Originally Published in
the American Naturopathic Medical Association Monitor

Nutritional Interventions for the Thyroid

Robert Thiel, Ph.D., Naturopath, Director of Research, Doctors’ Research, Inc.

Dr. Thiel runs a clinic in Arroyo Grande, County of San Luis Obispo, California.

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Abstract: People who have symptoms associated with hypothyroidism or hyperthyroidism do not always test positive for thyroid conditions when thyroid panels are run. The purpose of this pilot study was to determine how often individualized nutritional interventions could result in symptomatic improvement for people who were believed to need thyroid nutrition. 217 of the 220 participants (98.6%) reported improvement in two months (p <0.01) with problems such as fatigue, depression/mood, headaches, body fat, weight, and other symptoms.

Thiel, R.J. Nutritional Interventions for the Thyroid. ANMA Monitor, 2000;4(1):6-14

INTRODUCTION

Thyroid problems, clinical and/or subclinical, are exceptionally common [1-8]. One study involving 46,000 Americans founds that 11% had one or more undiagnosed thyroid conditions [6]; a non-American study found that 9.7% of elderly males and 18.2% of elderly females had hypothyroidism [7]. Subclinical hypothyroidism, which is rarely diagnosed, is perhaps the most common problem [8]. Being female [9], smoking [10], depression [11-14], poor nutrition [15], and advancing age [1,7] are all factors for developing thyroid problems (though men, children, and non-smokers get them as well [6,7,10]). This investigator also suspects that stress may play a role as well.

It has been speculated that since ?other ions can compete with iodine? [16], water with fluoride and/or chloride may contribute to thyroid problems as these ions also may have an affinity for the thyroid gland. Also since iodine soil concentrations are low in many areas of the world, ?normal? local diets can contribute to thyroid problems [16]. Certain foods, perhaps most notably soy, have been linked to the development of hypothyroid problems, but this controversy has not yet been fully resolved [17,18] (this investigator suspects the soy-hypothyroid link is strongest when large amounts of soy have been consumed on a prolonged basis). Some foods such as cabbage, kale, kohlrabi, rutabaga, cauliflower, mustard greens, radishes, broccoli, brussel sprouts, corn, peas, lima beans, sweet potatoes, cassava, sorghum, apricots, prunes, walnuts, cherries, almonds, and bamboo shoots contain goitrogens (thyroid suppressants) and/or progoitrogens (thyroid stimulants) which, though they probably do not adversely affect persons with optimal thyroid function, may affect those with thyroid conditions if they are frequently consumed [18].

The thyroid is a small gland which produces hormones which are generally believed to speed metabolism (such as thyroxine) and affect concentrations of calcium (calcitonin) [19,20]. Symptoms associated with a suboptimal thyroid include fatigue, cold extremities, depression, mood swings, behavioral disorders, weight issues (both weight gain and inability to gain weight), circulatory complaints, hypercholesterolemia, hypertension, headaches, arrythmias, lower tolerance for temperature fluctuations, menstrual problems, dry skin, and constipation [19,21,22]. Poor nutrition has been positively correlated to low serum thyroid hormone levels [15]. Natural health practitioners have long worked with nutrition and the thyroid. Nutritional support has been used in the U.S. since at least 1916 [23] and in China since around 3000 B.C. [24]. A clinical trial was performed to determine how often individualized nutritional interventions would result in symptomatic improvement for people suspected to need thyroid nutrition.

SELECTION CRITERIA

Subjects were eligible for inclusion in this trial if they agreed to provide (and did provide) feedback, signed a consent agreement (or in the case of minors, their guardians provided consent), followed the recommendations for two months, and indicated that they suffered from symptoms associated with a suboptimally functioning thyroid. 220 people were eligible and participated: 141 were female and 79 were male. Ages ranged from 3-90; the mean participant age was 45.0 years.

