A st
udy published in early 2001 in the journal Cancer Epidemiology, Biomarkers & Prevention suggests that eating a Western diet can potentially increase the risk of breast cancer in postmenopausal women by increasing the bioavailability of sex hormones which are known to promote the growth and progression of breast cancer.
Franco Berrino from Istituto Nazionale Tumori in Milan, Italy and colleagues conducted the study and found an ad libitum diet which was low in animal fat and refined carbohydrates such as cane sugar and high fructose corn syrup and high in low-glycemic index foods, monounsaturated and omega-3 polyunsaturated fat and phytoestrogens such as those found in soy foods modified sex hormone profiles favorably in postmenopausal women.
According to the study report, Western diet can affect the bioavailability of sex hormones and high serum levels and testosterone and estradiol are known to be important risk factors for breast cancer in postmenopausal women.
For the study, 104 postmenopausal women selected from 312 volunteers because they had high serum testosterone levels were randomized to dietary intervention or control. T hose who were subject to the dietary intervention were given intensive dietary counseling and offered specially prepared meals twice a week for 4.5 months. The changes in serum testosterone, estradiol and sex hormone binding globulin were monitored before and after intervention. Controls did not receive any counseling.
As a result, women in the study group increased the serum sex hormone-binding globulin level significantly, compared with those in the control group, 25% versus 4%. On the other hand, those in the study group also decreased serum testosterone compared with those in the control group, -20% versus -7%. Estradiol levels were also found lower in the study group compared with those in the control group.
In addition, the dietary intervention group significantly reduced body weight compared with controls, 4.06 kg versus 0.54 kg.
A special dietary modification in diet designed to lower insulin resistance and increase intake of phytoestrogen was found to decrease the bioavailability of serum sex hormones in the postmenopausal women with high sex testosterone levels.
Because high sex hormones are associated with increased risk of breast cancer, the study suggests that using the modified diet introduced in the study instead of the typical Western diet may help reduce the risk of breast cancer in postmenopausal women, particularly those with high testosterone levels.
Dietary fat, particularly saturated fat which is found high in meats linked to increased risk of breast cancer. Fat can boost the production of cancer-promoting sex hormones
udy published in early 2001 in the journal Cancer Epidemiology, Biomarkers & Prevention suggests that eating a Western diet can potentially increase the risk of breast cancer in postmenopausal women by increasing the bioavailability of sex hormones which are known to promote the growth and progression of breast cancer.Franco Berrino from Istituto Nazionale Tumori in Milan, Italy and colleagues conducted the study and found an ad libitum diet which was low in animal fat and refined carbohydrates such as cane sugar and high fructose corn syrup and high in low-glycemic index foods, monounsaturated and omega-3 polyunsaturated fat and phytoestrogens such as those found in soy foods modified sex hormone profiles favorably in postmenopausal women.
According to the study report, Western diet can affect the bioavailability of sex hormones and high serum levels and testosterone and estradiol are known to be important risk factors for breast cancer in postmenopausal women.
For the study, 104 postmenopausal women selected from 312 volunteers because they had high serum testosterone levels were randomized to dietary intervention or control. T hose who were subject to the dietary intervention were given intensive dietary counseling and offered specially prepared meals twice a week for 4.5 months. The changes in serum testosterone, estradiol and sex hormone binding globulin were monitored before and after intervention. Controls did not receive any counseling.
As a result, women in the study group increased the serum sex hormone-binding globulin level significantly, compared with those in the control group, 25% versus 4%. On the other hand, those in the study group also decreased serum testosterone compared with those in the control group, -20% versus -7%. Estradiol levels were also found lower in the study group compared with those in the control group.
In addition, the dietary intervention group significantly reduced body weight compared with controls, 4.06 kg versus 0.54 kg.
A special dietary modification in diet designed to lower insulin resistance and increase intake of phytoestrogen was found to decrease the bioavailability of serum sex hormones in the postmenopausal women with high sex testosterone levels.
Because high sex hormones are associated with increased risk of breast cancer, the study suggests that using the modified diet introduced in the study instead of the typical Western diet may help reduce the risk of breast cancer in postmenopausal women, particularly those with high testosterone levels.
Dietary fat, particularly saturated fat which is found high in meats linked to increased risk of breast cancer. Fat can boost the production of cancer-promoting sex hormones
One thing in the Western diet that may boost the risk of breast cancer is fat. A review published in Journal of the National Cancer Institute shows that dietary fat reduction can lower the serum level of estradiol by 7.4% in premenopausal women and 24% in postmenopausal women.
Anna H. Wu, Ph.D., University of Southern California/Norris Comprehensive Cancer Center in Los Angeles, CA and colleagues meta-analyzed the data from 13 studies on estrogen/estradiol and dietary fat intervention published from Jan 1966 through 1998 and found the association.
More significant reduction in sex hormones was found in two studies in which the dietary fat was reduced to 10 to 12% of total calories. T he American Dietary Guidelines recommends that the dietary fat should not exceed 30%, which some nutritionists have said are too high.
The authors reviewed prospective analytic epidemiologic studies and found evidence suggesting “that the possibility that reducing fat consumption below 20% of calories will reduce breast cancer risk cannot be excluded.”
High sugar in the Western diet can also contribute to the high risk of breast cancer in the West
It is not just high fat in Western diet that may increase the risk of breast cancer. Studies indicate that high sugar in the Western diet can also increase the risk of breast cancer, particularly in those postmenopausal women.
Stephen Seely from University of Manchester Medical School in Manchester, England and colleagues proposed in Medical Hypotheses in 1983 that high sugar in the Western diet may also be responsible for some cases of breast cancer.
The authors reviewed epidemiologic studies and found that breast cancer mortality was strongly associated with sugar consumption with a correlation coefficient 0.9.
The review also found a positive association between breast cancer mortality and fat consumption, which is weaker than the association for sugar.
The possible link between breast cancer death and sugar consumption is insulin. Sugar consumption promotes the pancreas to produce insulin in large quantity, which also leads to the production of insulinlike growth hormone, a hormone that is known to promote the growth and progression of breast cancer.
High meat in the Western diet linked to increased risk of breast cancer in the West
Another study published in 1994 in Epidemiology shows that increased meat consumption was associated with increased risk of breast cancer. T o be exact, those in the upper quintile of meat consumption were 87% more likely to be diagnosed with breast cancer, compared with those in the lowest quintile of meat consumption.
The study also found a moderate association between total and saturated fat and the risk of breast cancer.
But other types of fat, protein, dairy products, poultry, or fish were not associated with breast cancer risk.
Paolo T oniolo and colleagues found these associations after they analyzed data from 14,291 New York City women who enrolled in the prospective cohort study of endogenous hormones, diet, and cancer between 1985 and 1991.
These studies suggest that high fat (particularly total and saturated fat, high sugar (simple sugars like cane sugar and high fructose corn syrup), and high meat (particularly red meat) in the Western diet can all contribute to the high risk of breast cancer in the West.
It should be noted that Western diet is not the only risk factor for breast cancer. An authorative organization has said that two most certain risk factors for breast cancer is hormone replacement therapy and radiation used in diagnostics and treatments.
