Low thyroid function may be a factor in weight gain despite ‘normal’ tests

When I was studying medicine I was even more cynical than I am now and so, I think, were quite a few of my friends. We had all established firmly in our minds the notion that eating few calories than the body ‘burned’ would result in weight loss, so generally had little compassion for individuals who claimed they did not overeat but still could not shift their excess weight. Also, around the time a study was published which claimed that the overweight tend to significantly underestimate the amount they eat. So, if someone claimed that they thought they had a ‘sluggish metabolism’ or had ‘a problem with their glands’ (low thyroid function) then our eyes would usually roll skywards, if not outwardly, then at least inwardly.

Age, experience and new belief that being an advocate to my patients is generally important has taught me better. I have had many, many experiences over the years which have convinced me that it is possible for individuals to gain weight while eating relatively little. Not uncommonly, the problem appears to indeed lie in a under-par metabolism, which itself is often the result of a genuine problem with the thyroid gland.

Conventional assessment of the thyroid usually involves blood tests to measure thyroid hormone levels. For a variety of reasons, though, these tests will not always pick up an underlying problem. To understand how this can be, we must first understand the physiology of the thyroid gland and the function of the chief thyroid hormones:

The thyroid produces a variety of hormones, the most plentiful of which is known as ‘thyroxine’ (also known as ‘T4’). Outside the thyroid, T4 is converted into another hormone called tri-iodothyronine (also known as ‘T3’). T3 is actually a more active form of thyroid hormone. T3 basically stimulates cells to burn fuel with oxygen to release energy, some of this being released as heat. Essentially, the more T4 and T3 there is around, the faster metabolism, the less tendency there is for weight gain and the warmer the body is.

The thyroid’s production of hormones is itself regulated by a tiny gland located at the base of the brain known as the ‘pituitary’. The pituitary is itself regulated by a part of brain known as the hypothalamus. In health, if the hypothalamus senses a drop in the levels of T4 and/or T3, it sends a signal to the pituitary, which in turn secretes a hormone known as thyroid stimulating hormone or ‘TSH’. As its name suggests, this hormone instructs the thyroid to produce more thyroid hormones. In theory, as the thyroid hormone levels rise, the hypothalamus instructs the pituitary to produce less TSH, which ensures thyroid hormone levels do rise too much. This mechanism is designed to ensure stable levels of thyroid hormones in the body.

However, like any other gland or organ in the body, the thyroid gland can weaken. In this case, despite high levels of TSH, it may still not be able to make the amounts of thyroid hormones necessary for optimal health. This low thyroid function state is known as ‘hypothyroidism’. One of the typical symptoms of this is weight gain, though fatigue, dry skin, dry hair, hair loss, low mood, sensitivity to cold and constipation are others.

The conventional way to test thyroid function is to measure blood levels of TSH. If this is raised, this suggests hypothyroidism. The diagnosis is usually confirmed by measuring T4 levels, which are characteristically low in cases of hypothyroidism.

While the TSH test is generally seen by doctors and endocrinologists as a sensitive and accurate guide to thyroid function, the reality is that this test has a number of deficiencies.

One major issue here relates to the ‘normal range’ that is set for TSH. Normal ranges are designed to encompass 95 per cent of people. What this means is that to have an elevated TSH, one needs to be in the top 2.5 per cent of the population for TSH levels. This means that however common hypothyroidism may be, only a relatively small proportion of the population can be diagnosed using this test.

Also, as was discussed earlier, low thyroid function can be related to low pituitary function. In traditional medicine, lower than normal levels of TSH are believed to signify this. However, before the pituitary is exhausted to this extent, it is possible for it to go through a phase where TSH levels are considered ‘normal’, though thyroid function is significantly compromised. While this notion is plausible, it is generally not accepted by endocrinologists (doctors specialising in hormone-related disease).

Another problem with conventional testing is that it relies on levels of TSH and, usually, T4. If there is enough T4 in the body, the brain can sense this and feel there is no need to increase TSH production. However, T4 is not very active in the rest of the body ” it seems T3 has a more important role to play in this respect. It is therefore possible for someone to have enough T4 but not enough T3, and be hypothyroid as a result. T3 levels are rarely checked in conventional medicine. As a result, someone with low T3 levels who is hypothyroid as a result, can get missed as a result of ‘normal’ TSH and T4 levels being found.

Yet another potential deficiency of conventional thyroid testing is that while it may show the level of hormones in the bloodstream, it does not tell us how active and effective those hormones are. It is now well recognised, for instance, that individuals can become resistant to the hormone insulin (known as ‘insulin resistance’), which may eventually lead to a problem with diabetes. In contrast, the concept of thyroid hormone weakness has yet to catch on in conventional medical circles.

So, for these and other potential reasons, just because someone has ‘normal’ thyroid hormone levels, that doesn’t guarantee by any means that their thyroid function is ‘normal’ or ‘optimal’ by any means.

The idea that a normal TSH means normal thyroid function was dealt a bit of a blow recently on the publication of a study in the Archives of Internal Medicine in a group of 2407 individuals, all with ‘normal’ TSH levels. Despite having acceptable TSH levels, the higher the TSH level was, generally speaking, the greater body weight was too [1]. This study is accompanied by an editorial [2] which examines the evidence from the study, along with three other studies [3-5] which all found evidence that as TSH rises, so does body weight.

