The actual term ‘Blue Monday’ is very recent and yes it’s nothing more than a creation of marketing in an effort mostly to boost holiday bookings.
Nothing wrong with that as such, and a lot of people in the Northern Hemisphere do indeed book their summer holidays in January, but there’s a hidden and less ‘famous’ far more concerning characteristic of winter for much of the population of the northern hemisphere living north of about 40 degrees north and that’s vitamin D deficiency.
As a species in even recent times we would spend much of our time outdoors when sun angles were above 45 degrees from the horizon (typically April-September), but with the rapid rise of the office environment, cars with UVB filters in their glass and people living further north than they would naturally much of the population are either low or deficient in vitamin D.
As you can see from the image, vitamin D3 is synthesised through the skin and also metabolised in the liver. The primary source is from sunlight. Vitamin D is actually a hormone, but the name ‘vitamin’ is used because a classified disease, rickets is attributed to very low levels of vitamin D. Yes, it can be obtained from food but it tends to be most concentrated in organs such as liver which many no longer eat as food. The absolute best source is sunlight.
The concern which has been shown by many health authorities is that populations are low, or deficient in vitamin d3 (25-hydroxycholecalciferol) and this causes health problems beyond the scope of the common thought process of rickets.
These concerns are wide-ranging to the point that the Scientific Advisory Commission on Nutrition released new guidelines for Public Health England advising supplementation of 10micrograms (400iu) per day for EVERYONE over the age of one year.
The official press notice is published here
The full report is available here and point 6.242 describes a finding on all cause mortality and Vitamin D. The report mentions many diseases far beyond skeletal concerns including many cancers and cardiovascular concerns such as high blood pressure.
In particular, it is noteworthy that a U shaped relationship exists so exceeding the recommended supplementation isn’t advised unless prescribed by a GP and only then after a deficiency being shown on blood analysis.
Blue Monday may well be a product of marketing but for those living at higher latitudes, the best and most effective method to increasing serum Vitamin D levels is indeed heading to more southern latitudes and so perhaps it’s not such a bad thing after all.
If you are concerned about your Vitamin D levels then it’s sensible to speak to your GP or message us for a finger prick blood kit which can tell you objectively your levels.