METHOD

After completing the selection documentation, all subjects were interviewed for approximately 45 minutes. All subjects were then assessed using Reflex Nutrition Assessment (RNA). RNA is a non-invasive technique used to assess nutrition status and possible food intolerances by observing the responses of muscles under externally provided human force [25]. Subjects were only included in this trial if RNA confirmed a nutritionally-deficient thyroid gland. Participants who appeared to be intolerant to one or more foods (such as those containing caffeine) were advised to avoid them. Participants were advised to consume an average of three tablets per day of one or more nutritional supplements. Although the actual supplements varied by individual, they tended to include various herbs (such as kelp, alfalfa, burdock, scullcap, and dong quai), minerals (such as iodine, selenium, and chromium), amino acids (such as tyrosine), polysaccharides (containing the eight essential monosaccharides [26]), and/or bovine glandulars (primarily thyroid, pituitary, liver, and adrenal). Subjects were interviewed (and body fat measured) at approximately one month intervals to determine change. Body fat measurement was usually based on electronic bioimpedance measurement (other methods, such as calipers, were used for those that our bioimpedance scale could not calculate--mostly those weighing over 250 lbs.).

RESULTS

217 participants (98.6%) orally reported improvement within 60 days; the p value of improvement (using a binomial Fisher’s extract test) was <0.01. Reflex assessment indicated that 91 of participants in this study (41.4%) were negatively affected by caffeine. Improvement was tabulated for loss of body fat, weight gain (for those unable to gain weight), mood/behavior issues, headaches, arrythmias, and circulation. Improvement was noted (but not tabulated) for reduction of dry skin, constipation, menstrual problems, hypertension, improved appetite for vegetables, hypercholesterolemia, and sex drive (in woman). 193 participants (87.7%) reported significant improvement, 24 participants (10.9%) reported minor improvement, and 3 participants (1.4%) reported no improvement. Age and gender were not found to be significant factors affecting improvement. Thus toddlers (the youngest subject was 3) and elderly seniors (the oldest subject was 90), as well as ages in-between, appeared to benefit from nutritional support for the thyroid. The average participant had 2.4 symptoms associated with suboptimal thyroid functioning.

The 3 participants which showed no improvement had only one thyroid-related problem each (2 who needed to lose body fat and did not during the two months and 1 who wanted to gain weight did not gain weight during the two months--though he did gain it later). 114 of 116 (98.3%) with mood/depression/behavioral problems reported improvement. 128 of 130 (98.5%) with fatigue/tiredness reported improvement. 60 of 61 (98.4%) with headaches reported improvement. 18 of 19 (94.7%) with various arrythmias reported improvement. 35 of 37 (94.6%) with circulatory complaints reported improvement. 8 of the participants had been taking thyroid medications before and during the trial--all these 8 reported improvement. Some participants reported less dry skin, easier menstrual cycles, reduced cholesterol levels, improved blood pressure, less constipation, less desire for alcohol, less desire for tobacco, increased desire for vegetables, decreased desire for coffee, and (for many women, but only one man) improved sex drive, but statistics were not collected by individual symptom.

Body fat measurement was used in this trial instead of weight loss as many who attempt to lose weight sometimes gain muscle through exercise and because ?all aspects of fat metabolism are enhanced under the influence of thyroid hormone? [20]. The mean loss of body fat for the 115 participants who needed to lose fat was 1.3%. 69 of 115 (60.0%) lost body fat during the two month trial with an average loss for them of 3.5%, 10 (8.7%) showed no change in body fat, but 36 (31.3%) gained an average of 2.6% of body fat. 44 of the 46 (95.7%) who gained or had no change in body fat had other symptomatic improvement. On the reverse side, 11 of 12 (91.7%) who desired to gain weight, gained weight.

DISCUSSION

Two studies concluded that 6-10% of the population suffers from subclinical hypothyroidism [4,8] while another concluded that up to 48% of U.S. and U.K. seniors (over age 60) had subclinical hypothyroidism [1]. While some consider subclinical hypothyroidism to be a condition diagnosable from serum TSH (thyroid stimulating hormone) tests [27], in this investigator’s opinion, true subclinical hypothyroidism is not diagnosable from blood tests, but by symptoms only. Since thyroid blood tests do not always reveal that thyroid may be involved, actual symptoms can be much more significant factors in determining whether a nutritional intervention may be effective; other doctors have reached similar conclusions [3,5,11,28]. There is a major medical debate about what to do about subclinical hypothyroidism [5,29,30]--the major points are that subclinical hypothyroidism exists, but that there are negative consequences associated with synthetic thyroxine replacement therapy as it leads to thyroid atrophy and dependency [5,9,30]. Doesn’t nutritional support appear to be the logical choice in such situations? Thyroxine is sometimes prescribed in a specific effort to induce thyroid atrophy [31]; even when that is not the goal, synthetic thyroxine does not nutritionally support the thyroid gland.

