Question: My son’s four-year-old friend appears to be obese already. What can I do with my own four-year-old—who right now is of average height and weight—to ensure he doesn’t become overweight?

Answer: A child is not going to become obese if he goes to one birthday party at McDonald’s. But if your family goes out to fast food three or four times a week, and the house is stocked with junk food, then you put the child at risk. As the parent, it’s your job to ensure that the food that’s available to him is good, healthy, high-quality food. Plenty of fruits and vegetables, organic if possible.

Four-year-olds should never do the choosing at the grocery store. Things like chips and cookies are appealing, but if you don’t want your kids eating that stuff on a regular basis, keep it out of the house. It’s also your job to model good eating habits and good exercise habits for your child. Get out and play. Be active. Show him you run and eat broccoli, and he’ll learn from you. —Dr. Barbara L. Gablehouse, Pediatrics; Children’s Hospital, Lutheran Medical Center

Q: Once and for all: Do childhood vaccines cause autism?

A: In February a special federal court ruled that vaccines—specifically the measles-mumps-rubella vaccine and vaccines that contained mercury—did not cause autism in three children. The nature of science is to ask a question and then to try to seek evidence. Pediatricians have been interested in the question of a potential link between vaccines and autism, and this hypothesis has been tested numerous times. No one knows what causes autism, but the scientific evidence to date is quite clear that vaccines do not cause the disease. —Dr. John Ogle, Pediatric Infectious Disease; Children’s Hospital, Denver Health Medical Center

Q: When I run in Denver, I feel completely dehydrated. Is it the altitude?

A: Being at altitude, being closer to the sun, certainly means you need to take a lot of things into consideration to protect yourself from conditions like dehydration. Insensible heat loss (losing moisture from your skin and lungs simply by evaporation) can contribute to dehydration if you exercise routinely. This condition needs to be taken seriously in our climate, especially because we don’t have a humid atmosphere layer in Denver that keeps our moisture levels intact.

A really easy way to tell if you’re dehydrated is to look at the color of your urine. If it’s dark yellow, you’re dehydrated. A good rule of thumb is to keep the color of your urine light yellow to clear. Thirst is not a good indicator. By the time you are thirsty, you’re already dehydrated.

Some people get excessive in their intake of fluid because they’re afraid of getting dehydrated, and they drink too much water. That dilutes the sodium in your body. It’s called hyponatremia, or water intoxication (a disturbance in electrolytes or salts in the blood), and that’s not good. It can lead to neurological issues, which is a worst-case scenario, but it does happen to marathon runners. Use your urine color as your guide, and don’t overdo it. Everything has to be in balance. —Dr. Deborah Saint-Phard, Sports Medicine; Boulder Community Hospital, University of Colorado Hospital

Q: Seems like everyone has a food allergy these days. What’s the deal?

A: Allergic diseases as a whole, including food allergies, are on the rise. Although we aren’t sure why, there are several hypotheses. The hygiene hypothesis proposes that our immune systems need the right interactions with bacteria to develop appropriately. Because we now live in such a clean environment, these interactions don’t occur, resulting in increased allergies. Another idea suggests decreased levels of vitamin D, which helps regulate the immune system, are partially to blame.

A true allergy is when the immune system is involved in causing a reaction. (For example, lactose intolerance is an example of a metabolic deficiency and has nothing to do with the immune system.) So when someone says, “Oh, I’m allergic to X because that food makes my stomach hurt,” it’s often misleading because it may be an intolerance rather than an allergy. The most important thing to remember is that if someone is having unexplained symptoms—problems with respiration or the gastrointestinal tract—that aren’t going away, it’s time to talk to a doctor. —Dr. Dan Atkins, Allergy and Immunology; Children’s Hospital, National Jewish Health, University of Colorado Hospital

Q: As American women are trying to have children later in life, what are the risks for mom and baby? Is there an age at which their fertility starts to change?

