Dear Doctor: I'm 44, newly single, and have started lifting weights because I hear it can help with mood and confidence. Am I on the right track? Also, my brother insists I have to start eating a lot more protein if I want to see results in the mirror. Is this true?

Dear Reader: You're absolutely on the right track with adding exercise to your life. Numerous studies over the last few decades show a strong link between physical exertion and improved mental and emotional well-being. And while the so-called endorphin high of aerobic activities like running, cycling and gym-based exercise classes has gotten the most ink, there's a similar connection between resistance training (aka weight lifting) and improved mood.

In one study, healthy older adults who suffered from depression were placed on a two-month weight training program of three sessions per week. Among those who were assigned to the high-intensity group, which lifted heavier weights, testing showed that symptoms of depression were cut in half in more than 60 percent of participants. Among the low-intensity training group, close to 30 percent of participants saw similar results. What was really intriguing was that gains in muscle strength had a direct correlation to reduction in depression. The literature also shows a link between resistance training and a drop in levels of anxiety.

When it comes to the role of protein in building muscle by lifting weights, your brother is up on the latest developments. A recent review of existing research by scientists from several well-regarded institutions found that increasing protein intake beyond typical dietary needs resulted in a greater increase in muscle mass.

The scientists examined data from 49 studies with a total of 1,863 participants, both women and men. They focused on studies that lasted a minimum of six weeks and had a control group against which to compare results. They found that those weight lifters who boosted their protein intake not only increased muscle size and muscle mass more than the control group, but they also made measurable gains in the areas of strength and endurance. In fact, increased protein consumption resulted in an average 25 percent greater increase in muscle mass than the control groups, and a 10 percent gain in endurance. Also intriguing was the fact that this effect was particularly pronounced among participants who were older than 40.

So what's the magic protein number? According to the researchers' calculations, optimal protein consumption was 1.6 grams of protein per kilogram of body weight per day, or double the RDA of 0.8 gram of protein per kilogram of body weight. That means a 165-pound individual would need about 120 grams of protein per day. To put that into perspective, there are 6 grams of protein in an egg, about 40 in a chicken breast, and about 17 in a salmon fillet.

When it comes to all of this, both the exercise and the diet, we urge you (are any of our regular readers surprised?) to please check in with your family doctor before you get started.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I recently read that a modified Pap smear has the potential to show early warning signs of ovarian and endometrial cancers, as well as cervical cancer. How accurate is this test, and when might it be available?

Dear Reader: An almost all-purpose test is a tantalizing prospect. Already, the Pap smear and HPV testing are crucial screenings in the diagnosis of cervical cancer and have led to a significant decline in death rate from the disease. Yet thus far, screening tests for endometrial (uterine) cancer and ovarian cancer have not been promising. Endometrial cancer and ovarian cancer combined still claim the lives of about 25,000 women in the United States per year because such cancers are often found only after they have spread to other portions of the body. A screening test to find these cancers could dramatically reduce those numbers.

Such a test could be available in the relatively near future. A greater understanding of the gene mutations involved in these two cancers have spurred some scientists to propose a simple technique to find these mutations using DNA testing of the fluid obtained through the Pap smear. A study published in March assessed the technique's ability to detect such mutations in 382 women diagnosed with endometrial cancer, 245 women with ovarian cancer and 714 women without cancer.

Researchers looked for mutations within 18 genes and also for an abnormal number of chromosomes. The technique, called "PapSEEK," positively identified 81 percent of women with endometrial cancer, including 78 percent of those with early-stage endometrial cancer. However, it identified only 33 percent of women with ovarian cancer, including only 34 percent with early-stage disease.

In an attempt to improve these numbers, researchers took samples from farther within the uterus in a subset of patients. The test then positively identified 93 percent of women with endometrial cancer, and 45 percent of those with ovarian cancer.

The researchers also tested a subset of patients with ovarian cancer using PapSEEK and a blood test to detect circulating tumor-specific DNA. The positive rate then increased to 63 percent for ovarian cancer, including 54 percent with early-stage ovarian cancer. It's an improvement, but a lot of ovarian cancers would still be missed.

On the plus side, the rates of false positives were low with these tests. In the women without cancer, the rate of false positives was between zero and 1 percent.

Note that this was a retrospective study, meaning that the test was conducted among women who had already been diagnosed with cancer. It's unclear how well the test would work as a screening that could affect the course of the disease. A large screening study is needed to help us understand the true potential benefits of the test.

No doubt about it, however, the results are encouraging, especially as a way to detect endometrial cancer when used on samples taken from farther within the cervix and to detect ovarian cancer when used with a blood test.

Due to the need for more assessment, the test may not be available for several years, but it's good to know that our increased ability to conduct DNA testing is likely to help us, ultimately, catch these cancers early enough to save more lives.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Just how risky are sinus infections? I read about a teenager who died recently after a sinus infection spread to his brain. Is this common? How do you prevent a sinus infection?

Dear Reader: We hadn't heard about this before we received your letter, but we did a search and found the incident you're referring to.

A 13-year-old boy in Michigan who had been diagnosed with a sinus infection went on to develop migrainelike headaches. The severe headaches worsened over the course of several weeks and an MRI was performed. It was discovered that a viral infection had spread to his brain and caused blood clots, which led to a series of strokes, according to his family members. Despite emergency surgery, the boy passed away. It's a tragic story and, considering that sinus infections are common -- an estimated 31 million are diagnosed in the United States every year -- it's an alarming one. However, the fact is that these types of complications are rare.

The sinuses are pairs of air-filled cavities located behind the lower forehead, behind the nose, on either side of the bridge of the nose, and within the bony structures of the cheeks. In a heathy sinus, a thin layer of mucus catches dust, dirt or debris and, with the aid of tiny hairlike structures, clears it away. That mucus then drains into the nasal passage and winds up in the nasopharynx, which is where the very back of the nose and the throat converge. At that point, the mucus continues its journey down the esophagus and into the stomach.

A sinus infection occurs when a virus, bacterium or fungus causes the tissues that line these cavities to become inflamed. When this happens, the flow of mucus is blocked and it begins to collect in the sinus cavity. This can cause symptoms like congestion, postnasal drip, excess and sometimes discolored (usually greenish) mucus, tooth pain, a feeling of pressure, frontal headache, fatigue and even bad breath. In rare cases, the pathogens causing a sinus infection can cross the blood brain barrier, which is a filtering mechanism that protects brain tissues, and cause an abscess.

Conditions with similar symptoms, like colds or allergies, can be mistaken for a sinus infection. An accurate diagnosis requires an examination of the throat, nose and sinuses. This can include a physical examination with an endoscope, X-rays or a CT scan, and a mucus culture to pinpoint the cause of infection. Antibiotics may be used when the infection is bacterial but will not help with a viral infection. Symptoms can be eased with over-the-counter antihistamines, nasal decongestant sprays and nasal saline washes. Patients are often counseled to drink plenty of fluids to help thin the mucus.

Prevention consists of the same steps you take to avoid catching a cold or the flu. The Centers for Disease Control and Prevention suggest:

-- Practice good hand hygiene.

-- Keep the family up-to-date with immunizations.

-- Steer clear of individuals with upper respiratory infections.

-- Avoid exposure to tobacco smoke.

-- Use a humidifier -- and be sure to keep it clean.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)