A Dutch study found that synthetic thyroid therapy helped only 25-30% of those with subclinical hypothyroidism [8], yet three previous studies performed by this investigator found that the use of non-medical, nutritional thyroid interventions resulted in more than 95% reporting improvement [32-34]. Thyroxine therapies are suspected to increase the incidence of the nutritional problem of osteoporosis [35-39]. It may be because they interfere with estrogens or it may be that the atrophy of the thyroid gland leads to a reduced production of calcitonin or other substances [4,40]. Studies show that food source calcitonin appears to improve bone density in both males and females who suffer from osteoporosis [40,41]. Actually, one study found that bone loss was reduced by approximately 65% for women who took food source calcitonin and calcium compared to women on estrogen/progesterone therapy as well as for women on twice as much calcium alone [41].

Since everything is not known about the thyroid gland [31] or its nutrition [16], this researcher believes that a comprehensive nutritional approach to support the thyroid gland is much more likely to improve overall nutritional health and metabolism than any hormone therapy. Synthetic thyroid hormone therapy leads to dependency [31], which should not be necessary in cases (such as subclinical hypothyroidism) where the thyroid is capable of producing hormones. That is not to say there is no place for hormone therapies (there clearly are [31]), but nutrition-based approaches may be the key to improving the health of those who suffer from nutritionally-deficient thyroid glands [3,18,32-34,42,43]. It is well known that thyroid problems are much more common in women than in men [6,9]. Oral contraceptives (birth control pills) can trigger and even be the cause of migraine headaches [3,31]. This investigator believes this is because they raise estrogen levels to the point they negatively affect estrogen-thyroid hormone balance (these hormones seem to work together in a manner which affects behavior [40]) and that this subsequent imbalance can ultimately result in a suboptimally functioning thyroid. It is also this investigator’s clinical experience that women who take estrogen-containing compounds tend to need nutritional support for the thyroid longer than others do (often indefinitely).

The primary thyroid hormone is made up of iodine and tyrosine and undergoes several metabolic processes to become T-4 (commonly called thyroxine) and T-3 (triiodothyronine) [16,20]. Many foods contain iodine (such as sea vegetables) and protein-containing foods contain between 1.4-5.8% tyrosine by mass [43]. The thyroid must trap about 60mcg of iodine each day to maintain an adequate amount of thyroxine and at least one billion people living in developing countries are currently believed to be deficient in it [16]. Herbs, such as kelp, alfalfa, dong quai, scullcap, burdock, and kelp, have been used to help support the thyroid [44-46]. Herbs contain minerals and phytonutrients which appear to support proper thyroid functioning (though too much kelp can be a problem [47,48]). Kelp has a high concentration of food complexed iodine [16] and has been used for thyroid health for at least 5,000 years [24] (most of the iodine in this trial came from kelp). Kelp may also affect TSH levels as well [48]. Some natural health professionals have found that chromium can support thyroid health [49] and this study included chromium GTF in a vegetarian natural food complex. Glycoproteins are necessary for TSH and are made from proteins and eight essential monosaccharides (in this trial they were included as part of a polysaccharide complex) [26,50]. It is known that the thyroid needs minerals such as selenium, zinc, and iodine. Although those minerals were not used separately in this trial, it should be noted that glandulars contain the about the highest concentration of selenium of any food [51], organs contain good amounts of zinc [52], and the thyroid glands contain the highest concentration of iodine in the body [16]. Glandulars also contain peptides, amino acids, and other substances which are believed to help support the thyroid [18,53-58]. Dr. Cass Ingram (D.O.), has written that synthetic approaches to thyroid problems (such as Synthyroid), have little, if any, effect on headaches; he prefers natural glandulars [3].

