How do I know whether my fatigue is caused by my thyroid?
Thyroid blood tests can rule out or confirm whether your thyroid is the cause, but a mildly abnormal TSH alone does not explain fatigue and treating it often does not help. In Hashimoto's, symptoms can persist even when your values are normal.
Fatigue is one of the best-known complaints associated with thyroid problems, but the connection is more complicated than it appears. A clearly underactive thyroid typically comes with other symptoms alongside fatigue, such as a slow heart rate, feeling cold all the time and constipation. That pattern is strong enough to point toward the thyroid and make blood testing worthwhile.
A blood test measures the TSH hormone, which is the control signal for your thyroid. A raised TSH combined with a normal free thyroid hormone (FT4) is called subclinical hypothyroidism. That sounds as though treating it would resolve the fatigue, but it does not. Across 21 randomised trials involving more than 2,000 participants, thyroid hormone treatment (levothyroxine) for subclinical hypothyroidism produced no measurable benefit for fatigue, quality of life or low mood. Treatment therefore makes little sense for this diagnosis when fatigue is the only complaint. An additional consideration: in older people TSH naturally rises with age, meaning subclinical hypothyroidism is sometimes over-diagnosed.
A separate category is the autoimmune condition Hashimoto's thyroiditis. People with Hashimoto's more frequently experience fatigue, forgetfulness, anxiety and sleep problems, even when their TSH and thyroid hormone levels are completely normal. Elevated antibodies (the immune proteins that attack the body's own thyroid tissue) are associated with greater inflammation in the body and a poorer quality of life. In that case the fatigue does not stem from a shortage of thyroid hormone, but appears to be driven by the immune process itself. This also means your TSH value can be normal while you still feel unwell.
Finally, there is subacute thyroiditis, which often follows a viral infection. It is accompanied by pain in the throat, fatigue and muscle aches. This condition typically resolves completely. If fatigue persists despite a normal or treated thyroid, it probably has a different cause. Think of sleep problems, anaemia, stress or another condition. Have your blood values checked by your GP if you are persistently tired, but do not automatically expect a thyroid diagnosis or supplement to be the solution.
Claims are based on a large meta-analysis (n=2192, 21 RCTs) for the treatment effect, and observational studies for the association between Hashimoto's/hypothyroidism and fatigue complaints. TSH as a diagnostic tool is broadly validated.
What are the symptoms of an underactive thyroid and when should you see a doctor?
An underactive thyroid produces vague complaints such as fatigue, weight gain and cold intolerance, but the diagnosis can only be made through a blood test. If you have recognised several complaints for a while, discuss them with your general practitioner.
How do I keep my kidneys healthy as I age?
The two best-supported steps to limit kidney damage as you age are keeping your blood pressure under control and exercising regularly. Moderate salt intake and a healthy weight demonstrably contribute to both.
Do your eyes age faster than the rest of your body?
The lens of the eye ages noticeably early and quickly, but whether your eyes as a whole age faster than the rest of your body has not been demonstrated. The retina actually reveals a great deal about your overall health, so the two track more closely together than you might think.
Do your kidneys age at a different rate than your liver?
The kidneys age measurably faster than the liver, but for most healthy people that decline only has major consequences when dosing medications at an advanced age. If you also have high blood pressure or diabetes, it is wise to have your kidney function checked regularly.
How do I keep my joints supple and prevent osteoarthritis?
Exercise and maintaining a healthy weight are the best-supported ways to prevent osteoarthritis and manage symptoms; however, no treatment stops the disease once it has begun.
How do you recognise gum recession early, and which habits can inadvertently make the problem worse?
Early gum recession is usually only detected by the dentist, not at home. Aggressive brushing, inflammation and smoking are the habits that offer the most concrete room for improvement.