Does Milk Raise Cancer Risk?

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Milk, a white colour liquid, which produced by the mammary glands of mammals. Milk is the primary source of nutrition for infant mammals, before they are able to digest other types of food. Early lactation milk contains colostrum, which carries the mother's antibodies to its young, and can reduce the risk of many diseases.

Speaking of colostrum, here's a quote from my previous post:

Is colostrum from cows good for you? Yes, if you are a baby cow…..

Many women think it's not necessary to breastfeed their babies, for at least the first 1½ years. That's why, many children are fat, have allergies, and 'behavior disorders' nowadays. Formula milk will never replace all the substances in a mother’s milk.

Have you wonder why every mammals stops drinking mother's milk at a certain age? It is because by then, their bodies are able to produce itself, its own substances needed for the body, including, hormones, growth factors and other peptides.

Also, have you ever heard a cow gets an osteoporosis? Think again! What does cow eat everyday?

In 2015, according to USDA, world total cows milk production was 491,204 kilo metric tons. While in US alone was 94,480 kilo metric tons. World total cows milk (fluid) consumption was 179,838 kilo metric tons. In US was 26,789 kilo metric tons. And not to mention other diary products, such as, cheese, butter, yoghurt, and ice cream. Most Americans now eat 40% of their calories, in the form of dairy products.

Dairy Products as a Possible Cancers Trigger

A controversial theory singled out dairy products as a possible cancers trigger. Professor Jane Plant, bestselling author of Your Life in Your Hands - Understanding, Preventing and Overcoming Breast Cancer, had made a war against dairy products, started in 1993. Shortly after the doctor told her, that she had only months to live, following her breast cancer recurrences for the 5th time.

Professor Jane, and her husband, Peter, who is also a Professor of Geology, had been worked together in China. Learning that breast cancer rate in China, was one in 100,000 women, compared to a rate of one in ten, in the UK at that time. She then wondered, "Why don't Chinese women in China get breast cancer?" Turned out, it was Chinese women habits, which made them had a lower risk of breast cancer.

Most Chinese people are vegetarian, and to them dairy products are rich people foods. After a year on a strict vegetarian diet, she was being declared cancer free, and remained free of cancer, for nineteen years, without taking medication.

I now believe that, the link between dairy produce, and breast cancer, is similar to, the link between smoking, and lung cancer. - Professor Jane Plant

But still, not everyone who consumed dairy products everyday, die from cancer, and not everyone who smoked everyday, die from lung cancer. Because everyone has a chance of developing cancer, whether they have family history of cancer, or not.

Cancer is an abnormal and uncontrolled growth of the cells that make up living things. Cancer is often thought of as human disease but is actually widespread in most forms of plant and animal life. Tumors have been found in insects, fish, reptiles, birds, fungi, ferns, carrots, spruce, willow, and sugar beets.

Milk Consumption vs. Cancers Risk Study

Reported data of milk consumption habits were obtained by questionnaire, from 3,334 cancer patients, and 1,300 comparable control subjects, at Roswell Park Memorial Institute. As a group, control patients were more likely to report never drinking whole milk. Cancer patients more often reported frequent consumption of whole milk.

The data found that consumption of low fat milk was linked to significant risk reduction for oral, and cervical cancers, but drinking only whole milk was linked to significant risk increases for cancers of the oral cavity, stomach, rectum, lung, and breast. (Mettlin CJ, et al. 1990)

Breast Cancer

Dietary information which based on food frequency questionnaire of 88,691 women was collected from 1980 until May 31, 1996. Among them, there were 3,482 women with incident invasive breast cancer. The study found no association between intake of dairy products, and breast cancer. (Shin MH, et al. 2002)

Recent study among 97 breast cancer patients, and 104 control healthy individuals, in Western Mexico, were analyzed their lifetime consumption of meat and milk. According to the study, high milk consumption increased the breast cancer risk by 7.2 times, whereas the consumption of meat, was not significantly associated with the disease. The study concluded that high consumption of cow's milk was a risk factor for the development of breast cancer. (Galván-Salazar HR, et al. 2015)

Lung Cancer

Cigarette smoking causes most lung cancers. The more cigarettes to smoke per day, and the earlier age of starting to smoke, the greater the risk of getting lung cancer. A prospective case control study, in the west of Sweden, was aimed to investigate the relationship between lung cancer, smoking, and dietary factors.

