Archive 2007 2008 2009 2010

Q: I bought some ground beef that was red on the outside but gray inside. What causes this, and is the meat safe?

A: It should be fine. Meat contains a pigment called myoglobin that turns bright red when exposed to oxygen. Grocery stores typically cover ground beef with a plastic wrap that allows some oxygen to penetrate, so that the surface of the meat turns this appealing red color, which consumers have come to associate with freshness. When ground beef is not exposed to oxygen (as in the inside of the packaged meat), the myoglobin turns grayish-brown after a few days. It may look less appetizing but is safe.

If the ground meat is gray or brown throughout, however, that could indicate that it’s beginning to spoil. If you just bought it, you may want to return it. "Spoilage bacteria," though generally harmless, can make meat smell and cause other signs of deterioration. If you still want to eat it, it’s important to cook it thoroughly.

Of more concern, ground beef is susceptible to contamination from Salmonella, E. coli, and other bacteria that do not affect the color or smell of meat but can make you sick—so it’s essential that you handle and cook all ground beef properly. Use or freeze it within a day or two of purchase, and cook it to 160°F. (71°C.); always use a meat thermometer to check. Color is an unreliable indicator of doneness, as the meat can turn brown before it reaches a temperature that kills all bacteria; conversely, some ground beef may remain pink after it’s cooked to a safe temperature.

By the way, meat can also turn gray in the freezer. It’s perfectly fine and safe to eat.

Q: I lost 50 pounds and now have flabby skin folds. Is there anything I can do about this problem? What about collagen supplements?

A: The skin is fairly elastic—it stretches and contracts as we move our joints and in other circumstances, such as pregnancy and childbirth. Skin contains collagen and elastin, two proteins that share some properties with a rubber band. Like a rubber band, they lose their ability to contract if stretched too much for too long a time.
The "anatomy" of skin (that is, thickness and other qualities, including elasticity) varies all over the body; elasticity depends on your age (young skin is more elastic) and the amount of weight you lose. Sun exposure and smoking reduce elasticity.

No food or supplement, including collagen supplements, will correct sagging skin. Exercise won’t remove or alter flabby skin, but strength training can tone and bulk up muscles under the skin, and that can improve appearance a little. You would have to build lots of muscle to fill out the sagging skin.

If your problem is severe, your physician may refer you to a plastic surgeon. People undergoing weight-loss surgery, who may lose half their body weight, often have surgery to remove excess skin. There are many surgical procedures: abdominoplasty (tummy tuck), gluteoplasty (for the buttocks), and brachioplasty (arm lifts). Surgery is expensive, and insurance usually does not cover it, or only part of it. It will produce scarring, and carries risks. You must be committed not to regain the weight. There are also some nonsurgical, noninvasive techniques that use lasers to tighten the skin, but these are of limited usefulness.

Q: Can the supplement Lipo-Flavonoid help tinnitus, as claimed?

A: It’s certainly not the miracle cure its website makes it out to be. Tinnitus (see Wellness Letter, July 2009) is characterized by phantom noise no one else hears—such as ringing, clanging, and whistling. It can be caused by many conditions. Because conventional treatments are not always effective, people with tinnitus often turn to alternative remedies, such as certain B vitamins, vitamin C, and bioflavonoids—the basic ingredients of the supplement Lipo-Flavonoid. Created in 1961, Lipo-Flavonoid is said to improve tinnitus, as well as Ménière’s disease, an inner ear disorder whose symptoms include episodes of tinnitus.

One biological property of flavonoids is that they inhibit histamine release from cells, according to a 2008 paper in Clinics in Dermatology. And lowering histamine levels in the body may help manage Ménière’s disease, in part by improving microcirculation in the inner ear. But that doesn’t mean the bioflavonoids in Lipo-Flavonoid would have this benefit.

It’s also claimed that bioflavonoids and other antioxidants help tinnitus by protecting blood vessels from cell-damaging free radicals and by improving microcirculation. It’s not clear, though, whether free radicals even play a role in the condition.

As for B vitamins, some older research suggests there may be a link between tinnitus and vitamin B12 deficiency, and that various B supplements, including B12, may improve symptoms. But a review of studies in the Journal of Layrngology and Otology in 2007 concluded that there’s no convincing evidence that B vitamins help tinnitus not caused by a deficiency.

Bottom line: Most of the research cited by the company is decades old, and the only study that seems to have tested the actual supplement, from 1970, is not available for review. It is probably safe to try Lipo-Flavonoid, but we’ve seen no evidence that would make us recommend it.

Q: What’s the difference between an ophthalmologist and optometrist? Is one preferable?

A: An ophthalmologist is an M.D. who specializes in eye care and has three or more years of residency training beyond medical school. An optometrist is an O.D., or doctor of optometry, with four years of graduate training at a college of optometry.

Both diagnose vision problems such as near- and farsightedness, prescribe lenses, and screen for glaucoma, cataracts, and macular degeneration. Both can prescribe medicines for eye diseases. Ophthalmologists have traditionally treated glaucoma, but over the past decade optometrists have gained the right to treat it as well. Only ophthalmologists can perform surgery. In general, for the treatment of more serious eye disorders, you may need to go to an ophthalmologist.

In addition, there are opticians, who are not doctors and are solely licensed to make, fit, and sell corrective lenses as prescribed by an optometrist or ophthalmologist.

UC Berkeley Wellness Letter, June 2010