A: There are additional risks for mother and child when starting a family later. Women’s fertility declines beginning at age 30, the rate of decline increases at 35, by 40 it drops even more abruptly, and it’s virtually absent by about 45 in the majority of women. Still, women have been delaying childbearing significantly over the past 30 years. In Scandinavian countries, the average age of women at the birth of their first child has gone from 24 to 34 just in the past 30 years. The trend seems even more extreme in the United States, with many women waiting until their late 30s or early 40s to begin a family.

Besides declining fertility, older women have increased risks for pregnancy complications such as high blood pressure, gestational diabetes, fetal growth restriction, and the need for a Cesarean delivery. Additionally, there is an increased risk for chromosomal abnormalities in the baby as women’s eggs age. While an amniocentesis can check for these, there is an increased risk for unfavorable results in older moms, along with a higher rate of miscarriage.—Dr. William B. Schoolcraft, Reproductive Endocrinology/Infertility; Avista Adventist Hospital, Rose Medical Center, Sky Ridge Medical Center, Swedish Medical Center

Q: A bunch of foods are promoting health benefits beyond simple nutrition, like those yogurts that help digestion. Is this just marketing? Or do these things actually work?

A: These products are probably not harmful, and there is research that shows probiotics—the beneficial bacteria or yeasts being used in some yogurts—can help people with diarrhea, immune problems, even skin disorders. When people hear the word “bacteria,” they naturally think of something that is bad or harmful, but bacteria can be beneficial, as there is an ongoing battle in the body to balance bacteria. The concept of eating products like yogurt with added probiotics—yogurt naturally has bacteria—is that you will have more of the good bacteria to fight the bad.

But whether products with added probiotics could help people who are already healthy is unknown. How healthy is more healthy? And although the FDA does regulate these biological therapy products, they fall in a gray zone between chemicals such as drugs, which are also regulated, and supplements like vitamins, which are not. In general, these foods appear to be safe; I don’t think people are going to hurt themselves by eating yogurt. At worst, though, these products may be ineffective, and you should talk to your doctor to make sure that the extra money you are spending on these products really benefits you. —Dr. Daniel Bessesen, Endocrinology, Diabetes, and Metabolism; Denver Health Medical Center, University of Colorado Hospital

Q: I’m a 35-year-old male, and my father is a prostate and colon cancer survivor. When should I start having screenings for these diseases?

A: There’s a lot more known about colon cancer and heredity than there is with prostate cancer, though both can be due to an inherited predisposition. People who have a first-degree relative with colon cancer have an increased risk. The standard screening test for colon cancer is the colonoscopy, which is typically done at age 50. However, because you have a family history, I would recommend having the procedure done 10 years before the age that your father was diagnosed. Some families have a hereditary predisposition to colon cancer, such as Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer), which raises the risk for colon cancer much higher than it would from just having a first-degree relative who’d had the disease. To be considered for genetic testing for hereditary causes of colon cancer, you or your father would meet with a genetic counselor, and your family history would be further analyzed to see if testing would be warranted.

As for prostate cancer, again, men routinely have the prostate-specific antigen, or PSA, blood test at age 50, but for those who have a strong family history of the disease, you’d want to have the test done at age 40. Prostate cancer is a slow-growing cancer, but if you’re diagnosed with it when you’re young, you’ll have to discuss with your physician how best to treat the cancer. In older men that develop prostate cancer, the likelihood is that they’ll die with prostate cancer rather than die from it. —Dr. Allen Cohn, Medical Oncology; Presbyterian/St. Luke’s Medical Center, St. Joseph Hospital

Q: My doctor suggested I have “microfracture” surgery to repair the cartilage in my left knee. I hear about all these NBA guys getting the surgery, with mixed results. Would I still be able to ski if I decide to have the procedure?

