● DEAR MAYO CLINIC: Does stress cause irritable bowel syndrome or other gastrointestinal problems? — Tucson

Stress doesn't cause irritable bowel syndrome or other gastrointestinal problems, but it can make the symptoms worse.

The gastrointestinal tract is governed by the autonomic nervous system, the nerve network that serves internal organs and works mostly without our thinking about it. The autonomic system has two parts: the sympathetic nervous system, which activates in stressful situations; and the parasympathetic nervous system, the counterpart that promotes quiet activities (such as digesting your dinner).

When stress occurs — work problems, disagreements, money woes or true danger — the sympathetic nervous system goes into high gear. Your body responds in fight-or-flight mode, prepared to face or run away from danger, even if the "danger" is a traffic ticket or a teenager driving you crazy.

When the sympathetic system is in charge, in essence, your gastrointestinal system turns off. The body is not worried about digestion when it's geared up to respond to an emergency.

That is the motor side of things; yet the gastrointestinal system also has a sensory side. The autonomic nervous system sends sensory signals to the brain. During times of stress, our brains are looking for clues from all over; our bodies are more vigilant about sensing what is going on. Under stress, the gut feels more and does less. For anyone, stomachaches and diarrhea are common symptoms of stress.

So, it's no surprise that stress can intensify symptoms of gastrointestinal conditions.

With irritable bowel syndrome, a chronic condition with symptoms that include abdominal pain, cramping, gas, diarrhea and constipation, the severity of symptoms varies widely. Managing stress helps minimize symptoms.

For many people, managing stress is the first line of treatment, along with changes in lifestyle and diet. Medication can be helpful for people with more severe symptoms.

READERS: Heart disease is the No. 1 killer of women. Yet many women underestimate their risk of heart disease because they are unaware of the risk factors.

Mayo Clinic Women's HealthSource recommends that women be tested for certain risks and track the results. Tests include:

● Lipoprotein (lipid) profile. This blood test is recommended once every five years to measure your cholesterol levels. Optimal low-density lipoprotein — the "bad" cholesterol — is 100 milligrams per deciliter or lower. Optimal high-density lipoprotein — the "good" cholesterol — is between 50 and 59 mg/dL.

● Blood pressure: A measurement is recommended every two years — or more often if you have blood pressure greater than 135/85 millimeters of mercury (mm Hg). A blood pressure of less than 120/80 mm Hg is optimal.

● Fasting plasma glucose. This blood test checks for diabetes and is recommended every three years, beginning at age 45. An optimal reading is less than 100 mg/dL.

● Body-mass index: BMI is a measure of weight in relation to height. Optimal BMI is 19 to 24, and measurement is recommended every two years.

Smoking, obesity and physical inactivity also are risk factors.

Once you know your risk factors, you and your doctor can complete a risk assessment and determine what steps, if any, need to be taken.

During midlife, the risk of heart disease and heart attack jumps dramatically. But almost 95 percent of women who die of heart disease have at least one risk factor that could be reduced through lifestyle changes or medical care. By taking action, women can reduce the risk of heart-related problems that endanger their health.