Dear Dr. Roach: I have been diagnosed with thyroid antibodies. What are the long-term effects of these antibodies? The doctor says to start thyroid medication.
I have been a vegetarian since 1983 and have a low-salt diet. I have heard about quality control issues with thyroid medicines and taking care not to consume caffeine with the medicine.
Could my diet be related to the antibodies? Are there real problems with the production and timing?
R.S.
In general, thyroid replacement medication is most often given to people who have symptoms and laboratory evidence of low thyroid hormone (hypothyroidism). These symptoms can be nonspecific, such as fatigue, weight gain and depression, but there are more specific changes in the skin, eyes and nervous system that an experienced clinician can identify with a meticulously careful look through a patient’s history and an exam.
There are situations in which a person may be recommended thyroid replacement even when there are no symptoms. One instance is in people with antithyroid peroxidase antibodies. A high level of these anti-TPO antibodies predicts a high risk of developing symptomatic hypothyroidism. Many experts will treat their patients who have normal thyroid levels but also have elevated thyroid-stimulating hormone levels and antibodies. (The TSH level is not the active thyroid hormone. It’s a signal hormone from the pituitary to stimulate the thyroid gland. High TSH levels mean the pituitary gland senses a low thyroid level, except in rare instances of brain tumors causing an abnormal release of TSH.)
Overt hypothyroidism develops in about 4% of these patients per year. Anti-TPO antibodies are associated with the most common form of thyroid disease, Hashimoto’s thyroiditis — an autoimmune destruction of the thyroid gland.
A vegetarian diet does not increase risk of developing thyroid problems. A low-salt diet is healthy and, likewise, does not affect thyroid levels.
You mentioned quality control. This was a concern years ago. Many physicians continue to prescribe the Synthroid brand of thyroxine, but recent studies have confirmed that all FDA-approved manufacturers of thyroid hormone have very good quality control. Switching brands of thyroid hormone had very little, if any, effect on a person’s hormone levels measured by the lab.
For people who are very sensitive to changes in medicine, or who are on the border of needing a new dose, I generally recommend staying with the same manufacturer, even though it’s likely that the person will be fine with a different manufacturer.
Caffeine does slightly reduce absorption of thyroxine, so avoiding caffeine within 30 to 60 minutes of taking thyroxine is standard advice.
Dear Dr. Roach: What is it within a person’s gut that causes smelly burps?
N.N.
Eructation, the medical term for a burp or belch, is the release of air from the stomach — virtually all of which is swallowed while eating and drinking. The odor of a belch then comes from what a person had eaten.
However, there are rare times when gas produced by intestinal bacteria can get all the way up into the stomach in people with abnormal movement of the gut, such as gastroparesis. This can also happen in a person with an abnormal connection (an internal fistula) between the stomach and a different part of the gut, such as the colon; in a person with inflammatory bowel disease; or in a person with cancer. This is, fortunately, quite rare.
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to [email protected]
