Get enough sleep, people!

Responding to Wendy Chen's comment on our first blog, I went on to read the article.  In the Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study article that Wendy referred to us, it said that among Japanese women, "those who slept 6h or less having a significantly increased risk."

According to answers.com, "Natural melatonin production decreases with age and the decrease is associated with some sleep disorders."  And the Ohsaki Cohort Study said that with a lower melatonin level in our body, there is an increased risk of breast cancer.  Melatonin tends to inhibit cell growth on breast cancer cell lines.

The study stated its limitation, which is that "we had no information on such factors as sleep quality, the timing of sleep, the use of sleep medication, or the presence of sleeping disorders that can influence sleep duration and thereby might affect breast cancer risk."

I can only say that let's not underestimate the importance of longer sleeping time.  Shorter sleep duration not only can increase risk of breast cancer, but also can weaken our immune system and decrease our work productivity the following day. 

I'll repeat myself again: Get enough sleep, people!