A: Skiing after microfracture surgery? That’s a definite maybe. Unfortunately, our solutions for injuries of articular cartilage—think of that white, glistening stuff on the surface of the end of a chicken bone—are far from perfect. While articular cartilage is an ideal joint-bearing surface in terms of its low friction (it’s 10 times slicker than an ice skate on ice) and numbness (cartilage has no nerves), it has limited, if any, ability to heal or regenerate. In the microfracture procedure, the surgeon uses a small ice-pick-like tool to make a series of tiny puncture holes (fractures) in the exposed surface of bone. These puncture marks bleed, and, if the procedure is successful, that bleeding coagulates and hardens into a layer of scar tissue that covers and protects the area of injury.

While this all looks great on paper, in real life the scar-tissue “patch” that we try to achieve with microfracture isn’t as numb, slick, or durable as the original articular cartilage, and patient satisfaction with the procedure is only about 70 percent. A much better solution would be to invent a pill, shot, or surgical procedure that would stimulate the body into resurfacing the defect with the original material. While I don’t have that solution to offer my patients today, some of our country’s top bioengineers (including the University of Colorado’s Dr. Kristi Anseth) are working to get us there. —Dr. Ted Parks, Orthopedic Surgery; Presbyterian/St. Luke’s Medical Center, St. Joseph Hospital

Q: I’m pretty stressed out between work, the economy, and paying my mortgage. What can I do to ease my stress levels?

A: A good technique is to list major stresses and prioritize those that can be most easily dealt with. In so doing, you gain a sense of accomplishment and mastery. For those stressed by a large mortgage, now is a time to look at the feasibility of refinancing and possibly consolidating debt to be more manageable. If your career seems to be getting you down, now may be the time to reconsider increasing your education and looking at careers that are showing growth potential. Take a look at what is positive about your current job, and assess if there are ways to enhance these aspects. Now is a time to focus on the present rather than the distant future. Volunteer your time. Give to others: It provides a sense of well-being and a sense of altruism as you focus on something for others rather than your own concerns. Reorganize your own environment, and donate what you no longer need. Most important: Take time to “feed the soul,” and be thankful for what you have. —Dr. Robert House Jr., Psychiatry; Denver Health Medical Center, University of Colorado Hospital

Q: I have chronic lower back pain and have had a couple of specific disc injuries (one bulging, one herniated). How do I weigh the cost-benefit of having surgery versus rehab?

A: At least 85 percent of the population will experience some type of back pain in their lifetimes. But even if you’ve had a couple of injuries and chronic pain, it would potentially be of great benefit to try a course of physical therapy. Unless you are having weakness and/or some other nerve-type issue from the bulging and herniated discs, I would not recommend pursuing surgery as the first line of treatment. Many people have back and disc injuries, including herniations, that can be treated successfully with nonoperative management.

If you have tried physical therapy and continue to have problems, then it might be time to consider surgical options. However, despite the potential benefits surgery has, there still are risks, including injury to the nerves, infection, and lingering pain from surgery. Before deciding to have surgery, it would be wise to see if there are other alternatives, such as an epidural injection to reduce the inflammation around the discs and the nerves. Also, getting a second opinion from a fellowship-trained back surgeon would be appropriate. —Dr. Eric McCarty, Sports Medicine; Boulder Community Hospital, University of Colorado Hospital

Q: Medical spas are everywhere now. How safe are they?

A: Medical spas aren’t well-regulated, and although some are run by dermatologists and plastic surgeons, others may be operated by people with varying amounts of training and supervision. The industry is lucrative, and spas may be owned by businesspeople—not doctors—who hire an M.D. to supervise. Someone who’s in business to make money may not have the patient’s best interest in mind. So if you’re thinking about visiting a medical spa, you’ll want to beware. Investigate the technicians’ training and background: Is there a certified dermatologist or plastic surgeon on site? Patients should also have a clear understanding of what the treatment can do, how long it will last, and of possible complications. Most people don’t get hurt at these spas, but their expectations sometimes aren’t met and treatments are expensive. —Dr. Barbara R. Reed, Dermatology; Presbyterian/St. Luke’s Medical Center, Rose Medical Center

Q: Is there a cure for women with low libido?

