The Benefits of a balanced diet during breast cancer treatment

26 Jun 2023

Preparing for breast cancer treatment, you may feel overwhelmed, apprehensive and uncertain. And that’s completely understandable and to be expected. At times like this, you naturally look to areas you can control to retain a sense of balance and power.

What you eat and when is one of those areas. However, you mustn’t place additional pressure on yourself regarding what to eat during treatment.

You may be tempted to jump online to research “What to eat during chemotherapy?” or “What food should be avoided during breast cancer treatment?” Unfortunately, you may cause yourself more confusion and anxiety, which is far from ideal.

Caley Schnaid, an Accredited Practising Dietitian specialising as an Oncology Dietitian, recommends that you “focus on eating as well as you can, and stick with what you can manage if you find you tolerate some foods better than others during treatment”.

Caley suggests doing your best to follow a balanced, whole-food diet during treatment with increased protein, similar to the Mediterranean Diet. This includes eating a variety of fruits, vegetables, whole grains, beans, nuts, legumes, lean proteins, good fats from olive oil, and dairy.

However, Caley is also mindful that any radical change in eating habits can be unrealistic and will likely add additional stress during cancer treatment. So, it is more important to do the best that you can and seek personalised support from your doctors and a dietitian specialising in cancer care if needed.

To help you prepare for treatment and to remove some of the overwhelm, we asked Caley for her advice on the following common concerns.

Loss of Appetite

A loss of appetite may be experienced during cancer treatment, specifically chemotherapy. To ensure you make the small amounts that you do eat as nutritious as possible, Caley recommends fortifying all snacks and small meals with protein and nutrient-dense choices. For example, porridge made with whole milk, not water, and the addition of nuts and seeds, such as chia seeds. Apple slices with nut butter or vegetable sticks and hommus dip.


Keep fluids high by drinking; on average, 2L of water per day is essential for flushing the toxins from chemotherapy and transporting nutrients from your food into the bloodstream.

Food Safety

Pay attention to general food hygiene and food safety measures, such as washing your hands before preparing and handling food. Always check and be aware of food expiration and use-by dates. Avoid buying and eating food from open delis. Avoid eating raw fish, eggs and chicken. And Caley also likes to remind patients this includes sushi.

Should you remove dairy and antioxidants during chemo?

A common concern that Caley encounters is when dairy has been removed from a diet during chemo, unrelated to allergy. There is no evidence to suggest that it is necessary to cut out dairy. Caley considers dairy an essential dietary element, particularly for breast cancer patients. Dairy is a primary source of calcium and a high source of protein, both of which are important during breast cancer treatments.

Caley advises no need to remove antioxidant-containing foods from your diet during treatment. However, it is recommended not to take any mega-dose antioxidant supplements due to interactions with cancer cells and the possibility of lessening the impact of the chemotherapy.

Preparing Meals in Advance

Caley recommends planning for the days when you won’t feel like cooking by using the time leading up to your treatment to batch-cook nutritious meals such as stews and soups that can be frozen. Having these meals on hand to quickly reheat and eat with little effort will mean nourishment and energy on the days you most need it.

Keep Easy To Access Nutrition on Hand

One of the simplest things you can do is ensure you always have easy access to simple but nutritious food. Caley suggests keeping stock of foods that you can just open and eat like yoghurts in the fridge, and choosing brands fortified with protein, tins of baked beans in the pantry, individual tubs of hommus and pre-cut vege sticks or cheese and biscuit snack packs.


Even though this article is about nutrition and what to eat, Caley wanted to stress the importance of continuing to exercise. She explains that “Diet and exercise go hand in hand. Both are required to maintain muscle to the highest level you can during treatment, without exhausting yourself.”

Exercise is safe for cancer patients, and research shows treatment can be tolerated better by those who maintain regular exercise routines. However, always seek advice from your doctor first.

Most importantly, Caley wants every cancer patient to understand that they may not have complete control over their body weight during treatment as this may be affected by factors beyond their control.

It is more important to focus on being the healthiest version of yourself that you can be at this stressful time. You can do this by eating well, exercising regularly and looking after your overall well-being.

Read our blog about how to find an Oncology Dietitian, and you may also find our blog on the psychological impacts of a cancer diagnosis helpful.

This article has been reviewed by Caley Schnaid, an Accredited Practising Dietitian (APD) and Accredited Nutritionist (AN) in Australia.

This content is brought to you in partnership with Eli Lilly Australia and developed independently by the team at Pink Hope in consultation with medical experts.