Caffeine, Calcium and the Thyroid
Nutritional Linkages to Thyroid Disease and Thyroid Drugs
Caffeine is a stimulant, and has an effect on your central nervous system, your digestive tract, and your metabolism. Also according to Intellihealth, "in high doses, caffeine can cause rapid heartbeat, irritability, insomnia and anxiety in some people."
Caffeine has at times been associated with various illnesses, such as heart disease, infertility miscarriage, and fibrocystic breasts. While there's strong evidence that caffeine has major effects on both body and mind, however, there's a lack of clear scientific evidence to prove the cause-and-effect nature of some of the relationships with diseases.
So when it comes to thyroid disease, there's a question as to whether caffeine is a drug of particular concern to many thyroid patients. Anecdotal information from a number of site visitors -- and my own experience as well -- points to the fact that caffeine can potentially be a factor that worsens symptoms.
One regular poster at a Thyroid Bulletin Board had written about the symptoms she assumed were her thyroid problem:
"The symptoms I was experiencing were not thyroid related, just as the docs said, but the result of excessive coffee consumption. I only found this out after stopping all coffee consumption about six weeks ago. Some of these symptoms are very similar to thyroid disease symptoms and since I did have thyroid disease that is the area I explored. A very easy mistake to make especially since caffeine containing products are promoted as innocuous beverages...Ever since stopping a 25 yr. ten cup minimum per day coffee habit all my adverse symptoms, and there were many, have stopped. Today I feel perfectly normal."
As she found out, some of the symptoms of too much caffeine can mirror undertreated or untreated hyperthyroidism and hypothyroidism. Symptoms include: restlessness, nervousness, excitement, insomnia, flushed face, frequent urination, stomach disturbance, muscle twitching, rambling flow of thought and speech, fast heartbeat or cardiac arrhythmia, and more. And caffeine, like many stimulants, can be very problematic for someone with untreated hyperthyroidism, or who is in the process of receiving treatment for hyperthyroidism.
More information on caffeine symptoms is available in the Caffeine FAQ.
In addition to similarity of some symptoms, there is a suspected hormonal relationship between the thyroid and caffeine. According to researchers, "Caffeine has been shown to markedly alter...thyroid stimulating hormone (TSH), and thyroid hormones in animal studies. Similar studies in the human are lacking." (Dev Pharmacol Ther 1987;10(2):73-80) Other researchers found that "chronic caffeine therapy," constituted by high levels of caffeine use over time, "stimulated both T4 and TSH; however, TRH-stimulated TSH release was decreased, suggesting that chronic therapy may blunt pituitary TSH response." (Pediatr Res 1983 Jul;17(7):592-595).
Recognizing that caffeine may impact the thyroid's ability to function, therefore, is enough reason to consider cutting out or cutting down on caffeine.
Let's look at a few other things we do know about caffeine and thyroid-related symptoms.
We now know know that hypothyroidism is a major contributing cause to many cases of carpal tunnel syndrome (CTS). And for those people with hypothyroidism who suffer from this debilitating CTS wrist/arm/finger pain, it's been found that caffeine is a also a possible culprit in aggravating carpal tunnel syndrome.
Another reader, Ron, wrote regarding his carpal tunnel syndrome and caffeine. He writes:
So if carpal tunnel, or other nerve and swelling-related problems are plaguing you, you might want to consider cutting out the caffeine.
Here is a chart of the caffeine content of your favorite beverages:
It's known that caffeine causes urinary excretion of calcium. The Journal of the American Medical Association (JAMA) (JAMA, 26 Jan. 1994, p. 280-3) found that "There was a significant association between (drinking more) caffeinated coffee and decreasing bone mineral density at both the hip and the spine, independent of age, obesity, years since menopause, and the use of tobacco, estrogen, alcohol, thiazides, and calcium supplements [in women]. The decreased bone density could be offset for women who drank milk on a daily basis."
So, from the thyroid disease perspective, many of us are aware that hyperthyroid TSH levels, or overdosage of thyroid hormone into hyperthyroid levels can sap the body of calcium, and increase the risk of osteoporosis. There is also controversy over whether or not treatment with thyroid hormone that puts patients' TSH in the low-normal range can increase the risk of osteoporosis as well. Thyroxine and calcitonin are secreted by the thyroid gland, so a thyroid gland that has either been surgically removed, or is not fully functional, can inhibit bone mineral metabolisim and negatively affect bone mineral density. (Chung Hua Chung 1996 Jul;18(4):308-309 ).
But even with the various controveries, it's clear that most women with thyroid disease should already be paying special attention to fulfilling their calcium requirements in order to avoid the potential of an increased risk of osteoporosis.
Groundbreaking research reported in the American Journal of Obstetrics and Gynecology showed that calcium may ease premenstrual syndrome (PMS) symptoms. The study found that women who take approximately 1,200 milligrams of calcium each day for approximately three months can reduce many symptoms of PMS by more than half. Doctors claim that that calcium works on all groups of symptoms, including headaches, food cravings, mood swings, pain, depression symptoms, and bloating. It is difficult to obtain 1200 mg of calcium simply from diet, so doctors were recommending a serving of a low-fat milk product, plus two or three tablets of a chewable calcium supplement, such as Tums. Lead investigator, endocrinologist Susan Thys-Jacobs, believe that there may even be a link between PMS and osteoporosis. Calcium depletion may interact with the female hormones estrogen and progesterone at certain stages of the menstrual cycle, leading to the physical and emotional discomfort of PMS. Says Thys-Jacobs, "We think women are being given a signal by the body that they are not taking in enough calcium.''
So now that calcium is suspected to affect hormonal balances in the body, it's interesting to speculate on whether there could be a relationship between calcium deficiency and the worsening of "thyroid" symptoms during the PMS phases of a woman's cycle.
"We think women are being given a signal by the body that they are not taking in enough calcium.''So, in addition to seriously considering calcium supplementation, both to prevent osteoporosis, alleviate PMS, and potentially help have a positive effect on hormonal balances, when you consider that caffeine saps the body of calcium, it's another argument for considering eliminating or severely restricting your caffeine intake at the same time.
All information is intended for your general knowledge only and is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician or health practitioner before starting a new treatment program. Please see our full disclaimer.