Unexplained fatigue

We all feel tired from time to time; a busy family and social life, a few late nights, deadlines at work – whatever the reason, tiredness can catch up with all of us at times.

But you may have realised that you’re feeling tired all the time, perhaps for no apparent reason, and even tired when you wake up. It’s a common problem. I see lots of clients who are, to some extent, ‘tired for no reason’. ONE of the reasons may be an underactive thyroid.

Production of too little thyroid hormone (hypothyroidism) is a common cause of unexplained fatigue; production can be affected by all sorts of things – an autoimmune response, for example, or other factors such as prolonged stress or intake of certain drugs which can damage your thyroid.

Thyroid function is assessed via blood tests but often few markers are included, and whether you are found to be inside or outside the normal range can depend on where the test is carried out.

In the UK, the healthy range for the most commonly used test – known as TSH (thyroid stimulating hormone) – is between 0.5 and 5, although many experts will refuse to treat a patient until the level reaches 10 (the job of TSH is to make the thyroid produce more, so when it is high it means the thyroid is underfunctioning). But four years ago, the American Association of Clinical Endocrinologists recommended that: “Doctors consider treatment for patients who test outside a TSH range of 0.3 to 3”. The Association commented that it would make 20% of the USA hypothyroid.

The Department of Health guidelines say that ‘blood tests are useful but should not be used in isolation’. In other words, you need to take symptoms into consideration as well. So the first thing to do if you are worried about your thyroid levels and have had them tested by the doctor, is not to ask for actual numbers and ask what the testing lab considers a normal range.

If possible, get a copy of the actual report. If it shows that your TSH level is above 2.4 to 3.0 and you are told that this is normal, point out that the American Association of Clinical Endocrinologist (AACE) now recommends treating when TSH goes above 3.0. A more detailed test can be run by private laboratories. You would need to see a qualified nutritional therapist to gain access to this. You would then be tested for Total Thyroid Screen which includes TSH, anti-thyroid antibodies, thyroxine (T4) and triiodothyronine (T3), as well as Reverse T3. T4 is converted into T3, the active thyroid hormone. For more details, contact Nourish. 

Sometimes you can have a normal T4 but a low T3, which means your ability to convert T4 into T3 is impaired and you feel tired as a result. If this is the case, follow our nutritional guidelines below. If your TSH is high, but your thyroid hormone (T4 and T3) levels are normal, one possibility is that you have too much oestrogen, which competes with thyroid hormones at hormone receptor sites. In other words, your body is able to make the thyroid hormones, but the message isn’t getting through.

Supporting your thyroid through nutrition
The two most common causes of an underactive thyroid are general endocrine underfunction, more on this below, or an auto-immune condition called Hashimoto’s Thyroiditis, where your body produces anti-bodies that attack the thyroid. This second factor can be identified by testing for what are called ‘anti-thyroid antibodies’. Autoimmune disease, including Hashimoto’s, has been linked extensively in research studies to consumption of gluten, due to the systemic inflammation that gluten promotes, and the very similar molecular structure of gluten and the thyroid gland. We recommend all clients suffering from autoimmunity avoid gluten strictly to reduce inflammation and tissue damage. Sometimes, giving up gluten is not enough and you may also react to the protein in dairy known as casein, which is similar enough to gluten to cause cross-reactivity in some cases.  If you are interested in food intolerance testing please contact Nourish for a free 15 minute chat.

Thyroid hormones are made from the amino acid tyrosine, which is converted into thyroxine (T4), then into T3, by enzymes that depend on zinc, selenium and iodine. B vitamins are also important. A good-quality multivitamin/mineral supplement can be helpful in delivering these nutrients, although be careful where you buy from as most supplements from supermarkets, chemists and high street shops contain less bio-available nutrients, as well as fillers and preservatives, and we therefore do not recommend them. Extra zinc (up to 20mg a day in total) or extra selenium (up to a maximum of 200mcg in total) is sometimes suggested. Please be careful with iodine supplementation though as research suggests that supplemental iodine, or high-iodine foods like seaweed, can raise thyroid antibody levels and therefore promote further tissue destruction in autoimmune thyroid disease.

Depending on the root cause of your thyroid under function, a thyroid supporting diet would include:

  • some good quality protein with each meal (meat, fish, eggs, nuts, seeds or tofu)
  • include foods containing iodine (seaweed) (but not in autoimmune thyroid conditions)
  • 50% plant based food for at least two meals per day
  • good quality fats (olive oil, coconut fat, butter, ghee, flaxseed oil)
  • Avoid sugar, boxed breakfast cereals, cakes, pastries, sweets, processed foods

You may also want to supplement 200mcg of chromium as this supports blood sugar balance, energy and low mood. If none of this works, we recommend exploring the possibility that you have an underactive thyroid that needs to be explored with laboratory testing and possible thyroid hormone replacement.

These are general guidelines – for more detailed advice, why not book in for a consultation. If you want to explore lab testing, consult your GP or talk to us about booking a private, comprehensive thyroid panel test.

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