Dear Doctor: I want to start feeding my baby solid food, but I read that rice cereal is contaminated with arsenic. What should I do?

Dear Reader: Your concern is understandable. The inorganic form of arsenic, found throughout nature in both the soil and water, is highly carcinogenic -- leading to an increased risk of bladder, skin and lung cancers. Areas with high levels of arsenic in the drinking water, such as Bangladesh, see higher rates of some cancers as a result.

In the United States, arsenic levels in drinking water are tightly regulated, which limits our overall risk from arsenic. That doesn't mean we're not exposed, however. Inorganic arsenic is still prevalent in our environment, and organic arsenic, which is much less toxic, can be found in most plants and animals in small amounts.

Rice poses a particular risk, as it concentrates inorganic arsenic more than other types of foods do. That's because rice is grown in stagnant water, which leads to conditions of low oxygen and allows arsenic to dissolve more easily into the water. The rice plant then more readily absorbs the arsenic. In fact, the level of uptake is 10 times that of wheat or barley.

The amount of arsenic in rice depends upon the type of rice and where it was grown. Rice grown in California appears to have less arsenic then rice grown in Texas and Louisiana. Sushi rice and basmati rice have lower amounts of arsenic, while organic brown rice concentrates more arsenic.

Rice cereals have traditionally been used to transition infants from milk to more solid foods because, for the most part, rice is hypoallergenic and a good alternative for children with allergies or intolerance to wheat-based cereals. But no one wants to worry that the foods meant to help children grow might actually be harming them.

So what should be done? Focus on the total risk.

To that end, the European Food Safety Authority has created the benchmark lower-dose limit, meaning the dose that would increase the risk of cancer by 1 percent. Consuming more than 2 servings of rice cereal per day would equal this dose. So, if you are transitioning your child to solid foods and they're consuming 3 or 4 servings of rice cereal per day, you should reassess your child's diet. This is especially true if you feed your child organic brown rice.

A big caveat is that the specific risk of cancer from rice consumption is not known. Researchers have not studied the connection between rice consumption in infants and cancer. Although a study of 200,000 people, published in the International Journal of Cancer, found no link between rice consumption and cancer, infants can concentrate more arsenic due to their smaller size.

My sense is that if you're transitioning your child to solid foods, rice cereal at 1 to 2 servings per day should be fine. What may be better is to balance rice cereals with other types of cereals, such as barley cereal or oatmeal cereal. Even better than cereals can be foods such as bananas, egg yolks and pureed vegetables.

It may get a little messy, so be prepared.

(Robert Ashley, M.D., is an internist and assistant professor of medicine at the University of California, Los Angeles.)

(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.)

Dear Doctor: My teenagers refuse to eat vegetables unless they're fried. Are they doomed to obesity and ill health?

Dear Reader: We wish we could reassure you and say it'll all be OK, but studies have long been clear on the matter. What your kids eat now will shape their health for years -- and maybe decades -- to come.

Poor eating habits have caused a spike in childhood obesity in the last few decades. Today, more than 17 percent of kids ages 2 to 17 qualify as obese. That's double what it was 20 years ago.

Being overweight has put young people at increased risk of all kinds of health problems and led to a sharp increase in the diagnosis of conditions such as diabetes, high blood pressure, elevated blood cholesterol, fatty liver, and even asthma and sleep disorders.

But before you confront your kids with a list of "don'ts," which teens are naturally primed to resist, be aware that the newest study on youth nutrition has some great news. It arms you with the information you need to right the nutritional course while encouraging your teens in a positive way.

Here's the gist: Young people who ate fruits, vegetables, lean proteins and whole grains, and who steered clear of sugar, red meat and processed foods, gained significantly less weight as they entered young adulthood.

The study, conducted by researchers at the University of Minnesota, followed the eating habits of 2,500 adolescents from the time they were 15 until they turned 25.

Researchers found that by eating well at age 15, young people developed the habit of good nutrition, and it carried on into their 20s and beyond.

The takeaway? You can guide your children to a more healthful adulthood by helping them establish good eating habits while they are in their teens.