The study was using the data from the local cancer register, on 308 cases, and 504 controls. The study found no significant risk for males smoking 1-10 cigarettes/day, for less than 20 years. A lower consumption of vegetables was related to a higher risk, both for smokers, and nonsmokers. A higher consumption of milk was related to an increased risk. (Rylander R, et al. 1996)

Ovarian Cancer

Dairy foods and its constituents, lactose and calcium, have been hypothesized to promote ovarian carcinogenesis. Milk is a source of animal fats in the diet, and animal fat intake is associated with ovarian cancer risk.

A case control study of 303 ovarian cancer cases, and 606 age matched nonmalignant disease controls, was performed between 1982 and 1988, at Roswell Park Memorial Institute, in Buffalo, New York. The study suggested that, milk drinking is not a source of ovarian cancer risk independently of its fat content. (Mettlin CJ, et al. 1990)

A case control study in Hawaii, and Los Angeles, California, among 558 ovarian cancer patients, in 1993-1999, and 607 controls, were interviewed regarding their diet. Consumption of all dairy products, all types of milk, low fat milk, but not consumption of whole milk, was significantly inversely related to the odds of ovarian cancer. The study suggested that intake of low fat milk, calcium, or lactose may reduce the risk of ovarian cancer. (Goodman MT, et al. 2002)

A prospective population based cohort study of 61,084 women, aged 38-76 years, who were enrolled, in the Swedish Mammography Cohort. Diet was assessed, in 1987-1990, with the use of a self administered food frequency questionnaire. During a follow up of 13.5 years, 266 women were diagnosed with invasive epithelial ovarian cancer, in which 125 of them had serous ovarian cancer.

The study indicated that high intakes of lactose, and dairy products, particularly milk, are associated with an increased risk of serous ovarian cancer, but no other subtypes of ovarian cancer. (Larsson SC, et al. 2004)

A meta analysis study from 18 case control, and three prospective cohort studies, concluded that prospective cohort studies, but not case control studies, support the hypothesis, that high intakes of dairy foods, and lactose may increase the risk of ovarian cancer. (Larsson SC, et al. 2006)

62,573 postmenopausal women were participating, a self administered questionnaire on dietary habits, and other risk factors for cancer, in the Netherlands. After 11 years of follow up, no association was seen between consumption of milk, yoghurt, cheese, or fermented dairy products, and ovarian cancer risk. The results do not support an association between consumption of dairy products, or lactose intake, and ovarian cancer. (Mommers M, et al. 2006)

A pooled analysis of the primary data from 12 prospective cohort studies was conducted. The study population consisted of 553,217 women, among whom 2,132 epithelial ovarian cases were identified. The study found no associations were observed for intakes of specific dairy foods, or calcium, and ovarian cancer risk. (Genkinger JM, et al. 2006)

Results from epidemiological studies examining the relationship between intake of dairy foods, and breast, or ovarian cancer risk are not consistent. Animal studies have suggested that galactose may be toxic to ovarian cells, but results from epidemiological studies, that have examined ovarian cancer risk, and milk or lactose intakes are mixed. (Rock CL. 2011)

Prostate Cancer

In 1986, 58,279 men aged 55-69 years completed a self administered 150 item food frequency questionnaire. After 6.3 years of follow up, there were 642 prostate cancer cases. Positive trends in risk were found for consumption of cured meat, and milk products. (Schuurman AG, et al. 1999)

A high calcium intake, mainly from dairy products, may increase prostate cancer risk. A cohort study investigated the association between dairy product, calcium intakes, and prostate cancer risk, in the Physicians's Health Study, a cohort of male US physicians.

During 11 years of follow up, the study documented 1,012 incident cases of prostate cancer, among 20,885 men. The study resulted that, men consuming dairy products >600 mg/d, had a 32% higher risk of prostate cancer. The study supported the hypothesis, that dairy products, and calcium are associated with a greater risk of prostate cancer. (Chan JM, et al. 2001)

Multiethnic cohort study, from 1993 to 2002, was aimed to examined 82,483 men who completed a food frequency questionnaire. During a follow up of 8 years, 4,404 total cases of prostate cancer were identified. The study suggested an association between milk consumption, and prostate cancer risk may vary by fat content, particularly for early forms of this cancer. (Park SY, et al. 2007)

Tell me what you eat, and I will tell you what you are! - Jean Anthelme Brillat-Savarin