They also cite evidence that as individuals lose weight, TSH levels come down.

At first sight, all this looks like weight gain may indeed be related to ‘worsening’ thyroid function. However, if this were the case, then conventional wisdom would dictate that levels of T3 and/or T4 would decrease as TSH levels rise. However, the authors of the editorial point to evidence which shows that in the very overweight, thyroid hormone levels tend to be raised, not lowered.

One might argue therefore that what is going on here is the body is recognising that it is carrying too much weight, and is attempting to boost its metabolism through the secretion of TSH. It’s almost as if the body is recognising it needs to shift some excess weight and is asking the thyroid to ramp up its production of thyroid hormones through increased secretion of TSH. They go on to postulate a few mechanisms through which fatty tissue in the body could ‘communicate’ with the body in an effort to tell it to rev-up the metabolism.

While the mechanisms here are not certain, what I think all this shows is that the relationship between thyroid function and weight is more complex than most of we doctors would have people believe. What is more, there may be more to an individual’s belief that their difficulty in losing weight is in some way related to thyroid function. The authors of the editorial conclude that we may agree with patients who suggest such a thing by saying: It may be the thyroid but we don’t exactly know how.�


1. Fox CS, et al. Relations of thyroid function to body weight: cross-sectional and longitudinal observations in a community-based sample. Arch Intern Med 2008;168(6):587-592

2. Weiss RE, et al. Doctor�could it be my thyroid? Arch Intern Med 2008;168(6):568-569

3. Knudsen N, et al. Small differences in thyroid function may be important for body mass index and the occurrence of obesity in the population. J Clin Endocrinol Metab. 2005;90(7):4019-4024

4. Nyrnes A, et al. Serum TSH is positively associated with BMI. Int J Obes (Lond). 2006;30(1):100-105.

5. Bastemir M, et al. Obesity is associated with increased serum TSH level, independent of thyroid function. Swiss Med Wkly. 2007;137(29-30):431-434.

28 Responses to Low thyroid function may be a factor in weight gain despite ‘normal’ tests

  1. Vivienne 4 April 2008 at 7:34 am #

    I was on 150 mcg Thyroxine for a few years and not being sent for regular blood tests. Recently I WAS called in for a Thyroid blood test and the GP was concerned to find my T4 was 28.

    I have just had a further blood test, prior to, as I understand, a prescription for lower dose of Thyroxine.


  2. Cali Bird 4 April 2008 at 8:36 am #

    Very interesting reading. I once saw a nutritionist who suspected my thyroid was causing weight gain and she had me check my underarm body temperature every morning before rising. My temperature was coming out at between 35 and 36 degrees C and she said this indicated slow thyroid function. What do you think of this test?

  3. The other (non-dietician)Kate 4 April 2008 at 9:07 am #

    I first displayed signs of hypothyroidism as a teenager. I had test after test, and all the levels of T3 and T4 were low (so I was told).
    But, no doctor or specialist would prescribe thyroxine, giving one reason after another for their decision.
    My levels were very low after my second child was born and I went to see a specialist who I was told would look at this sympathetically, but she just said “Well, you have children don’t you? So it can’t be that low” – even with the results!
    I eventually was prescribed thyroxine at the age of 39. I got the results in my hand (it was private healthcare abroad) and the TSH was pretty high.
    All of this was because my cholesterol levels were dreadful (yes, triglycerides again) and they wouldn’t respond to statins (thankfully).
    So my GP there started me on thyroxine and I actually need 150 mcg per day.
    Blood sugars and triglycerides were improved (along with a low-carb diet) and I no longer felt that I had to run very fast just to stay still, in terms of weight.

    I think that doctors are/were reluctant to treat patients with obvious hypothyroidism for a number of reasons.
    Levels may improve on their own.
    Patients will get free prescriptions.
    Most are women and are looking for an excuse to blame their weight gain (or lack of weight loss)on something else (just lazy/lying).
    Not all hypo symptoms are present. The same goes for many other conditions, but too many specialists/GPs think that people should display all the range of symptoms.
    In my case, they said that it was ‘familial’ and that there was no point in treating me.

    I do hope things are better nowadays. Especially after this week’s ‘Casenotes’ on Radio 4. A specialist stated that he thought that the children of untreated hypothyroid women were at risk of having low IQs (80) and that women who have hypothyroidism should be treated.
    Again, there must be a large range of influences. My children don’t have low IQs, but I do wonder if this affected them.

    I do hope that things will improve.

  4. Harriet 4 April 2008 at 11:04 am #

    Hi, I found this fascinating as I am having my thyroid levels checked every six months because I have high antibody levels. However, despite having all the symptoms of hypothyroidism my results have remained normal apart from antibody levels going up hugely every time. I’m finding it all a bit depressing!!

  5. Jackie Bushell 4 April 2008 at 1:29 pm #

    Thank you Dr Briffa for highlighting the plight of ‘mild’ or ‘subclinical’ hypothyroids such as myself. Doctors specialising in this problem such as Dr Barry Durrant-Peatfield and Dr Gordon Skinner in the UK and Dr John C Lowe in the States believe that ‘subclinical’ hypothyroidism is massively underdiagnosed and undertreated. Furthermore, they say that its incidence is increasing fast and is likely to become just as much a major public health issue as heart disease and diabetes. They say that failure to recognise hypothyroidism is consigning large numbers of people unnecessarily to long term ill-health, in addition to wasting precious health service resources. For instance, they believe that untreated low thyroid is the real cause of many cases of depression and also of high cholesterol levels.

