Nutrition and Supplements in Breast Cancer Care

Mun-Yee Chik

Nutrition and Supplements in Breast Cancer Care

There are many factors that influence the development of cancer. In the past 25 years, science has shown that diet, physical activity, and being overweight are major risk factors for developing certain types of cancer. Genetics do play a role but 80% of cancer risk actually come from our environment – that is, how we live our lives through our diet and lifestyle choices, as well as our exposure to pollutants. Studies have shown that our body’s ability to resist cancer can be enhanced by adopting a healthy diet, staying physically active, and avoiding excess body fat.

So let’s go through some commonly asked questions about diet, nutrition and cancer.

Should I eat only organically grown foods?

The term “organic” is defined as foods grown on contaminant-free land without pesticides or herbicides. Eating foods that contain pesticides could increase cancer risk slightly. But even if you don’t eat organic produce, eating conventionally-grown produce is far better than not eating fruits and vegetables at all. This is because consuming a diet rich in fruits and vegetables, whether grown conventionally or organically, is an important part of a diet that lowers overall cancer risk. Whether conventional or organic, it important we rinse the vegetables and fruits properly before consuming. If you decide to purchase organic produce, information from the Environmental Working Group (EWG) may be helpful to those who are living in the US. The EWG has listed non-organic fruits and vegetables with the highest amount of pesticides (“dirty dozen plus two”) and the non-organic fruits and vegetables with the least amount of pesticides (“clean fifteen”). This guide is available at their website at Bear in mind that this guide is done for the USA, so may not be relevant for other countries in terms farming practices and soil nutrients. Also, remember that organic cookies, chips, and other snacks can contain exactly the same amount of calories, fat, and sugar as non-organic brands and are not necessarily healthy just because they are organic.

Juicing: Is It Okay to Juice During Cancer Treatment?

Juicing can be a great way to add a variety of fruit and vegetables and naturally occurring phytochemicals to the diet.
However, relying only on juices for nutrition while undergoing or recovering from cancer treatment is not recommended. Cancer survivors should eat a diet containing enough protein and calories for maintaining body weight during cancer treatment. From a Chinese Medicine perspective, simply relying on juicing is not encouraged during winter months as it will not be sufficient to provide energy & warmth for the body’s nourishment.

If you are juicing, remember to thoroughly wash all fruits and vegetables before adding them to the juicer.

Does Following a Vegan or Vegetarian Diet Reduce the Risk of Cancer and its Recurrence?

A vegetarian diet may be a healthier alternative to a typical meat-heavy diet in general. If you are not currently a vegan however, I would not recommend adopting a vegan diet during active cancer treatment, unless under supervision by a qualified dietician or nutritionist. Instead, I highly recommend a mostly plant-based diet containing small amounts of animal protein. This meal plan should include a variety of foods including many different colourful vegetables and fruits, whole grains, plant proteins such as beans and tofu as well as some meat.

Can Women with Breast Cancer Eat Soy or Soy-Containing Foods?

There is a lot of conflicting advice on soy foods and products among many health practitioners, mainly concerning soy as phyto-oestrogens. Soy foods contain isoflavones, which are phyto-oestrogens that in some ways mimic the action of oestrogen but are very weak. Because high levels of oestrogen is linked to increased breast cancer risk, some fear that soy foods could increase that risk. Yet overall, human studies show soy foods do not increase breast cancer risk and, in some cases, research suggests soy may lower risk. Additionally, population studies do not show any harmful interactions between soy foods and anti-oestrogen medications for breast cancer survivors.

I do however, recommend that women diagnosed with breast cancer avoid soy or phyto-oestrogen supplements, or a sudden increase in their dietary intake of soy or phyto-oestrogen. If you’re a vegetarian who relies on soy products as your protein source, I suggest focusing on whole soy products which are less processed (and organic where possible) e.g. whole soybeans or edamame, tofu, non-sweetened soy yoghurt and fermented soybeans like tempeh, natto or miso. Highly processed soy foods and snacks should be avoided.

Should I avoid eating red meat?

There is evidence that eating red meat, especially processed meat (cured with the addition of preservatives and/or other additives) is linked with an increased risk of bowel or colon cancer. Despite some concerns about meat and cancer, lean red meat is an important source of dietary iron, zinc, vitamin B12 and protein.

