Archive 2005 2006 2007 2008

Q: Should I have the genetic test for breast cancer if I have no family history of the disease?

A: No. The U.S. Preventive Services Task Force recently recommended against routine genetic screening and advised that only women with a specific family history should consider having the blood test. Only about 2% of women have family history patterns that would warrant testing.

All women carry the BRCA1 and BRCA2 genes, which are involved in normal cell growth. Though BRCA stands for BReast CAncer, only women who inherit mutations in these genes are at higher risk of developing breast (and ovarian) cancer. It’s estimated that only 1 in 300 to 500 women in the U.S. carries the actual BRCA mutations. Moreover, just 5 to 10% of breast cancers are caused by these mutations.

Certain BRCA mutations are more common in women of Ashkenazi Jewish heritage. They might consider testing if they have a first-degree relative (mother or sister) or two second-degree relatives (aunt or grandmother) on the same side of the family who have had breast or ovarian cancer. Other women at increased risk are those with: multiple family members who have had either cancer; a relative who tested positive for the gene mutations; or a male relative who had breast cancer.

If you have questions about your personal risk, talk to your physician or a genetics counselor. For more information, go to www.guideline.gov (search for "breast cancer gene testing"). Testing costs range from several hundred to several thousand dollars, and insurance policies vary in their coverage. If you get tested, you may want to find out about privacy protection laws in your state before submitting charges.

Q. Is it safe to eat the outer edges of lettuce leaves that have turned brown?

A: Yes. It’s not a health issue and does not indicate a loss of nutrients. Still, most people find brown lettuce unappealing and will want to cut off the discolored parts.

Browning usually results from oxidation caused by exposure to air when the leaves have been bruised or cut. Another cause is "tipburn," which occurs in the field because of climate or soil conditions. Exposure to the ripening chemical ethylene (produced naturally by most fruits, but also used commercially as a ripening agent) can produce browning as well.

Bacteria and fungi can also cause browning, but these are not a health hazard, according to Dr. Tim Hartz, a crop specialist at the University of California, Davis. Lettuce and other produce can harbor harmful bacteria, of course, but these do not cause browning.

Select lettuce that looks fresh (not wilted), since it will taste better and last longer. To reduce browning at home, keep lettuce in the coolest part of the refrigerator, away from high-ethylene-producing fruits (such as apples, pears, peaches, bananas, tomatoes, and cantaloupe), and keep it dry.

Q: I grind my teeth at night. Is it okay to use an off-the-shelf mouth guard?

A: Though they are cheaper than customized mouth guards made by a dentist, which can cost several hundred dollars, over-the-counter products don’t work well for most people with bruxism (teeth grinding), says Dr. Edward Grace, director of the Brotman Facial Pain Center at the University of Maryland Dental School. Moreover, if they don’t fit right, they could cause other problems.

But you certainly can try one to see if it helps. Check with your dentist first if you have gum disease, loose or missing teeth, mouth ulcers, or other dental problems. There are many different night guards available. Look for one marketed specifically for bruxism, not a sports mouth guard. "Boil and bite" models (such as the Doctor’s NightGuard available at drugstores, or the BruxGuard available only from dentists) may give a better fit than pre-formed devices.

Mouth guards—even custom-fitted ones—are not, however, a cure for bruxism, because they don’t address the cause of the problem, which may be a misaligned bite or sleep apnea, for instance. Stress and anger may also be involved. Relaxation techniques, behavior therapy, and/or biofeedback may help break the habit.

Q: I get headaches when I fly. Could it have something to do with the cabin pressure?

A: It’s possible. Because the amount of oxygen our bodies can absorb from the atmosphere at cruising altitude (generally 30,000 feet or above) is too low to survive on, commercial airplane cabins are pressurized. But what you may not realize is that the pressure is typically equivalent to an altitude of 5,000 to 8,000 feet, making for somewhat thin air on board.

The effect of reduced oxygen pressure varies from person to person. Some people may experience a drop in their blood oxygen, a condition called hypoxia, which can bring on headaches and other symptoms. Most healthy people can compensate, but if you’re older, you may have more difficulty. People with heart or respiratory problems should check with their doctors before flying. Alcohol, smoking, and some medications (including antihistamines) can exacerbate hypoxia.

By the way, there are other reasons why you might get headaches while flying, including the stress and fatigue that often accompany travel.

UC Berkeley Wellness Letter, May 2006