    These doctors treat large numbers of us who continue to have weight problems and other symptoms on the traditional ‘replacement therapy’ (which consists of giving us synthetic T4 at a dose which must be ruled by the TSH blood tests rather than our clinical symptoms). Unfortunately, they must currently practise outside mainstream medicine, since the mainstream endocrinology fraternity still does not accept their views, despite mounting evidence in the literature.

    For those new to the controversy surrounding the diagnosis and treatment of hypothyroidism, I recommend starting with the following hypothyroid sufferers’ support and information sites:
    And my own blog at http://gooddietgoodhealth.blogspot.com

    Dr Briffa, I absolutely recommend you read Dr Peatfield’s book ‘Your Thyroid and How To Keep It Healthy’, and Dr Lowe’s paper on the treatment of hypothyroidism at
    http://www.thyroidscience.com/Criticism/lowe.dec.2006/lowe.critique.T4.T4&T3.Studies.pdf. The latter is long and detailed, but explains everything that is wrong with the treatment of hypothyroidism or underactive thyroid today, and what needs to be done about it.

  6. Sheila 4 April 2008 at 2:23 pm #

    I was slim & in my early 30s when my thyroid ‘packed up’. Back then (early 80s) it took 3 weeks for tests to be processed. When the first test results came back, my GP thought they’d got it wrong as I was ‘too young’. So the process was repeated. The diagnosis/prognosis of a failing thryroid came back again. Weeks later after first presenting with the symptoms, I was put on thyroxin & levels were monitored; sure enough, it packed up completely within the year. (I consider myself lucky to have had such a good GP at the time) However, the weight did start going up for the first time in my life – despite having had 3 children. At one point in the 90s I was on 300 mcg but when I moved home, my new GP cut it to 150 & my weight shot up even further. Because of this, after a while, I increased it myself to 200mcg, which is what I am still on. – & periodic test results come back ‘normal’.

    I have been unable to resume my original much lighter weight, so wonder if it would be advisable to increase it again to, maybe, 250mcg? Your comments would be welcomed.

  7. Sally 4 April 2008 at 2:23 pm #

    Harriet: the endocrinologist who initially treated my hypothyroidism has theorized that approximately 80% of people with ‘clinical’ depression have underactive thryoids. My own experience of it was pretty miserable, including fatigue to the point where I couldn’t get through the day without a nap, and weight gain despite a net 900 calorie/day diet.

    Dr. Briffa: Are there any natural remedies and/or supplements you would recommend if you suspect/know you have an underactive thryoid? I am currently on 137 mcg Synthroid daily but still feel a little physcially and mentally sluggish from time to time, even though my blood work is all within normal limits. I did manage to lose a lot of weight (also thanks to a low-carb diet and plenty of exercise), and my hair has stopped thinning as much. Thanks.

  8. Anna 4 April 2008 at 5:51 pm #

    Excellent post! I’m one of those peri-menopausal women who probably has had undiagnosed mild hypothyroidism for more than 15 years, beginning with a sudden weight shift from chronically underweight to a few pounds overweight at age 29. In my 30s my weight crept up very slowly, and my energy level went down.

    Despite numerous routine TSH tests (my lab uses an “outdated” reference range), years of infertility, and a long list of symptoms including obvious chronically low body temps, my GP insisted it wasn’t my thyroid because of the lab results. I got a copy of my 10 years of records with her and my TSH, while technically still in the “normal range” (the upper range has been controversial and that’s where my TSH was) had steadily increased incrementally for 10+ years, as did my cholesterol levels (same exact curve and time frame, when I graphed it).

    When I switched doctors, the dose she gave me was much too low, though a couple symptoms improved (my temp raised, I perspired again, I slept better). The the new GP was happy with the new lab results and wouldn’t raise the dose, despite daily afternoon “crashes” in energy and mood. Instead she suggested an anti-depressant, which I decided not to take until I thought the hypothyroidism had truly been treated adequately.

    I finally had to go outside my HMO system and pay out of pocket to see a doctor who specializes in hypothyroidism. It was worth evey inconvenience and penny! He prescribes the typical T4 prescription, but he also prescribes a compounded timed-release small dose of natural thyroid extract, to result in an approx 98% T4 / 2% ratio (natural thyroid extract from porcine sources, like Armour, is about 80% T4/20% T3, which is not a human physiological ratio). He also makes small seasonal dose adjustments, as the reduction in natural winter sunlight makes many patients require a bit more hormone. He listened to me and treated me like an intelligent person, not a hysterical (now I know how that word came to be), middle aged hypochondriac.

    Every symptom has improved greatly and many symptoms have gone away. Some symptoms come have come back the last two autumns (he noted in my file that my calls about the some symptom increases were timed at nearly the same time in mid-September), so a slight dose increase takes care of them, then it is lowered again in the late spring. I also now make sure I get more outdoor light in the darker months (I live in So California, so that isn’t too hard, if I get outdoors enough).

    I wish I could go back and do things differently with the knowledge I have now, but of course that isn’t possible. I did manage to have one child, with the help of a fertility drug to boost ovulation. We had wanted a larger family, but it wasn’t to be despite additional fertility drug atttempts. Now I wonder if thyroid treatment would have been a simpler, better way to restore my fertility and to avoid the ovulation stimulation drugs. I also worry that my son’s IQ might have been affected by my low thyroid function during pregnancy. His IQ seems to be in a normal general range, but it doesn’t seem anywhere near the generally high level on either side of our families.

