(Seasonal affective depression - SAD)
Winter tiredness due to lack of sunlight is known as seasonal affective depression (SAD) and the Winter blues.
It can be prevented by taking vitamin D supplements and by using a sun light. Supporting the immune system in this way may also increase resistance to Covid.
Taking vitamin D unsupported by vitamin K can cause calcification of the blood vessels and consequently increase the risk of ischaemic heart disease. Also, combining with vitamin K reduces the required dose of vitamin D.
Current government advice is that adults should take at least 24 mcg (1000 international units) of vitamin D3 a day.
A recommendable vitamin D preparation is K-Right, Jarrow (60 capsules), one capsule to be taken daily. This is the only vitamin D preparation that has been found at this clinic to test consistently effective .
It is available from iHerb - cost about £30 including postage.
Content of each K-Right softgel
Vitamin D3 (Cholecalciferol) 50 micrograms (2000 i.u.) Vitamin K1 (phylloquinone) 500 micrograms
Vitamin K2 (MK-4). 1500 micrograms
Vitamin K2 (as naturel MK-7). 180 micrograms
Do not self-medicate with vitamin K if you are pregnant, trying to conceive or taking anticoagulants such as warfarin and coumadin.
Research in Scandinavia has indicated that taking vitamin D supplements does not altogether prevent tiredness due to deprivation of sunlight in winter. In view of this, it is advisable to use a sunlight during winter in addition to taking vitamin D supplements.
A suitable sunlight is the LED Energy Lamp,
HappyLight Lucen, Model: VT22 is obtainable from www.verilux.com.
This model, which is made in China, has a US plug, so that a US-UK adaptor plug is needed, (e.g., Go, 315Z, Ref.554, BS 8546). In any event, the adaptor should have a flat insert face without an indent for a protruding US plug.
About ten minutes a day exposure to a sun light is normally sufficient.