Some strategies:

-- Stock the fridge with plenty of vegetables, fruits and whole-grain products.

-- Clear out the processed foods and the fatty, salty snacks.

-- Serve lean meats, poultry, fish, beans and legumes for protein.

-- Make sure that serving portions are a reasonable size.

-- Make the home a no-soda zone. This includes diet drinks.

-- Steer clear of sugar and sweets.

The goal is moderation, and your best chance at success is to get creative. Instead of being forbidden, let the fried foods your kids love become special-event treats. That way, they'll be less likely to feel deprived and sneak-eat. Cooking together -- scouting recipes, shopping, preparing the food and eating as a family -- can go a long way to cementing the new eating behavior.

Exercise makes a big difference, not just to teens but for adults as well. There's no better way than to lead by example. Start taking family hikes or bike rides. Pick out a local race to train for and set an in-family competition with personal goals and rewards.

If you market these changes as something that's fun for the kids and for yourself, you're far more likely to create healthy habits that will last for life.

(Eve Glazier, M.D., MBA, is an internist and assistant professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and primary care physician at UCLA Health.)

(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.)

Dear Doctor: Do I really need a yearly mammogram?

Dear Reader: This might be hard to accept, but if you're woman at low to average risk of breast cancer, you probably don't need a yearly mammogram. That's not to say we shouldn't give mammograms their due.

Mammograms can reduce deaths from breast cancer, and they're an important reason why breast cancer death rates have decreased over the last 40 years in this country. Studies have found a decreased death rate from breast cancer among women who have had mammograms compared to those who didn't.

Now let's look at just how much benefit. The public health advocacy group the U.S. Preventive Services Task Force calculated that, if 10,000 women between the ages of 39 and 49 had regular mammograms for 10 years, it would prevent three breast cancer deaths. For the same number of women between the ages of 50 and 59, there would be eight fewer breast cancer deaths. And for women between 60 and 69, there would be 21 fewer breast cancer deaths over that 10-year time period.

In short, the overall death rates were not significantly different between those women who had mammograms and those who didn't. This has especially been shown in studies in Canada and Sweden that compared the impact of annual mammograms with yearly breast exams from a health professional. In a 22-year Canadian study of 89,000 women, no difference in death rate was seen among women who had regular mammograms compared to those who had yearly breast exams with a health professional. This may point more to the importance of getting a yearly breast exam than the benefit of getting a mammogram.

Mammograms also have downsides. A primary one is that they have many false positives, leading to more imaging, breast biopsies and significant anxiety for patients. Another is that many breast cancers, such as ductal carcinoma in situ, would never be of clinical significance, so finding them on a mammogram is of little benefit.

That's not to say mammograms aren't useful. They do find breast cancers. But doctors and their patients need to discuss their risks and their benefits.

If you're a woman who has a mother or a sister with breast cancer, or if you have the BRCA1 or BRCA2 gene mutation that increases breast cancer risk, then a yearly mammogram after the age of 40 is a good idea. If you have a combination of risk factors -- such as having had your first baby after the age of 30, having later-onset menopause or having had an earlier onset of menstruation -- then a mammogram is likely a good idea.

However, if you're at average risk of breast cancer and between the ages of 40 and 49, there is only a small statistical benefit in having a mammogram, which should be balanced with the risks of testing.

If you are between the ages of 50 and 69, the benefit of a mammogram may overcome risk. At that age, you should get a mammogram every two years.

If you're older than 70, keep in mind that breast cancer rates increase up to the age of 80, so the screening could have a benefit. But that benefit must be weighed against the likelihood of dying from something else. Here again, the recommendation is for a mammogram every two years, but you should discuss your individual needs with your doctor.

Breast cancer screening is still evolving, with newer 3-D types of mammograms, breast MRIs and the possibility of biochemical markers to detect breast cancer. We'll need future studies of these technologies to assess their effectiveness at detecting breast cancer and reducing death rates. In time, the recommendations may change yet again.

(Robert Ashley, M.D., is an internist and assistant professor of medicine at the University of California, Los Angeles.)

(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.)