    Thanks very much for shining a needed light on this confusing and timely subject. While I don’t think that every weight problem is thyroid related (blood sugar and insulin abnormalities are also a big cause of weight gain), it is important to accurately assess the thyroid function treatment options, or at least make a decent attempt to rule it out (the full range of tests or a trial period on thyroid hormone). Even then, treating hypothyroidism isn’t a slam-dunk proposition. T4 supplementation alone is often not sufficient enough to resolve the many quality of life and health issues that hypothyroidism presents, yet it is the standard treatment protocol and patients are left stranded too often when some symptoms remain.

  9. Neil 4 April 2008 at 7:50 pm #

    Could I point to the work done by Ray Peat on TSH (and on many other subjects)


    He is, to my eyes, very concerned about the harmful effects of polyunsaturated oils

  10. Shay 5 April 2008 at 5:32 am #

    Harriet says:

    Hi, I found this fascinating as I am having my thyroid levels checked every six months because I have high antibody levels. However, despite having all the symptoms of hypothyroidism my results have remained normal apart from antibody levels going up hugely every time. I’m finding it all a bit depressing!!


    My aunt had all the symptoms of hypothyroidism for 20 years with normal thyroid tests. *Finally* they came back problematic and she was given her medication. It nearly drove her insane until she finally got help.

    My mother and I have similar problems. We (as a family of sicko’s!) have formed a hypothesis. We think that, in many cases, the thyroid “dies” gradually. It spends many years weakening and working in “fits and starts” until it finally can’t function at all any more.

    Until it weakens a great deal, the lab tests can’t detect the problem. (And it may be working just fine much of the time, with periods of time where it struggles.)

    This is just the theory of one frustrated family. The important thing is that you know that you’re not alone in this impossible situation. Keep plugging away and know that you will eventually win this fight!


  11. Sue 5 April 2008 at 10:10 am #

    Another book to read is called Tears behind closed doors by Diana Holmes who suffered for over 20 years with hypo as her tsh was fine.
    We need to educate our gp’s and Endocrinologists that they should listen to the patient as we are suffering with dreadful symptoms and not to just look at the tsh blood test result. This is for the diagnosis and management of hypothyroidism.
    Also levothyroxine does not suit everyone, we would like to have the choice of natural thyroid but most GP’s are too afraid to prescribe it.
    The worst thing is – GP’s and Endocrinologists tell us hypo patients that we need to lose weight!! and yet they want to lower our dose of medication, rather than increase it!!

  12. Chocolate Bunny 5 April 2008 at 2:09 pm #

    I had symptoms in my teens, and this go so much worse after giving birth, my first child is very intelligent, the second had problems at school.
    Every symptom I reported, and I now know I have adrenal problems as well as hypothryroidism, were dismissed by my doctor or treated as something else. I battled with my weight for years.

    I got so ill despite being treated on a very low dose (50mcg) of T4 for the past 7 or 8 years, although I have been ill for at least 30 years. My GPs wouldn’t change the dose as I was in the normal range, I saw an Endo who treated me for mild depression which made me much more depressed.

    When I got signed off by the Endo I felt so ill I had trouble getting up in the mornings to go to work, my husband had to sit me up on the side of the bed or I couldn’t wake. My weight had ballooned to an all time high, I had trouble walking due to painful joints, terrible concentration and memory and my balance was awful, and was being offered water tablets, blood pressure tablets – not the answer and I felt I would be either dead or disabled if I didn’t do something. I went to see Dr Peatfield last August, and I am now on Armour and adrenal supplements and feeling much better although there is a long way to go. I can do a working day without sleeping through it, I can get up and go on my own, I have lost 10 kilos so far, my blood pressure is now fine, the water retention is nearly gone, I have far less joint pain.

    I am paying for all of this, and my doctors aren’t too happy with what I am taking it seems. Just had a blood test which will be interesting but will only show TSH I am sure!

    The more doctors who think like you do Dr Briffa the better, maybe the world will change for the better!

  13. Richard Carruthers 5 April 2008 at 9:41 pm #


    The Effects Of Fluoride On
    The Thyroid Gland
    By Dr Barry Durrant-Peatfield MBBS LRCP MRCS
    Medical Advisor to Thyroid UK

