Thyroid – Are you undiagnosed?

Have you really had your thyroid checked? It’s quite common to have your thyroid checked as part of the standard, routine tests, yet usually the only check made to assess thyroid status is the hormone known as Thyroid Stimulating Hormone (TSH): however, for many the TSH can be normal and therefore misleading! If you suspect that you have hypo or hyper thyroid symptoms, understanding and assessing the status of your thyroid function can be tricky, but you don’t have to let that stand in your way!

Medicare rebates only applies on TSH testing, so you will need to consider paying for other tests, including thyroid hormones T3 & T4, reverse T3, thyroid antibodies, cortisol and thyroid cofactors (see below for a better explanation of these).  An expert practitioner will be able to explain the correct reference ranges, correct ratios between thyroid hormones and understand the complexity involved in reading iodine results.

What does the thyroid do?

The thyroid hormones promote normal fetal and childhood growth, central nervous system development, regulate heart rate, heart contraction and relaxation, digestive motility, water clearance, control the body’s energy expenditure, heat generation, weight and lipid metabolism.

So quite a bit!

HYPOTHYROID SIGNS & SYMPTOMS – Low thyroid function

 So what type of signs and symptoms could make us suspect low thyroid issues, you might ask? 

• Depression
• fatigue & lethargy
• forgetfulness, decreased concentration, memory deficit, slow thinking
• cold intolerance and cold extremities
• decreases sweating
• headaches
• weakness, cramps, myalgia, arthralgia
• hypercholesterolaemia and diastolic hypertension
• iron deficiency
• shortness of breath
• constipation, flactulence, bloating
• puffy eyes, goitre, dysphagia, sore throat
• lowered immune response
• recurrent infections
• impaired kidney function
• low libido, infertility, menstrual irregularities, fibrocystic breast disease, menorrhagia
• hyperprolactinaemia
• impotence
• dry skin, coarse skin, brittle and coarse hair and nails, hair loss
• weight gain, difficulty losing weight and oedema

HYPERTHYROID SIGNS & SYMPTOMS – High thyroid function

What about hyperthyroid signs and symptoms!

• Fatigue, weakness,
• warm and moist skin, sweating
• fine hair
• tremors
• back pain
• loss of stamina
• palpitations, chest pain
• oedema, dyspnoea
• increased bowel motility
• gritty sensation in the eye, photphobia, eye pain, protruding eye, visual loss
• polyruia, polydipsia
• easy bruising
• heat intolerance
• weight loss despite increased appetite
• irregular menstrual periods, impotence
• restlessness, anxiety, irritability
• insomnia

TSH – What is it and where should it be?

TSH is the hormone released in the brain in response to low levels of thyroid hormones T3 & T4: its job is to stimulate the thyroid to release more thyroid hormones, so TSH levels elevate when thyroid hormones are low and decrease as thyroid hormones rise. Unfortunately, the upper level for most labs is too high (usually 4.12mIU/L). Even though the National Academy of Clinical Biochemistry in 2005 recommended the upper limit of TSH to be lowered to 2.5mIU/L, this news hasn’t it made it into orthodox medical practice, resulting in many people being told that their thyroid looks fine when in fact it may be > 4 mlU/L. Obviously this in turn creates a situation where further investigations are made later rather than sooner.

THYROID CHECKLIST

Lets take a quick look at the ideal, thorough checklist of the thyroid:

TSH

Thyroid stimulating hormone is released by the pituitary gland in the brain and stimulates the thyroid gland to release thyroid hormones, primarily T4 and T3. It makes sense to check that the thyroid is being sent its message to produce hormones.

Thyroid hormones

Thyroxine (T4) is the main thyroid hormone released and converts to the active form triiodothyronine (T3). Inadequate amounts of T4 are suggestive of iodine deficiency. The ratio between T4 and T3 provides clues as to what the thyroid is doing. 

Thyroid autoantibodies

Thyroperoxidase antibodies (TPOAb), thyroglobulin antibodies (TGAb), thyroid stimulating thyroid receptor antibodies (TRAb) are antibodies that when elevated suggest thyroid autoimmunity (the immune system attacking the thyroid), indicating possible inflammation of the thyroid. Levels are normally elevated in diseases of the thyroid such as Hashimoto’s thyroiditis, thyroid carcinoma and Grave’s disease. TSH receptor auto-antibodies generally stimulate the TSH receptor causing Grave’s disease.

Reverse T3 (rT3)

Is an inactive form of T3 that is produced in the body particularly during periods of stress, this protects metabolism becoming too unstable during times of stress. When elevated can suggest that stress (physical or emotional by the way) is effecting the thyroid.

Cortisol

Cortisol is our stress hormone and effects thyroid function and therefore can be useful in assessing if the cause is coming from the adrenal glands (which release cortisol).

Minerals

Iodine makes up the structure of the thyroid hormones correctly assessing iodine status is important there are urinary spot and urinary loading tests, the loading test may be more accurate but may not be advisable in certain situations (those taking pharmaceutical thyroid drugs such as thyroxine cannot do the loading test) and therefore a spot test can be used but must always be completed with a urinary creatinine test to ensure accurate interpretation. Selenium is responsible for converting T4 to T3, making it supper important if we want enough T3 available to our cells. Zinc effects both TSH and thyroid hormone levels. Iron deficiency effects thyroid hormones from being made.

*Note the hair loss attributed to hypothyroidism may not improve without zinc supplementation, even if thyroxine – pharmaceutical drug, is given.

Special Note – IODINE DEFICIENCY IS RE-EMERGING IN AUSTRALIA

We need to pay close attention to this, as iodine is critical to humans and especially growing children. But before you just go off and start supplementing with large doses of iodine, my recommendation would be that you ensure you know exactly what is happening with all of the above levels (please note I am suggesting caution with HIGH doses).  Starting with low doses and building up is a sensible approach, the thyroid hates being shocked!

*kelp granules are a great source of iodine and can be sprinkled into food like you would salt and pepper – this will not be an adequate dose for those with severe deficiencies, but great for those who want to include iodine in their diet.

Finally it is extremely important that women who are planing to fall pregnant have their TSH levels and iodine levels checked as thyroid hormones are critical for pregnancy. 

REFERENCES

• NCBI- Zink & Hypothyroidism
• Inositol & selenium reduces antibodies
• Hormones-serum zinc levels, thyroid hormones
• Bio med-TSH and thyroid hormones
• JCEM-Normal TSH Reference Range
• Wiley-iodine deficiency
• Wiley-Iodine Intakes