Sweet, traditional Chinese dietary patterns protect against breast cancer risk
Sweet and traditional Chinese dietary patterns appear to significantly reduce the risk of breast cancer in both pre- and postmenopausal Chinese women, a new population-based study has shown.
“[W]e identified four major dietary patterns which were labeled as salty, vegetarian, sweet and traditional Chinese,” said the researchers.
“The traditional Chinese pattern and the sweet pattern were found to be significantly associated with a reduced risk of breast cancer, and such associations were not influenced by menopausal status, weight status or reproductive history,” they added.
Investigators administered food frequency questionnaires to 818 primary breast cancer patients (mean age 54.8±11.1 years) and 935 age-matched controls (mean age 54.3±11.13 years; p=0.337). The association of the four dietary patterns (salty, vegetarian, sweet and traditional Chinese) with breast cancer risk was evaluated using multivariate logistic regression analyses.
The highest quartile of the sweet dietary pattern had significantly reduced risks of breast cancer in both pre- (odds ratio [OR], 0.47; 95 percent CI, 0.28 to 0.79; p=0.017 for trend) and post- (OR, 0.68; 0.47 to 0.98; p=0.03 for trend) menopausal women compared with the first quartile. [PLoS One 2017;doi:10.1371/journal.pone.0184453]
The same trend was observed for the traditional Chinese dietary pattern. In postmenopausal women, the risk of breast cancer was lower in the second (OR, 0.64; 0.45 to 0.90), third (OR, 0.45; 0.32 to 0.63) and fourth (OR, 0.68; 0.48 to 0.97; p=0.006 for trend) quartiles compared to those in the first quartile.
Similarly, in premenopausal women, the risk of breast cancer was lower in the second (OR, 0.53; 0.33 to 0.85), third (OR, 0.53; 0.32 to 0.86) and fourth (OR, 0.47; 0.29 to 0.76; p=0.004 for trend) quartiles of the traditional Chinese dietary pattern compared with the first quartile.
Interestingly, there were no significant associations between the salty and vegetarian dietary patterns and risk of breast cancer.
While it has been largely accepted that vegetables exert a protective effect against cancers, “there is still no consistency achieved in the relationship between dietary patterns, in which more vegetables or fruit intake is involved, and breast cancer,” said researchers.
In a study by Sant et al, it appeared that only raw vegetables could appreciably reduce the risk of only specific types of breast cancer. In the current study, however, Chinese diets tend to include cooked vegetables, which may explain this discrepancy. [Int J Cancer 2007;121:911-914]
The salty dietary pattern was rich in foods that had high salt content, such as soy sauce and monosodium glutamate, while the vegetarian pattern had diets that were high in vegetables and fruits and low in meat and fried food.
The sweet pattern was defined as diets rich in sweetened beverages and sugary foods, and the traditional Chinese pattern mainly included eggs, whole cereal, vegetables, fruits and meat.
Almost a third (32.9 percent) of the variance in food intake of the study sample was explained by the four dietary patterns. Specifically, the salty dietary patterns explained 11.72 percent; the vegetarian, 11.32 percent; the sweet, 7.53 percent and the traditional Chinese, 5.76 percent.
“To conclude, the traditional Chinese dietary pattern (characterized by a relatively balanced intake of various nutrients) and a sweet pattern may protect against breast cancer among women in China, whereas a vegetarian pattern and a salty pattern appear not to be associated in this population,” said researchers.