    There is a daunting amount of research studies showing that the widely acclaimed benefits on fluoride dental health are more imagined than real. My main concern however, is the effect of sustained fluoride intake on general health. Again, there is a huge body of research literature on this subject, freely available and in the public domain.
    But this body of work was not considered by the York Review when their remit was changed from “Studies of the effects of fluoride on health” to “Studies on the effects of fluoridated water on health.” It is clearly evident that it was not considered by the BMA (Britsh Medical Association), British Dental Association (BDA), BFS (British Fluoridation Society) and FPHM, (Faculty for Public Health and Medicine) since they all insist, as in the briefing paper to Members of Parliament – that fluoridation is safe and non-injurious to health.
    This is a public disgrace, I will now show by reviewing the damaging effects of fluoridation, with special reference to thyroid illness.
    It has been known since the latter part of the 19th century that certain communities, notably in Argentina, India and Turkey were chronically ill, with premature ageing, arthritis, mental retardation, and infertility; and high levels of natural fluorides in the water were responsible. Not only was it clear that the fluoride was having a general effect on the health of the community, but in the early 1920s Goldemberg, working in Argentina showed that fluoride was displacing iodine; thus compounding the damage and rendering the community also hypothyroid from iodine deficiency.
    Highly damaging to the thyroid gland
    This was the basis of the research in the 1930s of May, Litzka, Gorlitzer von Mundy, who used fluoride preparations to treat over-active thyroid illness. Their patients either drank fluoridated water, swallowed fluoride pills or were bathed in fluoridated bath water; and their thyroid function was as a result, greatly depressed. The use in 1937 of fluorotyrosine for this purpose showed how effective this treatment was; but the effectiveness was difficult to predict and many patients suffered total thyroid loss. So it was given a new role and received a new name, Pardinon. It was marketed not for over-active thyroid disease but as a pesticide. (Note the manufacturer of fluorotyrosine was IG Farben who also made sarin, a gas used in World War II).

    This bit of history illustrates the fact that fluorides are dangerous in general and in particular highly damaging to the thyroid gland, a matter to which I shall return shortly. While it is unlikely that it will be disputed that fluorides are toxic – let us be reminded that they are Schedule 2 Poisons under the Poisons Act 1972, the matter in dispute is the level of toxicity attributable to given amounts; in today’s context the degree of damage caused by given concentrations in the water supply. While admitting its toxicity, proponents rely on the fact that it is diluted and therefore, it is claimed, unlikely to have deleterious effects.
    They could not be more mistaken
    It seems to me that we must be aware of how fluoride does its damage. It is an enzyme poison. Enzymes are complex protein compounds that vastly speed up biological chemical reactions while themselves remaining unchanged. As we speak, there occurs in all of us a vast multitude of these reactions to maintain life and

    produce the energy to sustain it. The chains of amino acids that make up these complex proteins are linked by simple compounds called amides; and it is with these that fluorine molecules react, splitting and distorting them, thus damaging the enzymes and their activity. Let it be said at once, this effect can occur at extraordinary low concentrations; even lower than the one part per million which is the dilution proposed for fluoridation in our water supply.
    The body can only eliminate half
    Moreover, fluorides are cumulative and build up steadily with ingestion of fluoride from all sources, which include not just water but the air we breathe and the food we eat. The use of fluoride toothpaste in dental hygiene and the coating of teeth are further sources of substantial levels of fluoride intake. The body can only eliminate half of the total intake, which means that the older you are the more fluoride will have accumulated in your body. Inevitably this means the ageing population is particularly targeted. And even worse for the very young there is a major element of risk in baby formula made with fluoridated water. The extreme sensitivity of the very young to fluoride toxicity makes this unacceptable. Since there are so many sources of fluoride in our everyday living, it will prove impossible to maintain an average level of 1ppm as is suggested.
    What is the result of these toxic effects?
    First the immune system. The distortion of protein structure causes the immune proteins to fail to recognise body proteins, and so instigate an attack on them, which is Autoimmune Disease. Autoimmune diseases constitute a body of disease processes troubling many thousands of people: Rheumatoid Arthritis, Systemic Lupus Erythematosis, Asthma and Systemic Sclerosis are examples; but in my particular context today, thyroid antibodies will be produced which will cause Thyroiditis resulting in the common hypothyroid disease, Hashimoto’s Disease and the hyperthyroidism of Graves’ Disease.
    Musculo Skeletal damage results further from the enzyme toxic effect; the collagen tissue of which muscles, tendons, ligaments and bones are made, is damaged. Rheumatoid illness, osteoporosis and deformation of bones inevitably follow. This toxic effect extends to the ameloblasts making tooth enamel, which is consequently weakened and then made brittle; and its visible appearance is, of course, dental fluorosis.
    The enzyme poison effect extends to our genes; DNA cannot repair itself, and chromosomes are damaged. Work at the University of Missouri showed genital damage, targeting ovaries and testes. Also affected is inter uterine growth and development of the foetus, especially the nervous system. Increased incidence of Down’s Syndrome has been documented.
    Fluorides are mutagenic. That is, they can cause the uncontrolled proliferation of cells we call cancer. This applies to cancer anywhere in the body; but bones are particularly picked out. The incidence of osteosarcoma in a study reporting in 1991 showed an unbelievable 50% increase. A report in 1955 in the New England Journal of Medicine showed a 400% increase in cancer of the thyroid in San Francisco during the period their water was fluoridated.
    My particular concern is the effect of fluorides on the thyroid gland
    Perhaps I may remind you about thyroid disease. The thyroid gland produces hormones which control our metabolism – the rate at which we burn our fuel. Deficiency is relatively common, much more than is generally accepted by many medical authorities: a figure of 1:4 or 1:3 by mid life is more likely. The illness is insidious in its onset and progression. People become tired, cold, overweight, depressed, constipated; they suffer arthritis, hair loss, infertility, atherosclerosis and chronic illness. Sadly, it is poorly diagnosed and poorly managed by very many doctors in this country.
    What concerns me so deeply is that in concentrations as low as 1ppm, fluorides damage the thyroid system on 4 levels.
    1. The enzyme manufacture of thyroid hormones within the thyroid gland itself. The process by which iodine is attached to the amino acid tyrosine and converted to the two significant thyroid hormones, thyroxine (T4) and liothyronine (T3), is slowed.