A: There is no magic pill for women with low desire. There are so many components—even relatively mundane things like day-to-day stress and a woman’s perception of her relationship with her partner may be part of the issue. There has been some preliminary research on the benefit of testosterone patches on the libido of postmenopausal women, but the FDA wants more safety data before recommending this treatment. Some doctors do prescribe off-label testosterone to women, but I do not. If your doctor does prescribe testosterone, you would need very close monitoring—the side effects of too high a dose can range from acne to a deepening of the voice. If you’re experiencing a lack of desire, you’ll want to decrease your stress, ensure that you’re getting enough sleep, and set aside time in your schedule to be intimate with your partner. The next step might be to seek a psychologist who specializes in issues of sexuality. —Dr. Kelly Moore, Obstetrics and Gynecology; Rose Medical Center

Q: I keep hearing about sepsis on the news. How do I know if that cut I got hiking is infected, and how would I know if I’m septic?

A: Infected wounds that cause sepsis are hot, red, and angry-looking. The biggest thing is to recognize if the pain is out of proportion to the size of the wound. Is there spreading or streaking redness? Is the wound warm to the touch? Is there a discharge with puss? These infections can just take off: Within a matter of hours this bacteria and released toxin can destroy large areas of tissue. The antibiotics that we historically used to treat infections like this are not as effective anymore. Over the past five years there has been a growing incidence of MRSA infections—often called staph infections—that are immune to common antibiotics and can be fatal. We used to think these types of infections were hospital-acquired, but we now know you can get them anywhere. As a result, we have to be more prudent with antibiotics and use them in the right situations. The majority of times, if caught early, these infections can be treated before they lead to sepsis. So be aware. Mark the border of an angry wound so that you can easily see if the redness and swelling are expanding rapidly over time. If the wound is not getting better, seek help immediately. —Dr. David Mellman, Internal Medicine; Rose Medical Center

Q: I’ve heard rumors that last year’s flu vaccine didn’t work. What’s your take on the efficacy of flu vaccinations?

A: As a general rule, they’re fairly effective—I’d say 75 to 80 percent effective. In the United States we have about 36,000 deaths a year from the flu, so it’s important to get vaccinated. There’s an initiative in place that by 2010 the federal government wants 90 percent of Americans to be vaccinated, but we’re way off.

I have no objections to giving the flu vaccine to everyone, but it’s most important for those 60 and above, for people with compromised immunity, like those with HIV, and for kids. I generally use the injected vaccine, which has a deactivated form of the virus. The other kind is the nasal spray vaccine, which has an active, live version. With the deactivated version, the body takes it in and uses it as a stimulus to prevent the reoccurrence of influenza. You can still get the flu, even if you have had the vaccine—but it’ll help decrease the symptoms you’ll experience. —Dr. Kenneth S. Greenberg, Infectious Disease; Rose Medical Center

Q: I hear my Boulder friends talking about dietary “cleanses” all the time. Do they have any health benefits?

A: Colon cleansing is promoted for improving overall health, reducing weight and fatigue, toxin removal, and to alleviate constipation and bloating. Of course, the colon and liver naturally remove toxins from the body, but people often try to “help” their systems along using these cleanses. The best way to deal with reducing toxins in the intestines is to reduce intake by eating organic food, increase fiber and water intake to flush your system, exercise to promote intestinal motility, and use natural, antioxidant-rich foods. Reducing processed foods and foods that may contain chemicals or preservatives may also be beneficial. There is some evidence that toxins irritate the lining of the intestines and colon, and that reducing those irritants can help avoid disease in the long term.

If you change your diet and still experience intestinal symptoms such as bloating or constipation, and feel heavy or fatigued, then speak with your doctor. These symptoms could be a sign of a more serious health concern such as thyroid disease, gluten or other food allergy, or colon cancer. —Dr. Jonathan D. Zonca, Family Medicine; Rose Medical Center