Dear Doctor: I saw my doctor because my heart was beating funny and I was losing weight even though I wasn’t dieting. She did a blood test, and it turns out to be Graves’ disease. Why did I get that? Is there a cure?

Dear Reader: When someone has Graves’ disease, it means a malfunction of their immune system has caused their thyroid gland to become too active. Known as hyperthyroidism, it’s a condition that causes the overproduction of thyroid hormones. Since these hormones play an important regulatory role in many parts of the body, the symptoms of Graves’ disease can be quite varied.

The thyroid is part of the collection of glands located throughout the body known as the endocrine system. Their job is to produce hormones, which are chemical messengers. They regulate bodily processes such as metabolism, sleep, mood, growth and development, reproduction, tissue function and sexual function, to name just a few.

The thyroid itself is a small gland. It weighs less than an ounce and is shaped roughly like a butterfly. It’s located at the base of the throat, just below the larynx, and consists of a pair of matching lobes that sit on either side of the windpipe. The thyroid takes the iodine in our diet and manufactures two main hormones, which help regulate vital functions throughout the body. These include heart rate, body weight, body temperature, muscle strength, breathing, cholesterol levels, the central and peripheral nervous systems, and in women, menstrual cycles. So you can see how any malfunction of the thyroid can have a wide-ranging effect on general health.

When it comes to Graves’ disease, the cause is unknown. It usually develops before the age of 40, and is more common in women than in men. People with existing autoimmune disorders are at increased risk of developing Graves’ disease, and family history can play a role. Cigarette smoking is a risk factor, as well.

Symptoms of Graves’ disease include the unexplained weight loss and irregular heartbeat that you experienced, as well as anxiety or irritability, sleep disturbance, fatigue, reduced libido, sensitivity to heat, and tremor in the fingers or hands. Some people develop Graves' ophthalmopathy, which is a collection of eye-related symptoms such as pressure, grittiness, light sensitivity and vision problems. Graves’ dermopathy, which is rare, causes the skin on the shins or tops of the feet to thicken and become red.

Diagnosis is via blood tests to determine thyroid hormone levels, imaging tests to look at the size of the thyroid or tests that assess the rate at which the thyroid is using iodine. There is no cure at this time. Instead, treatment focuses on slowing thyroid activity. This can be achieved through radioactive iodine therapy, which gradually destroys overactive thyroid cells; medications that either interfere with the thyroid’s ability to produce hormones or block the effects of thyroid hormones on the body; or thyroid surgery. Lifestyle changes such as a healthful diet, regular exercise and doing what you can to ease stress are also important for managing the condition. Complications can be serious, including heart disorders and problems during pregnancy, so it’s important to seek treatment.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I live alone, and stay-at-home orders have been hard. I’ve heard people say that being lonely is really bad for your health, and now I believe them. What problems can it cause? Also, I’m going to start seeing friends and family again. What can we do to stay safe?

Dear Reader: While it’s easy to understand the link between loneliness and depression, anxiety and other psychological ills, the connection to physical effects on the human body can seem like a bit of a stretch. However, ongoing research has shown that loneliness, as well as the social isolation we have all been asked to practice for several months now, do, indeed, take a physical toll.

Individuals who experience chronic loneliness have been found to be more vulnerable to a number of diseases and conditions than are people who enjoy strong emotional connections. These include an increased risk of developing heart disease, metastatic cancers and having a stroke. Older adults who are socially isolated are also more likely to become cognitively impaired or to develop dementia, including Alzheimer’s disease. Researchers have even tied loneliness to an increased risk of premature death. Adults in midlife who are chronically lonely are 25% more likely to die prematurely. Older adults, whose social connections have shrunk due to factors such as retirement, have double the risk of premature death as those who are socially connected.

You’re not alone in being determined to rekindle your social contacts. We’ve all seen an increase in the number of people returning to a semblance of normal life. The challenge is that each and every contact with someone outside of your quarantine circle becomes a calculated risk. This is because of the highly transmissible nature of the novel coronavirus and the existence of asymptomatic carriers, who can unknowingly pass along the virus. Still, several months into the pandemic, the medical community has gained a clearer understanding of mitigation measures. As a result, the focus has begun to shift from strict quarantine behavior to risk management and mitigation.

Before we go any further, we have to repeat that any contact with people outside your quarantine circle puts you at risk of infection. The best way to lessen that risk is to stick to small gatherings that are held only outside -- never indoors. And it’s crucial to maintain the social distancing guidelines we are all now familiar with. That means tables or chairs or picnic blankets spaced at least 6 feet apart. No handshakes or hugging, no matter how tempting it may be. Everything about the gathering should be BYO -- bring your own. That includes food, drink, condiments, disposable plates, cups and utensils, and a large garbage bin for safe disposal. Wear masks except while eating or drinking. No sharing of food or drink or condiments. If things get lax and you become uncomfortable, make a polite excuse and leave. This is all a far cry from the way we visited with each other in the pre-COVID-19 world, but the potential consequences of skipping or relaxing even one of these steps are too grave.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Hello, dear readers, and welcome to our first letters column of the summer. We’ve had a lot of mail -- thank you! -- so we’re diving right in.

-- Let’s start with a question regarding two essential tools of outdoor summer living -- sunscreen and insect repellent. A number of you have written to ask how long these products remain effective. It’s true that most don’t include an expiration date on the packaging. However, the Food and Drug Administration requires sunscreen to maintain its original efficacy for at least three years. (Of course, that means you’ll have to remember when you made your purchase.) Most manufacturers say their insect repellents remain effective for two to three years. If you need a more precise answer, you can call or email the manufacturer’s customer service department and provide them with the lot number of the product you’re asking about.

-- A column about the unhealthful nature of processed foods puzzled a reader from Iowa. “Can breakfast cereal, which is extruded, molded and milled, be considered a healthy processed food?” she asked. The answer is that it depends on the specific cereal. Those that are made from whole grains, have little-to-no added sugar and salt, and are high in fiber can be considered healthy-ish. (Emphasis on the “ish.”) Eat them with a serving of fresh fruit, watch portion size and don’t dip into the sugar bowl. Cereals fortified with vitamins, minerals and iron can contribute to daily nutritional goals.

-- A reader in Virginia thought we left out an important detail in our discussion of preventing deep vein thrombosis, which is the formation of blood clots, on long plane flights. “Never once did you mention wearing compression socks on the flight,” he wrote. “Doesn’t that help prevent DVT?” You’re correct that wearing compression socks or stockings can help reduce the risk of developing deep vein thrombosis. According to the National Institutes of Health, about 2 out of every 10,000 passengers develops DVT on a long flight. For those at high risk, knee-high compression stockings with compression strength between 15 and 30 mmHg are a good idea.

-- We received a lot of mail in response to a column about the importance of vitamin B12, an essential vitamin the body needs but doesn’t produce. The answers to your varied questions are: B12 is manufactured by bacteria living in the guts of a variety of mammals, fish and poultry. It’s available in animal products, including fish, meat, poultry, eggs, milk and milk products. It’s also available as a supplement, both over-the-counter and through prescription. OTC products, although not regulated by the FDA, are considered to be a reliable source of the vitamin. Studies have found no advantage of sublingual (under the tongue) B12 over tablet form. Most B12 supplements exceed the recommended dietary allowances (RDA) for adults of about 2 to 3 micrograms per day. However, the body absorbs only as much as it needs, and any excess of the water-soluble vitamin is excreted in the urine.

Thank you to everyone who wrote with kind words. We’re thrilled that you continue to find this column both interesting and useful. We look forward to seeing you again in this forum next month.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)