Is a vegan diet safe during cancer treatment?

A vegan diet is safe during cancer treatment. However, there is no evidence that a strict vegan diet provides any advantages.

There is some evidence that eating foods containing soy and fibre may reduce the risk of breast cancer recurrence.

What does the term ‘vegan’ mean?

A vegan diet does not contain any animal products (or any animal-derived ingredients) such as meat, fish, dairy products, eggs and honey.

Coping and eating well during treatment

If you want to follow a vegan diet, it’s much easier to follow a vegan diet if you are feeling well during your treatment, so getting the support needed during treatment is key.

Struggling with symptoms and side effects?

People should not be afraid to buy vegan convenience foods and ready meals to get them through. The most important thing is to get enough energy and protein to meet needs during treatment.

Vegan sources of protein

During treatment, consuming enough protein is important, and ideally at each meal. Vegan protein sources include food such as lentils, soya products (like soya mince), tofu, some plant-based milks (like soya milk), beans, nuts and seeds. Vegan protein powders (like pea or rice protein) are also available and can be added to soups, stews, and smoothies to boost your protein intake.

Adding extra energy

Oils (such as olive and rapeseed), avocados, nut butters (such as almond), coconut milk and coconut cream are good sources of vegan energy-dense (high in calorie) foods. Adding oils to soups and stews, adding nut butters to smoothies or cereals, or sprinkling crushed nuts on top of cereal or yoghurt is a great way to boost the energy content of meals and snacks.

Important nutrients

There are some important nutrients to consider if someone follows a vegan diet, these include:

  • Vitamin B12
  • Protein
  • Omega 3
  • Calcium
  • Iron
  • Vitamin D
  • Iodine
  • Zinc

For many nutrients, you may need to consider a vitamin and mineral supplement that is suitable for vegans. However, you should check with your oncologist or pharmacist that it’s suitable for the treatment you are having (high dose vitamin and mineral supplements are not recommended and may impact on your treatment).

Many vegan foods are fortified with important nutrients (like vitamin D), so it’s a good idea to check the label.

Some people may struggle with certain aspects of a vegan diet after some cancer treatments and/or surgery. If you are planning on trying to go vegan, always consult your oncology dietitian first.

> For more information and advice about going vegan, visit the Vegan Society

> Read our blog: could soy products affect my risk of cancer?

> Find out: can a vegan diet inhibit cancer growth?

In association with

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