Did you know that a poor diet is thought to be partly responsible for 30 to 40% of all cancers?

However, diet alone is unlikely to be the ’cause’ or ‘cure’ of cancer. Research suggests that exercise, a healthy diet and maintaining healthy body weight, can help reduce the risk of getting breast cancer or of a cancer coming back.

And while some risk factors for breast cancer cannot be modified, such as age and gender, factors such as diet can be improved.

Here are a few foods you should eat to lower your risk of breast cancer:

Eat your greens

In studies mentioned in Diet and breast cancer by Isabelle Romieu, MD, MPH, ScD, it is suggested that fresh vegetables have a protective effect against breast cancer.

A poor diet is thought to be partly responsible for 30 to 40% of all cancers.

According to one case-control study, women who ate greater amounts of cruciferous vegetables (such as cabbage, turnips, broccoli, Brussels sprouts, watercress and cauliflower) had a lower risk of breast cancer.

A high intake of phytoestrogen, an oestrogen-like chemical found in plant foods such as beans, seeds, grains and soya, in adolescent Asian populations is related to lower risk of breast cancer.

Data from Mexico also suggests that high intake of folate and phytoestrogens are related to lower risk.

When it comes to women who have been through menopause, data from Singapore suggests that a diet rich in vegetables, fruit and tofu items has a protective effect against breast cancer.

Data from a large study on French women supports the protective effect of a healthy, Mediterranean eating plan, which essentially consists of vegetables, fruits, seafood, olive oil and sunflower oil.

Go nuts for foods with anti-inflammatory properties

Eating walnuts slowed the development and growth of breast cancer tumours in mice, according to a study published in 2011 in Nutrition and Cancer.

Researchers looked at the effect of a diet containing the human equivalent of 25 to 30 walnut halves a day. After 34 days, mice that ate walnuts had less than half the rate of breast cancer as a control group on the same diet minus the walnuts. The number and size of tumours also were significantly smaller for the walnut group.

Researchers speculate that walnuts’ anti-inflammatory properties are the reason.

While it’s not recommended that this quantity of walnuts is eaten daily, as they have a very high fat content, it’s recommend that one should include foods with anti-inflammatory properties.

Foods with anti-inflammatory properties include kelp, papaya, turmeric, blueberries, broccoli and shiitake mushrooms.

Why eating less meat is a good idea

Recent reports suggest an association between eating red meat and processed meat and the risk of breast cancer.

Eating red meat could increase the risk of breast cancer, because of the highly bioavailable iron content, growth-promoting hormones used in animal production, carcinogenic heterocyclic amines (chemicals formed when meat is cooked at high-temperatures) and its specific fatty acid contents.

To lower your risk, avoid eating processed meats and experiment with some delicious meat-free recipes.

Antioxidants that are anti-cancer

When considering antioxidant intake, there is no consistent association between any antioxidant and breast cancer incidence. However, three studies have suggested a protective effect of vitamin E.

In a Danish study, vitamin E intake has been related to a lower risk of breast cancer among postmenopausal women, and two reports suggest a protective effect of high serum vitamin E on breast cancer risk.

Vitamin B12 boost

There is a suggestion that vitamin B12 may be associated with a lower risk of breast cancer and that low vitamin B12 intake may reduce the apparent protection in the risk for breast cancer conferred by folate.

Fill up on fibre

Fibre could play a role on the risk of breast cancer by decreasing the intestinal re-absorption of oestrogen and therefore lowering its circulating levels.

Vitamin D: The jury is still out

Some studies suggest that the risk of developing certain types of cancer is lower for people who have higher levels of vitamin D in their bodies. There are also studies that suggest higher vitamin D levels might be linked to greater risk of other cancers.

More studies are needed to find out whether vitamin D is the reason for the differences in risk, or if there is another reason. If there is a link, researchers would still have to find out whether vitamin D deficiency raises a person’s cancer risk. They would also need to know whether taking in more vitamin D than the recommended daily allowance changes this risk.

The possible role of vitamin D in treating cancer is still being studied.

Nutrition in early life can affect height and age of a girl’s first menstrual cycle, which are established risks factors for breast cancer. Case-control studies suggest a decreased risk of cancer when the early life diets are high in fat from dairy foods, milk and vitamin D. However, there is an increased risk with high consumption of meat with visible fat.

Dump the junk

Eating foods with a high glycaemic index (foods high in sugar and unhealthy fats) during adolescence is associated with an increased risk of breast cancer.

Data from Mexico also suggests that a high intake of carbohydrate and high glycaemic load is related to an increase of breast cancer.

So what does this mean for you?

Although the results of these studies need to be confirmed in other populations, they suggest that baseline nutritional status and genetic susceptibility might interact with food intake in relation with breast cancer.

In other words, if you want to reduce your risk of breast cancer, pick healthy meals and snacks over greasy take-away meals and vending machine treats!

Recommended reading: Drinking alcohol increases breast cancer risk

For more information about breast cancer and diagnostic procedures, visit www.breastcancerinfo.co.za