whether you’re going through cancer treatment or not. But there may be times when you will find it difficult to eat during chemotherapy because you feel sick or too tired.

When this happens, the most important thing is to eat whatever you can manage.

The potential side effects of chemotherapy, like a sore throat or mouth ulcers, can also make it hard to eat. Meals for chemo patients with these symptoms should not consist of rough foods like toast and crisps but include soft foods that need less chewing. Even an ice lolly or some frozen fruit will help to give you energy and could soothe soreness in the mouth and throat.

Smoothies and soups or broths are some of the best foods to eat while on chemotherapy, or when other cancer treatments reduce your appetite or ability to eat. These can combine your favourite fruit or veg and will help to get vital nutrients into your body.

Other meal ideas for chemotherapy treatment

Light and simple meals for chemo patients are usually best, such as:

• baked beans on toast with grated cheese
• jacket potatoes with fillings like tuna and sweetcorn
• pancakes topped with honey, fruit and yoghurt
• omelettes with cheese and your favourite veg
• carrot sticks and hummus 
• crumpets topped with jam, marmite or melted cheese
• sardines on soft, buttered toast
• pineapple tacos
• poached egg and avocado
• porridge topped with fruit
• sweet potatoes and vegetables baked with feta cheese
• chopped bananas and peanut butter
• tuna and caper pasta salad

Taking food supplements when you have cancer, especially if you’re struggling to eat, can be beneficial. But you need to ask for your doctor’s advice first.

Even if you are finding it hard to eat, it’s important that you drink plenty of water - even if it’s taking small sips regularly throughout the day. Aim to drink between six to eight 250ml glasses of water if you can. The best way to tell if you’re drinking enough is the colour of your pee; it should be pale yellow, and if you’re not having enough water it will be dark yellow and strong.

Milk, sugar-free squash and hot drinks all help to maintain your fluid intake, too. Freshly squeezed fruit juices like fresh orange juice can also help, and count towards your one-a-day.