As the evenings start getting darker again, the lack of daylight can leave people feeling tired and more sluggish than normal. However, in some cases, constant fatigue can be a sign of something more significant than the changing of the seasons.
Here we explore six of these health issues...
Essentially an iron-deficiency which can reduce the amount of oxygen supplied to tissues and organs, anaemia is easily detected via a blood test.
The NHS advises that symptoms of iron-deficiency anaemia can include tiredness and a lack of energy, shortness of breath, heart palpitations and pale skin.
It can affect both men and women and is commonly found in women, particularly during pregnancy or heavy periods.
Treatment involves adding extra iron to the diet, often via a course of high strength prescription supplements, to replace that which is missing and bring your levels back in line.
The type of hairloss this condition can cause is known as Telogen Effluvium; it involves shedding from all over the scalp, with diffuse hair fall affecting around 30 per cent of the head at once. Typically hair regrowth will resume naturally once the underlying cause has been dealt with - in this case, the iron deficiency.
It can last up to six months, though Telogen Effluvium treatment may help to accelerate this process. Should the affected individual also have active genetic hair loss, or the relevant dormant predisposition to Male Pattern Baldness or Female Pattern Hair Loss, these can be exacerbated or prematurely triggered.
Pernicious anaemia follows much the same pattern and advice as for iron-deficiency anaemia, however, instead of a lack of iron, it relates to a deficiency in vitamin B12 and/or vitamin B9 (folate).
Symptoms include extreme tiredness, pins and needles, a sore and red tongue, mouth ulcers, muscle weakness, disturbed vision, depression and confusion, and memory problems.
This is mostly seen in people who are unable to properly absorb these nutrients - such as those with autoimmune disorders including Alopecia Areata - and, therefore, may unknowingly require higher doses. It is also a potential concern for those with a poor diet and is mostly found in those aged 75 or over.
Again, the hair loss condition that can be triggered during pernicious anaemia is Telogen Effluvium.
Hypothyroidism, also known as an underactive thyroid, can lead to tiredness, weight gain, dry hair and skin, muscle aches, cold sensitivity and feelings of depression.
It is diagnosed via a thyroid function test; this involves having a blood test to measure hormone levels. Although it can affect both men and women it is more common in women and it is possible for children to be born with the condition.
Treatment involves taking levothyroxine, a hormone replacement tablet taken daily to increase thyroxine levels. Hair loss, again in the form of Telogen Effluvium or Chronic Telogen Effluvium, also known as Diffuse Thinning, is a known side effect of this medication.
Hyperthyroidism is where the thyroid is overactive; this can cause nervousness and anxiety, irritability, mood swings, difficulty sleeping, persistent tiredness, swelling in the neck, heart palpitations, itchiness, a sensitivity to heat, thinning hair and weight loss.
According to the NHS, an overactive thyroid is ten times more likely to affect women than men, and is often diagnosed when people are aged 20 to 40 years old.
In addition to hair thinning from Telogen Effluvium or Diffuse Thinning triggered by the underlying illness, treatment for hyperthyroidism may also cause temporary hair loss. An endocrinologist may recommend medication such as carbimazole, propylthouracil or beta blockers, all of which list thinning hair as a potential side effect.
Once the body has adjusted to the medication this shedding should stop and normal hair growth should resume, but if the hairloss persists for longer than a few weeks, professional advice should be sought.
Diabetes is a condition that can cause a person's blood sugar levels to become too high and, whether type 1 or type 2, it has known links to hair loss.
Type 1 diabetes is an autoimmune disorder and, therefore, as people with any existing autoimmune diseases are more prone to developing others, those people with hair loss from Alopecia Areata, Alopecia Totalis or Alopecia Universalis are more likely to develop this insulin-related condition. Conversely, those with type 1 diabetes have a higher chance of developing forms of Alopecia Areata.
The mildest form of Alopecia Areata involves patchy hair loss of the scalp only; this may be temporary - lasting up to 12 months at a time - or may come and go over the years. Alopecia Areata treatment can be helpful for this phenotype, however, for the more severe forms which cause baldness of the head, or from head to toe, a dermatologist's advice should be taken given treatments for these tend to be hospital-based.
Both type 1 and type 2 diabetes - the more common of the two - are also linked to Telogen Effluvium and Diffuse Thinning. This is because the underlying chronic illness places a strain on the body which then diverts its resources towards maintaining critical functions. This can leave non-vital functions temporarily under-resourced.
In the case of hair growth, this can result in diffuse hair loss until the body is over this stress - usually once the health condition is being properly managed. It is possible for people with diabetes to use hair loss treatment and anyone concerned about on-going shedding may wish to consult a dedicated specialist about their options.
Willis-Ekbom disease, more commonly known as restless legs syndrome, is a common issue related to the nervous system. As the name suggests, the main symptom is a constant urge to move the legs, often worsening at night.
It causes a 'crawling' sensation from the feet to the thighs and can also involve involuntary jerking of the limbs, including arms, with women being twice as likely to have restless legs syndrome than men.
Thought to be related to how the body processes the chemical dopamine, restless legs syndrome is also thought to have genetic qualities and may be hereditary. It can also present as an additional symptom to iron-deficiency anaemia, pregnancy and kidney failure.
In mild cases it may only present occasionally, whilst for those where it is more severe it may happen daily. When it is so frequent it can have negative consequences for a person's all-round well-being, largely due to the anxiety and lack of sleep - sometimes leading to insomnia - that it engenders.
This can lead to stress-related hair loss, most likely due to Chronic Telogen Effluvium, as well as dry, thinning hair given healthy hair growth requires good sleep hygiene. However, once the underlying reason for this condition developing has been diagnosed and dealt with, the hair should return to normal.
Frequent lack of sleep is essentially a form of stress, so needs to be properly managed.
Getting enough sleep on a regular basis is important for healthy hair growth, as well as for our overall well-being. Therefore, if you are feeling tired all the time and there's no immediately obvious cause - looking after small children, noisy neighbours or late-night Netflix binges, for example - it is certainly worthwhile speaking to your GP about your concerns.
The Belgravia Centre is a world-renowned group of a hair loss clinic in Central London, UK. If you are worried about hair loss you can arrange a free consultation with a hair loss expert or complete our Online Consultation from anywhere in the world for home-use treatment.
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