Dear Doctors: A friend who has Parkinson’s disease is starting to have trouble swallowing. Can you explain why that is? I thought Parkinson’s mainly affects the hands and limbs. Also, she and her husband are often dinner guests at our home. What foods are easiest for her to manage?

Dear Reader: Parkinson’s disease is a progressive neurological disorder in which ongoing changes in the brain affect and interfere with movement. This occurs due to a disruption in the production of dopamine, a neurotransmitter that is essential to smooth and continuous muscle movement. Although the cause of the disease is not yet known, an emerging body of research suggests a link to the microflora of the gut microbiome.

The physical effects of Parkinson’s disease include the onset and gradual worsening of symptoms such as resting tremor, muscle stiffness and rigidity, slowed movement, muscle weakness, poor balance and diminished motor coordination. You are correct that these are most noticeable in the hands, arms and legs. However, muscle weakness and loss of motor control often also affect the jaw, mouth, tongue and trachea. This makes it difficult to chew food properly and impairs swallowing.

Difficulty in swallowing, which is common in Parkinson’s disease, is a condition known as dysphagia. Symptoms include struggling or being unable to swallow, incomplete swallowing, a sensation that food is stuck in the throat, coughing or gagging during a swallow, regurgitation and heartburn. Some people may experience drooling or develop a hoarse voice. Dysphagia also increases the risk of aspiration, which is when food accidentally enters the airways.

People living with Parkinson’s disease face several challenges when eating. One is the motor control needed to select a bite of food and carry it to the mouth. Many find that using a large spoon, or even their fingers, makes this easier. You can ask your friend, or her spouse, if she has a preference in tableware. You can provide her with a tablespoon or make it clear that you would be happy to include her own cutlery in the table setting. Because coughing and drooling may occur, be sure to provide her with several large and absorbent napkins.

When someone has trouble swallowing, foods that are soft and moistened are easiest to manage. You might consider a stew, which typically consists of fork-tender, bite-sized pieces. A soup made with pureed vegetables would offer the thicker consistency that is both easier and safer for someone with dysphagia than a thin liquid. Grilled or broiled fish is both easy to chew and nutritious. If you serve side dishes such as rice or potatoes, include a sauce to moisten them.

You can also make sure that the food on your friend’s plate is already cut into smaller pieces suitable to be grasped with the fingers or slipped into a spoon, and easier to chew. This can all be done quietly and without fanfare. No one will notice the extra steps you have taken, and your friend will have a more enjoyable -- and safer -- meal.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctors: I am a 47-year-old woman in good health. I exercise regularly and eat a healthy diet. At my physical, I was surprised when my doctor said I have A-fib. I have never felt anything wrong with my heart, so I am confused. Can you please explain A-fib?

Dear Reader: You are asking about a heart condition called atrial fibrillation. Often referred to simply as A-fib, it is a type of heart arrhythmia. The heartbeat we rely on to circulate blood throughout the body is made up of a precise series of rhythmic contractions. This includes the timing of the heartbeats, and the slight pause between them. If any element of this series goes awry for even a short period of time, it is known as an arrhythmia.

To better understand, we should start with a bit of anatomy. A healthy adult heart is roughly the size of a clenched fist and resembles an inverted pear. It is divided into four chambers, two above and two below. The lower chambers are known as the left and right ventricles. The two on top, which are the ones involved in the arrhythmia you have been diagnosed with, are called the left and right atrium.

The right atrium and right ventricle work together to receive the blood that has just traveled throughout the body and move it into the lungs. There, it gets topped off with oxygen. The left atrium and left ventricle work together to receive the now-oxygen-rich blood exiting the lungs and to send it off to the tissues of the body.

When someone has atrial fibrillation, it means the two upper chambers of the heart have ceased to function properly. It occurs due to a malfunction in a cluster of cells in the right atrium, known as the sinus node, which send out the electrical signals that regulate heart rhythm.

Rather than producing the strong and coordinated contractions needed to move blood through the heart valves and into the ventricles, the atria behave erratically. This can include beating too fast, making quivering and incomplete contractions, failing to pause between contractions and beating out of sync with the ventricles below. The result is a chaotic heartbeat that stalls the flow of blood through the heart. It can cause blood to pool in the atria, which can clot. This, in turn, raises the risk of a stroke. In 15% to 20% of strokes, A-fib is a factor.

As has happened with you, not everyone with A-fib develops symptoms. When they do manifest, symptoms can include a fast and irregular pulse, a fluttery sensation in the chest, general fatigue, unusual fatigue when exercising, shortness of breath, dizziness and weakness. Reduced blood flow in the heart can cause angina, which is chest pain or a sensation of pressure.

The fact you are not experiencing symptoms does not mean this diagnosis can be ignored. Treatment typically includes identifying the reason for the condition, reducing stroke risk and using medications or appropriate procedures to restore normal heart rhythm. It would be wise for you to follow up this diagnosis with a cardiologist.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctors: Like a lot of people, I’ve had to return to the office. At home, I did calls and meetings on the treadmill, walked at lunch and lifted weights during breaks. That’s not possible now. I know sitting is bad for your health. Can you discuss the research? I’d like to share it with my boss.

Dear Reader: Whether you work at a desk, enjoy leisure activities from a couch or mainly use a car to get from one place to another, modern Americans spend more time sitting than at any point in history. For many, the total is well over 10 hours of sitting per day. That’s the number that research associates with a marked increase in cardiac risk. And for bodies built for motion, this shift has proven to be a significant threat to health.

These long stretches of sitting play a significant role in weight gain, obesity, loss of lean muscle mass, rising body fat percentage, increases in abdominal fat, hypertension and poor blood glucose control. These, in turn, translate into an increased risk of developing diabetes, a wide range of cardiovascular diseases, cancers and early death.

Mental health takes a hit as well. A sedentary lifestyle is associated with an increased risk of anxiety, depression and changes to cognition. Small wonder that the prolonged inactivity that marks modern life has come to be referred to as “sitting disease.”

The newest study into the potential health dangers of being sedentary comes from researchers in Australia. Interested in whether prolonged sitting might be associated with an early death, they analyzed 14 years of health data gathered from 5,836 middle-aged adults. They found the risk of death from any cause was 47% higher among people who were sedentary than those who were active.

We are happy to be able to balance this sobering news with research looking at the question from the other perspective. That is, the positive effects on physical health of being active. A study in the British Journal of Sports Medicine analyzed the health outcomes of 44,300 women and men whose lifestyles ranged from completely sedentary to moderately active. The researchers found that even brief sessions of daily exercise helped ease the adverse effects of prolonged sitting. However, the greatest benefit came from doing 35 minutes of exercise at moderate intensity per day. Interestingly, additional research shows this doesn’t have to occur all in a single session, but can be broken up into smaller increments if needed.

In another interesting study, researchers at the University of Chicago found that using a small exercise device located under their desks can be beneficial for seated workers. Known as a HOVR, it’s basically a leg swing that keeps the person’s lower body in motion. Workers using the HOVR burned almost 20% more calories than those who sat still, and 7% more calories than those at standing desks.

In an era where 80% of jobs are sedentary, finding ways to be active at work is critical to good health. We hope sharing this information with your boss will prove helpful.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)