If you are not a vegan/vegetarian, I recommend a mostly plant-based diet along with about 100g of cooked red meat no more 3 times a week. One way of eating less meat is cutting your meat into small pieces to be stir-fried with lots of vegetables or in salads, stews or curries, instead of having steaks. Limit consumption of processed meats (e.g.salami, bacon and ham) which are typically high in fat and salt. Also avoid barbequed meats as substances formed in foods cooked at high temperatures that become blackened or charred can increase risk of cancer.

Does sugar feed cancer and should I cut sugar out completely?

The belief that sugar in the diet somehow “feeds” cancer is very common, but the truth is more complicated. All cells, including cancer cells, in the body use sugar (or glucose in its simplest form) from the bloodstream for fuel. Carbohydrates from foods like fruits, vegetables, whole grains, and dairy products get broken down into glucose as primary fuel for our bodies and our brains. When there is not enough carbohydrate in the diet, glucose will have to be produced by the body from protein-containing foods through a special process.

Because fruits and most vegetables contain different levels of sugars in them, there is really no such thing as a “sugar-free” diet. Among the vegetables that are high in sugar are carrots, zucchini, beetroot, turnip; pepper and capsicum,

onions and starchy vegetables like peas, pumpkin, potatoes and corn. And oh, nuts like almonds, hazelnuts and walnuts contain sugars as well. So what we want to avoid are highly processed or added sugars in our diet. High-sugar foods mean more calories which can lead to excess weight and body fat. It is excess body fat that has been linked to greater risk of several types of cancer, including breast cancer. Highly refined foods and foods with added sugars, such as sugary drinks and sweets, are also low in fibre and low in nutrients. So they add little to the diet except empty calories. These foods may also increase insulin resistance, and this has been linked to an increased risk of developing diabetes, heart disease and obesity.

Is it ok to drink alcohol?

A 2007 Women’s Health Study found that moderate alcohol consumption increases breast cancer risk in hormone-sensitive tumours. Consuming three to four alcoholic drinks per week after a breast cancer diagnosis may increase the risk of breast cancer recurrence, particularly among postmenopausal and overweight women. I highly recommend that women with breast cancer to avoid drinking alcohol, because there is no safe level. If alcohol is included in your diet, then I suggest that you drink no more than two standard alcoholic drinks a week. Remember, one ‘standard drink’ contains about 10 grams of alcohol, which is about 100 ml of wine. A general rule of thumb is the purer the alcohol, the healthier it is for you. That means that single-ingredient alcohols, like 100% agave tequila or wine made just from grapes (with no sugars or sulfites added) are generally better for you than alcohol that comes from several ingredients such as cocktails or mixers.

What supplements should I take or avoid during cancer treatment?

Dietary supplements should not replace nutrient-rich foods in our diet. Some dietary supplements can make the skin sensitive, causing severe skin reaction during radiation therapy. Some herbs can make chemo drugs less effective or cause side effects such as bleeding. Antioxidants may stop conventional cancer treatments from killing cancer cells.

During active cancer treatment like chemotherapy or radiotherapy, it is important that any dietary supplement intake be supervised by a qualified cancer health professional. In certain cases such as iron-deficiency anaemia or osteoporosis, dietary supplementation may be recommended for you by your healthcare team.

Safe dietary supplements during cancer treatment.

Ginger is an herb that may help with nausea and vomiting from chemotherapy, along with drugs that prevent or treat nausea and vomiting. Ginger is available in capsules, fresh as a root, in tea, or in candy.

Ginger is an herb that may help with nausea and vomiting from chemotherapy, along with drugs that prevent or treat nausea and vomiting. Ginger is available in capsules, fresh as a root, in tea, or in candy.
Lactobacillus is one of the main types of friendly bacteria in probiotics. It may be effective for preventing diarrhea due to chemo drug 5-fluorouracil or 5-FU. Lactobacillus is in some fermented foods like yogurt and in dietary

To Learn More Book an Appointment at My OncoThrive!

Latest Articles

View All Articles

Supporting Your Loved One Through Their Cancer Journey

Cancer is stressful, not just for the person receiving the diagnosis, but for those around them too. It’s common for family and friends to feel scared, confused, and overwhelmed. Even if you’re not the one with cancer, your emotions are valid. Cancer can be difficult for everyone.

How to adopt a resilient mindset throughout your cancer journey

Studies find that adopting a resilient mindset can help cancer patients cope better, not just through their cancer journey, but also in recovery.