    2. The stimulation of certain G proteins from the toxic effect of fluoride (whose function is to govern uptake of substances into each of the cells of the body), has the effect of switching off the uptake into the cell of the active thyroid hormone.
    3. The thyroid control mechanism is compromised. The thyroid stimulating hormone output from the pituitary gland is inhibited by fluoride, thus reducing thyroid output of thyroid hormones.
    4. Fluoride competes for the receptor sites on the thyroid gland which respond to the thyroid stimulating hormone; so that less of this hormone reaches the thyroid gland and so less thyroid hormone is manufactured.
    These damaging effects, all of which occur with small concentrations of fluoride, have obvious and easily identifiable effects on thyroid status. The running down of thyroid hormone means a slow slide into hypothyroidism. Already the incidence of hypothyroidism is increasing as a result of other environmental toxins and pollutions together with wide spread nutritional deficiencies.
    141 million Europeans are at risk
    One further factor should give us deep anxiety. Professor Hume of Dundee, in his paper given earlier this year to the Novartis Foundation, pointed out that iodine deficiency is growing worldwide. There are 141 million Europeans are at risk; only 5 European countries are iodine sufficient. UK now falls into the marginal and focal category. Professor Hume recently produced figures to show that 40% of pregnant women in the Tayside region of Scotland were deficient by at least half of the iodine required for a normal pregnancy. A relatively high level of missing, decayed, filled teeth was noted in this non-fluoridated area, suggesting that the iodine deficiency was causing early hypothyroidism which interferes with the health of teeth. Dare one speculate on the result of now fluoridating the water?
    Displaces iodine in the body
    These figures would be worrying enough, since they mean that iodine deficiency, which results in hypothyroidism (thyroid hormone cannot be manufactured without iodine) is likely to affect huge numbers of people. What makes it infinitely worse, is that fluorine, being a halogen (chemically related to iodine), but very much more active, displaces iodine. So that the uptake of iodine is compromised by the ejection, as it were, of the iodine by fluorine. To condemn the entire population, already having marginal levels of iodine, to inevitable progressive failure of their thyroid system by fluoridating the water, borders on criminal lunacy.
    I would like to place a scenario in front of those colleagues who favour fluoridation. A new pill is marketed. Some trials not all together satisfactory, nevertheless, show a striking improvement in dental caries. Unfortunately, it has been found to be thyrotoxic, mutagenic, immunosuppressive, cause arthritis and infertility in comparatively small doses over a relatively short period of time.
    Do you think it should be marketed?
    Fluoridation of the nation’s water supply will do little for our dental health; but will have catastrophic effects on our general health. We cannot, must not, dare not, subject our nation to this appalling risk.
    Dr Barry Durrant-Peatfield obtained his Medical degrees in 1960 at Guy’s Hospital London. He left the NHS in 1980 to specialise in thyroid illnesses drawing inspiration from the work of infamous Dr Broda Barnes, at the Foundation that bears his name, Connecticut, USA. He has been a medical practitioner for over forty years specialising in metabolic disorders during which time he became a leading authority in the UK for thyroid and adrenal management. For over twenty years he also ran a successful private clinic and became a nation-wide leading authority on thyroid and adrenal dysfunction, but clashed with establishment medicine in the management of thyroid illness. He is the author of The Great Thyroid Scandal (see opposite page), he currently lectures at nutritional colleges in London as well as conducting his own teaching seminars. Barry will shortly be opening a diagnostic clinic in the UK for thyroid and adrenal disorders where he will provide advice on diagnosis and treatment with special interests in nutritional aspects. For further information contact: Dr B Durrant- Peatfield 36A High St, Mersham, Redhill Surrey, RH1 3EA.
    Tel: 44 (0)1737 215462 Email:
    Web site: http://www.drpeatfield.com

    L Goldemberg – La Semana Med 28:628 (1921) – cited in Wilson RH, DeEds F
    • “The Synergistic Action Of Thyroid On Fluoride Toxicity” Endocrinology 26:851 (1940).

    G Litzka – “Die experimentellen Grundlagen der Behandlung des Morbus Basedow und der Hyperthyreose mittels Fluortyrosin” Med Wochenschr 63:1037-1040 (1937) (discusses the basis of the use of fluorides in anti-thyroid medication, documents activity on liver, inhibition of glycolysis, etc.).
    W May – “Behandlung der Hypothyreosen einschlieblich des schweren genuinen Morbus Basedow mit Fluor” Klin Wochenschr 16: 562 – 564 (1937).
    Sarin: (GB: isopropyl methylphosono-fluoridate) is a colorless, odorless volatile liquid, soluble in water, first synthesized at IG Farben in 1938. It kills mainly through inhalation.
    Cyclosarin (GF) and Thiosarin are variants. Pennsylvania Department of Health
    Sarin: (GB: CH3-P(=O)(-F)(-OCH(CH3)2)
    Source: A FOA Briefing Book on Chemical Weapons
    http://www.opcw.org/resp/html/nerve.html Gerhard Schrader, a chemist at IG Farben, was given the task of developing a pesticide. Two years later a phosphorus compound with extremely high toxicity was produced for the first time.
    IG Farben: “…the board of American IG Farben had three directors from the Federal Reserve Bank of New York, the most influential of the various Federal Reserve Banks. American IG Farben. also had interlocks with Standard Oil of New Jersey, Ford Motor Company, Bank of Manhattan (later to become the Chase Manhattan Bank), and AEG. (German General Electric) Source: Moody’s Manual of Investments; 1930, page 2149.”
    At a later date, Namaste will be publishing a more in-depth article outlining the devastating affects that fluoride, aspartame and MSG have on the endocrine system.
    Dr Durrant-Peatfield will be answering frequently asked questions on thyroid
    illness in Namaste’s next issue. Send your questions to us preferably by
    email to: info@namastepublishing.co.uk

