There’s no actual way to measure the effectiveness of Tamoxifen while you’re taking it. However, researchers have identified a factor that strongly influences the effectiveness of Tamoxifen. It turns out that the effectiveness of Tamoxifen may be closely tied to your melatonin level.
Melatonin is a hormone and antioxidant naturally produced by your pineal gland (under your brain) when it gets dark in the evening. It induces sleepiness and kicks off your body’s “nightshift” processes, including hormone regeneration and repair of tissues from daily wear and tear. It has also, on its own, been demonstrated to have anticancer effects.1
To generate optimal amounts of melatonin, it’s important to sleep in a very dark room. Even small amounts of light in the room you sleep in can significantly reduce your melatonin production. (This may be one of the reasons that people who work night shifts have higher rates of cancer. 2,3) Melatonin production also declines with age.
New research, conducted on mice, revealed that mice who slept in the darkest conditions – and therefore had the highest levels of melatonin – experienced dramatic rates in tumor regression while on Tamoxifen. In mice whose melatonin levels were suppressed due to nighttime light exposure, tumors were barely affected by the presence of Tamoxifen.
These findings imply that to receive the full benefit of Tamoxifen, you need to be sleeping adequate hours in complete darkness.
Of course, adequate sound sleep is a critical element of any complete cancer prevention plan. This study simply provides another strong reason to create optimal conditions for deeply restful, healthful sleep.
If you’re on Tamoxifen, here’s what you can do now to increase your chances of deriving its full protective benefit:
- Get as much sleep as you can before midnight: take advantage of dark evening hours to get a jump on melatonin production.
- Consider sleeping with an eye mask: light hitting the retinas of your eyes turns off melatonin production. An eye mask is a good way to keep melatonin production flowing.
- Make your bedroom as dark as possible. Don’t sleep with the TV on. Cover or remove any digital light displays. Consider light-blocking window coverings.
Ironically, Tamoxifen produces hot flashes in many women, which in turn interfere with sleep. That’s another good reason to keep your bedroom very dark. Even if you’re not actually sleeping, you’ll continue to produce melatonin if you lie with your eyes closed in complete darkness. That may be a great time to practice deep, intentional breathing or a gratitude meditation, either of which may help you get back to sleep.
Your turn to comment below:
- Have you been able to sleep soundly since cancer treatment? If not, what’s keeping you from sleeping well?
- If you’re on Tamoxifen, how has it affected your sleep?
- What has helped you sleep well while on Tamoxifen?
1 AA Zamfir Chiru et al, Melatonin and cancer, J Med Life, Sep 15, 2014; 7(3): 373–374. PMCID: PMC4233441
2 He Cet al, Circadian disrupting exposures and breast cancer risk: a meta-analysis, Int Arch Occup Environ Health. 2014 Sep 27. PMID: 25261318
3 Jia Y et al, Does night work increase the risk of breast cancer? A systematic review and meta-analysis of epidemiological studies, Cancer Epidemiol. 2013 Jun; 37(3):197-206. PMID: 23403128
Keywords: Dr. Shani Fox, breast cancer, breast cancer prevention, cancer prevention plan, melatonin and cancer, Tamoxifen, Tamoxifen effectiveness
© 2014 Shani Fox, ND, LLC. All rights reserved.