Recent Blog Articles
Cutting and self-harm: Why it happens and what to do
Discrimination at work is linked to high blood pressure
Pouring from an empty cup? Three ways to refill emotionally
Give praise to the elbow: A bending, twisting marvel
Sneezy and dopey? Seasonal allergies and your brain
The FDA relaxes restrictions on blood donation
Apps to accelerometers: Can technology improve mental health in older adults?
Swimming and skin: What to know if a child has eczema
A muscle-building obsession in boys: What to know and do
Natural disasters strike everywhere: Ways to help protect your health
B vitamins may raise risk of lung cancer in men who smoke
In the journals
Smoking causes lung cancer — no surprise there. But a new study found that high dosages of vitamin B6 or B12 supplements were associated with three to four times the lung cancer risk in male smokers compared with smokers who did not take the supplements. The results were published in the Aug. 22, 2017, Journal of Clinical Oncology.
Researchers examined information from more than 44,000 men ages 50 to 76. At enrollment, the men reported on their smoking history and their B vitamin supplement use over the previous 10 years. In the study, high intake of B vitamin was classified as 20 milligrams (mg) of B6 per day or 55 micrograms (mcg) of B12. (The recommended daily intakes for men ages 51 and older are 1.7 mg for B6 and 2.4 mcg for B12.)
B vitamins help strengthen the immune system, according to the researchers, so it is not clear why high levels of supplemental B vitamins would increase rather than decrease smokers' lung cancer risk. They speculated that the B vitamins might feed small, undetected tumors and make them grow faster.
B vitamins aside, not smoking remains the most important way to prevent lung cancer. In fact, the researchers also found that men who quit smoking for at least 10 years before the study and also took high dosages of the B vitamins did not have a higher risk of lung cancer. In fact, their risk was equal to that of men who had never smoked.
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
Free Healthbeat Signup
Get the latest in health news delivered to your inbox!