    [DOEWatch] List is for news and learning about energy issues related to DOE, energy, and industry. Fluoride and metal synergism’s are top issues for energy production and health. Subscribe via email, send Email to: DOEWatch-subscribe@topica.com or via the
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  14. jo knight 5 April 2008 at 11:35 pm #

    I have been taking thyroxine for 20+ years, and my gp adjusts the dose according to the ‘normal’ range – whereas I think how the patient feels is a consideration. I am now on 100mcg instead of 150mcg (which suited me better), and the feeling cold etc. symptoms have returned.

    I also have autoimmune disease, and a raised IgG immunoglobulin, anti-DNA, smooth muscle antibodies, and anti-nuclear antibodies, and I think my thyroid problems are all related to these problems. If only I could find a gp to see me as a whole person and treat accordingly, and put down the wretched ‘normal’ figures for thyroid diseases.

  15. Tina Michelucci 6 April 2008 at 12:19 am #

    I have an underactive thyroid and agree with Dr Briffa nd previous posts. I am also co-founder of http://www.dietfreedom.co.uk where we focus on eating a low GL diet. Our experience is that people who are hypothyroid find it difficult to metabolise carbs and a low GL / lower carb diet is the best option. With diet plus 50 mcg of thyroxine for the last 7 years I have managed to get back to my normal size 10 and stay there. I also have lots of energy now and am very active. In our experience a low body temperature is a good indication that your thyroid is not functioning properly and should be the first thing you do if you suspect you have a problem. Dr Andrew Wright in Bolton is a specialist in both thryoid and CFS and is excellent at diagnosing difficult cases. It is an area that desperately needs more funding and research but as it is not considered life threatening it seems to be way down the priority list despite causing so much distress and misery for so many. I also feel that it is linked to depression as untreated you feel very low indeed and do not have enough energy to exercise or take an active interest in life in general. After researching the subject when I originally suffered my GP said I knew more about it than he did! He also admitted that as their is a dire shortage of endocrinologists in the UK they cannot refer people even if they wanted to!

  16. jason 6 April 2008 at 6:09 pm #


    I have been underactive for the past 10 years and proberly in my teens , when i had my blood test in 1998 my TSH was 58.7.

    I am now on 200mgs of thyroxine and my last bloods My TSH was 0.03 i still get symptons and the worst is when i work it drain of energery that bad i have to take time off ,its a nightmere.

    One question i would like to know is why i never put weight on even before i was diagnosed i thought that was a classic sympton of hypo and recently i have lost weight .


  17. helen 7 April 2008 at 1:27 am #

    Soy is the biggest enemy of the thyroid there is – Theodore Kay of the Kyoto University Faculty of Medicine noted in 1988 that ‘thyroid enlargement in rats and humans, especially children and women, fed with soybeans has been known for half a century’.
    thyroid problems associated with soy were also well known to bird-breeders, Well known, but that fact seemed to escape manufacturers of the first commercially available soy formulas. Those formulas were known to cause in goitre in infants and one can only wonder how many other infants were left hypothyroid or suffering from permanent thyroid damage by soy formulas – For more info on soy and the thyroid check out this sity soy is not the great protein alternative to meat that the advertisers & meat haters think it is, it is a very dangerous toxic product.

  18. sophie 29 April 2008 at 8:11 pm #

    This is all so interesting but the subject is such a mind field that I just don’t know what to do.

    For the last 10 years every GP I have seen has commented on the size of my neck and wanted to investigate the goitre at the base. They’ve only done the normal blood tests and one utlra sound and always come up with the ‘oh its just one of those things, nothing is wrong’ conclusions. But recently I have become really tired even though I fall asleep within 5 minutes of my head hitting the pillow, and I sleep for 9 hours sold every night. I’ve also developed excma (dry skin) on my calfs which I find slightly strange. My weight is a slight issue, I’m a little larger than I feel I should be based on the amount of excercise that I do and my general fitness, but I’m not obese.

    But this whole thyroid thing is weighing on my mind. I recently registered with a new GP due to moving house, and he again wanted to do tests and of course they came back ‘normal’. I now don’t know whether just to leave it or ask for more tests – but I don’t know what tests! – they did a liver function and T3 and T4 tests. Any advice greatly appreciated.

  19. tracey johnson 16 May 2008 at 9:09 pm #

    Ive suffered underative for 8yrs and ive had bad deppresion and have put on 9stone in weight and have no enagy at all my memorys so bad and i dont feel 37 at all,ive been to doctors with bad constepation and had weeks of being unable to go to toilat the doctors have not a clue thay told me iam not drinking lots of water if i did id proubably drown,now i take flaxseed works a treat,doctors have given me no advice at all.