The results in this trial associated with improved mood/depression/behavior [33], fatigue [34], and migraine headaches [32] were consistent with this investigator’s research in these areas. The improvement in arrythmias and circulatory concerns is consistent with this investigator’s earlier clinical observations in those respective areas. Many people with fatigue appear to have clinical or subclinical hypothyroidism [34,59]. Perhaps more significantly, many people with depression or other cognitive disorders appear to have clinical or subclinical hypothyroidism [11,13,14]. Many of these people appear to be resistant to standard treatments for depression, unless the thyroid is also addressed (which it often is not) [11,13,14]. Is it necessary for so many people to suffer a reduced quality of life when nutritional support for the thyroid can help?

Weight was the one area where results, though positive overall, were quite mixed. This may be because weight and body fat could have more facets to them than most of the other symptoms that were monitored. Some subjects lost body fat while making no lifestyle changes, yet some gained body fat though exercising and dieting. This researcher suspects, however, that the combination of exercise, diet, and thyroid support results in permanent body fat loss better than any one of them separately (genetics, infections, and other factors probably also play a role). It should be noted that this trial was limited to a two month period and that it may, in some cases, take longer for nutritional support of the thyroid to have a noticeable effect in this area.

Caffeine was suspected to play more of a negative role in this study than any other single food substance. Dr. Alex Duarte places caffeine first in his list of foods which can cause migraine headaches [60]. Just like thyroxine [19,20], caffeine increases the metabolic rate [61] and can positively affect mood [62]. A military study concluded that caffeine intoxication usually occurs with consumption in excess of 250mg [63]; this investigator believes it takes much less caffeine to affect women. This investigator also speculates that some people who need nutritional thyroid support will use caffeine in an attempt to compensate for the positive feeling increased metabolism often gives. Perhaps not surprisingly, caffeine is the most widely consumed pyschotrophic drug [62].

In the U.S., most (around 75%) caffeine is consumed through coffee, followed by tea and sodas [64]. Caffeine is in many commonly consumed ?foods? as follows [65]: 5 ounce glass of ground roasted coffee 85mg 5 ounce glass of instant coffee 60mg 5 ounce glass of decaffeinated coffee 3mg 5 ounce glass of tea (1 leaf bag) 30mg 5 ounce glass of instant tea 20mg 5 ounce glass of hot chocolate/cocoa 4mg 6 ounce glass of cola 18mg 6 ounce glass of chocolate milk 4mg 1 ounce of chocolate candy 1.5-6mg Interestingly, caffeine seems to have an antioxidant effect [66]. This is probably one of the reasons that caffeine seems to relieve headaches in many [22] (another could be that caffeine may irritate the nervous system which results in temporary dilation). This investigator, though, suspects that the consumption of caffeine becomes a vicious cycle--it probably temporarily relieves, but ultimately contributes to additional migraine headaches. Its consumption also probably delays sufferers from seeking nutritional help for thyroid issues, since this investigator believes that caffeine may mask certain hypothyroid conditions (such as mood and fatigue issues). Withdrawal reactions occur in 25-100% of coffee consumers and includes severe headaches, depressed mood, anxiety, and fatigue [63]. Caffeine withdrawal headache symptoms usually occur between 13 to 23 hours of discontinuing caffeine and it occurs most frequently with heavy consumers of caffeine [67]. The reality is that more money is spent promoting caffeine and performing research in support of caffeine than is spent to warn consumers about caffeine [68].

CONCLUSION

Since thyroid problems are common, most traditional health professionals believe that they require management with external agents to reduce their occurrence [11,31]. While this investigator concurs with this belief in many cases, is it necessary that these agents be synthetic? This investigator is concerned that long-term use of many of the medications used to treat thyroid conditions can result in atrophy of the thyroid [31]. Thus it seems clear that other interventions should be considered, at least as an adjunct. Natural interventions administered by properly trained professionals tend to have fewer negative consequences (pregnancy and other cautions, though do apply) than the synthetic counterparts offered by some practitioners [31]. Food and nutritional problems do contribute to causing thyroid problems [15,16]. As this trial confirmed with 217 of 220 reporting improvement, nutritional approaches appear to be helpful to improve symptoms associated with suboptimal thyroid health. This researcher encourages doctors and health researchers to be willing to challenge current paradigms about the thyroid and to work toward cooperative interventions to help those with thyroid concerns improve and lead better lives.

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