11 Myths about Breast Cancer – Does Dairy Food Cause Breast Cancer?

There is a misconception between soy products and breast cancer. Rumour has it that soy has a chemical structure like an estrogen, so eating soy will affect hormones and cause breast cancer.

The fact is, soybean is the main source of isoflavone, a type of phytoestrogen (plant compound). It is considered chemoprotective and helps in several hormone disorders, including breast cancer, prostate cancer, or menopause symptoms. (1)

It is found that Asian women, who have a high consumption of soy products, have lower breast cancer risk than the low soy consumption in Western countries women. (2), (3)

There is no scientific evidence that breast size affects the risk of breast cancer.

However, mammographic density, or “breast density” has been shown as one of the risks. Breast are regarded as dense if they have a relatively high amount of connective and glandular tissues and less fat. (4)

Breast density is often determined by genetics.

The logic of this belief works like this: Wearing bra restricts lymph circulation, thus blocking toxin and waste removal.

However, this statement is not backed with evidence. A study in 2014, on thousands of postmenopausal women, found no evidence that bra-wearing is related to any breast cancer. (5)

Some said to avoid the underwire bra and choose those without wire, this is also untrue. You can choose whatever that you are comfortable with. 

While genetics strongly heightened the perceived risk (especially from the maternal side), majority of patients are diagnosed without any family history of breast cancer.

According to a study involving 6706 of different ages women, hereditary breast cancer only account for approximately 15% to 20% of all cases.

The rest patients have no family history of breast cancer and are affected by other factors like the environment and lifestyle. (6)

It is true that the risk of breast cancer increases with age, commonly over the age of 50 years old. (7) However, this does not mean younger women are excluded.

A study from Malaysia shows 16.8% of women were diagnosed below 40 years old, and 2% were under 30. (8)

Besides, younger patients tend to have more aggressive cancer cells,  and are more likely to have cancer recurrence. (9) It cannot be taken lightly. 

Women take contraceptive pills for several purposes like birth control and other hormone-related problems such as acne and heavy period. (10)

However, it become a concern that the birth control pill can trigger cancer cells, as they are mainly composed of hormones - estrogen and progesterone.

A lot of studies have been done on this topic, but the result is inconsistent. More research stated taking hormonal pills is linked to a slightly higher risk of breast cancer.  (11), (12), (13), (14)

While some suggested that the newer form of contraceptive pill is much safer than the old form as the hormone used is lower.
(14), (15)

To play safe, You should talk to your doctor before taking pills. Consider your age, health condition, if you have any other high risk factors of breast cancer, benefit and risk of taking or not taking the pill.

This is not true. Even though women have a much higher chance of getting it, men are not totally excluded from this disease.

For example, in United State, 1 out of 100 breast cancer diagnosed is found in a man. (16)

Many are afraid of drinking milk because they assume the cows are injected with hormones, by drinking milk the hormone will accumulate in the body.

On this issue, a study shows that the daily intake of estrogen from dairy products is very insignificant in comparison to the daily estrogen secretion from humans themselves. Besides, the study also stated cow’s growth hormone is biologically inactive in humans. (17)

However, it is important to note that frequent consumption of high-fat dairy products might contribute to an increased risk of breast cancer, regardless if total energy intake is controlled or not. (18)

Again, moderation is the key.

Consider taking low-fat dairy products like yoghurt and low-fat milk to reduce saturated fat intake. (19)

Females are encouraged to do a breast self-examination (BSE) for breast cancer awareness.
 
However, do not panic if you detect a lump in your breast, it can be harmless. The next step is to book an appointment with GP to have a further examination.

On the contrary, not all breast cancer comes with a lump.(20)

It is advisable to do a regular screening, especially when the age goes older. 

“Sugar feed cancer cell so don’t eat sugar”.

Indeed, sugar feed cancer cell, but it feeds normal body cells too. Simply omitting carbohydrates from the diet might cause malnutrition or lack of proper nutrition in patients.
 
A study from Malaysia showed no evidence that sugar causes breast cancer. (21)

However, a high level of insulin-like growth factor 1 (IGF1) and hyperinsulinemia (high level of insulin in the blood) is associated with several cancers including breast cancer. (22), (23)

Thus, it is always a good idea to reduce refined sugar intake, like desserts, sweetened beverages and other sweet processed food.  Instead, focus more on consuming high-fibre carbohydrate food like cereal and certain vegetables.

We know that many merchants use “breast cancer prevention” as a gimmick to promote their products. As we know some vitamins do help to lower cancer risk, but they can’t guarantee you will not get the disease.

Even someone who maintains an extremely healthy lifestyle has a chance to get breast cancer, not to mention those who only rely on healthcare products. (24)