  20. sally brown 23 August 2008 at 9:01 pm #

    I’ve been taking thyroid since I was 14, when I developed Hashimoto’s and had a thyroidectomy. Last year my dentist recommended applying a prescription-strength fluoride gel daily to strengthen my teeth. I now think that’s the cause of my 12-lb. weight gain in 9 months (!!!), despite exercise and a good diet. I’m usually not someone who gains weight so dramatically.

    After reading that fluoride is a thyroid suppresent, no more fluoride gel or toothpaste for me!

  21. Vicky Bayliss 23 February 2009 at 8:29 pm #

    I have been having my thyroid levels checked for the past year first they were 9.2 now they have gone down to 2.2
    what causes this

  22. Nessy S 2 April 2009 at 10:54 pm #

    I find all this really fascinating. I have been hypo since birth and thankfully as the last of three children my mother realised something wasn’t right – there wasn’t any screening as I was born in Peru as my family were moved there for I believe the last 6 months of my mum’s pregnancy. She believes we’ve all been blessed with good, strong teeth because of higher flouride levels out there but I’m wondering now if this is the reason for my thyroid problem?

    I’ve been on thyroxine therefore since I was about 3 months old and more or less it has been stable. It was put up to 200mcg when I was on the Pill and when I was pregnant but generally has been 150mcg or 175mcg – the latter seems to be the ideal. About 15 months ago I came off the Pill again and the GP reduced my dose to 175mcg again. I feel I’ve been having weight problems ever since, I put on about 3/4 of a stone but I was going through a period of drinking more wine than I perhaps should have and in the past alcohol seems to have been the only thing that has made me put on weight. So towards the end of last summer I stopped drinking for 2 weeks and was reasonably careful about what I ate and I lost half a stone in about 3 weeks.

    The weight crept up again slowly and in February I decided to try and watch my diet again and do as I did before but my weight is completely static. This is very unusual, I have been told growing up that I would never have a problem with putting weight on and have been the envy of many friends watching me scoff biscuits and cakes and not put on a pound! Maybe it’s the past catching up with me!

    I started reading up on hypothyroidism as I had my last lot of blood tests around Sept/Oct last year and there were “fine” so I didn’t think it could be that however stumbled across all this research that blood tests are by no means conclusive and patients should be treated more individually. I talked to my GP who was good to a point and ordered a blood test but said it was probably my metabolism slowing down naturally (I’m 34) and I probably needed to exercise more (only exercise I get is looking after my 4 year old son).

    Surprise surprise the test has come back normal for TSH and the GP said if that was the case the lab won’t even look at the T4. I only spoke to a receptionist today when I got the results and she said, when asked, that the TSH level was 246 – doesn’t make much sense – seems a very high figure so not sure she was looking at the right one? Could it be 24.6, would that make more sense possibly, or 2.46?? Trying to find somewhere on the Internet that gives the approximate ranges for these tests but no luck so far, nothing that corresponds to such a large figure anyway.

    So still none the wiser, as we can’t afford to see anyone privately I guess I’ll have to just go with my blood test results and keep trying to lose the weight by upping my exercise but I am very interested and might monitor my temperature in the mornings.

  23. Shannon 11 April 2009 at 8:37 pm #

    First off I want to explain that I have a 15 month old daughter that still nurses about 2-3 times a day, I’m not sure if this has anything to do with it or not. I recenlty went to the dr to have my thyroid checked and all she ordered was the tsh and that came back normal, it was 25. My cholesterol is high also. At my appt my temp was 96.4, which is even low for me because it is usually 97.4. However, I do have low body temp. BP is low as well. I explained that I gained 9 lbs in less than 2 months. Before the weight gain I started exercising hoping it would give me more energy but it did the opposite and made me more tired. I have very bad memory and a hard time concentrating ( I am taking college classes online and am struggling!) I have absolutely no interest in sex and even though I can get 9 hours of sleep I wake up and feel like I was ran over by a mac truck. Also when I get up in the morning I feel “swollen”, especially in my hands and my face, I feel puffy. I don’t eat salty foods because of the fact that I retain water very easily. My doc was insistent that I am depressed (well who wouldn’t be when all this is happening and don’t understand why and don’t know what to do?) all she wanted to do was shove anti-depressenants down my throat! I just don’t know what to do next. I just hate feeling so run down all the time and not fitting into my clothes!

  24. Shannon 12 April 2009 at 2:21 am #

    I made a mistake on my previous post…my testosterone was 25 and my TSH was 1.51

  25. meThyroid 21 October 2011 at 4:03 pm #

    A lot of people focus on underactive thyroid but dont look into the cases where someone has gone from hyper to hypo due to thyroid treatment. Immediate change in body brings a lot of issues and stress which I am still find hard to cope with 🙁

  26. Soumya Bose 16 December 2013 at 7:17 am #


    I have a very confusing problem. I have a TSH level of 12.9 and blood sugar (fasting) of 124. Howver, no trace of sugar was found in the urine. This is the highest ever recorded as I was unable to control or exercise much in the past month. and also stopped my daily thyroid medicne (12.5 mg). Usually, I don’t take sweets, potatoes etc. exercise daily, don’t smoke or drink. The confusion is my symptomps don’t go with my results. I am not very fatigued or overactive, I am not gaining wiegth but lost a few, i am prone to cold, my pulse rate is not low, in fact, i have a problem of SVT, i feel urge of urniating frequently but not not very much, but my thirst is very less…. it’s all very mixed and confusing… please help


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