Channing Laboratory, Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, MA 02115, USA.
Br J Cancer. 2010 Feb 2;102(3):489-94. doi: 10.1038/sj.bjc.6605510. Epub 2010 Jan 5.
Choline and betaine, similar to folate, are nutrients involved in one-carbon metabolism and hypothesised to reduce breast cancer risk. No prospective study among post-menopausal women has examined choline and betaine intakes in relation to breast cancer risk.
We examined the intake of choline and betaine and breast cancer risk among 74 584 post-menopausal women in the Nurses' Health Study. Nutrient intake was assessed using a validated food-frequency questionnaire six times since 1984. During 20 years of follow-up from 1984 until 2004, we documented 3990 incident cases of invasive breast cancer.
Overall, choline (mean+/-s.d.; 326+/-61 mg per day) and betaine (104+/-33 mg per day) intake was not associated with a reduced risk of post-menopausal breast cancer. Participants in the highest quintile of intakes had multivariate relative risks of 1.10 (95% confidence interval (95% CI): 0.99-1.22; P-value, test for trend=0.14) for choline and 0.98 (95% CI: 0.89-1.09; P-value, test for trend=0.96) for betaine, compared with those in the lowest quintiles of intakes. The results were similar in breast cancer stratified by hormone receptor (oestrogen receptor/progesterone receptor) status. The association between choline intake and breast cancer risk did not differ appreciably by alcohol intake (non-drinker, <15 or 15+ g per day) or several other breast cancer risk factors, including family history of breast cancer, history of benign breast disease, body mass index, post-menopausal hormone use, and folate intake.
We found no evidence that higher intakes of choline and betaine reduce risk of breast cancer among post-menopausal women.
胆碱和甜菜碱与叶酸类似，是参与一碳代谢的营养素，据推测可降低乳腺癌风险。没有前瞻性研究在绝经后妇女中检查胆碱和甜菜碱的摄入量与乳腺癌风险的关系。
我们研究了 74584 名绝经后妇女的胆碱和甜菜碱摄入量与乳腺癌风险之间的关系。自 1984 年以来，通过验证后的食物频率问卷进行了 6 次营养素摄入评估。在 1984 年至 2004 年 20 年的随访期间，我们记录了 3990 例浸润性乳腺癌的发病情况。
总体而言，胆碱（平均值+/-标准差；326+/-61mg/天）和甜菜碱（104+/-33mg/天）的摄入量与绝经后乳腺癌的风险降低无关。摄入量最高五分位数的参与者的多变量相对风险为 1.10（95%置信区间（95%CI）：0.99-1.22；P 值，趋势检验=0.14）对于胆碱，与摄入量最低五分位数的参与者相比，0.98（95%CI：0.89-1.09；P 值，趋势检验=0.96）对于甜菜碱。在按激素受体（雌激素受体/孕激素受体）状态分层的乳腺癌中，结果相似。胆碱摄入量与乳腺癌风险之间的关联与饮酒量（非饮酒者、<15 或 15+g/天）或其他一些乳腺癌危险因素（包括乳腺癌家族史、良性乳腺疾病史、体重指数、绝经后激素使用和叶酸摄入量）无明显差异。
我们没有发现较高的胆碱和甜菜碱摄入量可降低绝经后妇女乳腺癌风险的证据。
