Beat the winter blues

Beat the winter blues

14 January 2012

What is Vitamin D
Vitamin D is a fat-soluble steroid pre-hormone which has wide reaching effects on health as it is involved in > 1000 genes. Recent research highlights the fact that there is still no official recommendation for a minimum level and UK DoH guidelines are vague, as are UK health charities guidelines on sun exposure.
US recommended daily amount (RDA) is currently600iu.
As most people are aware vitamin D is made in the body by the action of sunlight on the skin and eyes. Small amounts are obtained through diet.

What does Vitamin D do?
Vitamin D acts on target cells in every organ in the body activating/deactivating transcription of genes regarding:-
• Calcium balance in the blood and bone
• Cell proliferation and differentiation
• Immunity especially immune tolerance.
• Prevents pathogens sticking to wall of gut
• Increases insulin secretion
• Affects BP regulation
• Neurotransmitter synthesis

Therefore the following conditions could be prevented or reduced:-
Osteoporosis, Rickets, Muscle weakness and falls, Cancer (19 types), SAD, Dementia and Alzheimer’s, Heart disease, Diabetes, Infectious immune disorders, Respiratory disease, Autoimmune disorders, Periodontal disease, Multiple Sclerosis, Chron’s disease, Psoriasis, Parkinson’s, meningitis, tuberculosis.

Vitamin D sources
There are three ways to up your blood level of vitamin D – eat it, supplement it or expose yourself to sunlight.
Eat it
three servings of oily fish a week (a serving of salmon or mackerel provides around 350iu)
six free-range eggs a week (an egg provides 20iu)
That equates to approx 200ius a day from your diet.
Vitamin D2: ergocalciferol only half as potent as Vitamin D3: cholecalciferol. Most studies are done on D3.
Multi vitamins will contain between 200iu (5mcg) – 600iu (15mcg)
Vitamin D is primarily sourced from sunlight directly on the skin/eyes

Several factors affect this uptake:
• Latitude and season, primarily in the UK is the lack of sun! Complete cloud cover reduces vitamin D synthesis by 50%.
• 45% English people have <40nmol/L (current UK ref range is 40 – 140 nmol/L) Normal being defined as don’t have Rickets!
• Skin melanin content, darker skins absorb less vitamin D
• The use of high factor sunscreen and makeup.
UVB rays do not penetrate glass – we now spend more time inside or in a car than our ancestors did.
• People with a regular high sun exposure can reach levels of 163noml/L

Recent Research on Vitamin D
Recent research highlights that a UK reference nutrient intake (RNI) needs to be set (this is equivalent to the US RDA). As well as a sensible safe upper level for supplementation, blood serum levels need to be adjusted (suggested to be 100-150nmo/L).

Leading vitamin D expert Dr William Grant has predicted that if average serum levels of Vitamin D were increased from 54 to 105nmol/L
• Heart disease would decrease by 40%
• Colorectal cancer incidence would decrease by 30%
• Risk of Breast cancer would decrease by 35%
• Life expectancy would INCREASE by 2 years
• Healthcare costs may decrease by 20%

Who is deficient?
Well probably everybody in the UK but particularly at risk are:
• People who have had Gastric banding
• Pregnant/breastfeeding mothers
• Breast fed Babies (due to low levels in mother)
• Children age 6 months – 5 years
• Over 65
• Housebound or covered up for long periods of time.
• Darker skinned
• Drug interactions: –
Steroids can impair Vitamin D metabolism and reduce Calcium absorption.
Oristat (weight loss drug) and Cholestyramine can lower vitamin D absorption.
Epilepsy drugs – some can increase conversion of vitamin D to inactive forms and therefore reduce calcium absorption.

Vitamin D co-factors
Several nutrients are required by the body in order for Vitamin D to be utilised efficiently:-
Magnesium is required for every enzyme in vitamin D metabolism and synthesis, and is necessary for it’s beneficial effect on bone and the immune system.
Zinc is required for vitamin D’s role in calcium balance and in the immune system.
Boron is required for enzymes that metabolise vitamin D.
Vitamin K2 is required for vitamin D’s role in bone health.

Calcium is often prescribed for bone health without looking at the status of other important co-factors. High levels of calcium can lead to calcification of tissues affecting arthritis and heart disease.

What should I do?
If you are concerned about your levels of Vitamin D, testing can be arranged. I have finger prick test kits available at £60

• In Winter get at least 15-20 minutes of daylight each day.
• In Summer – sunbathe for 20 minutes daily in the middle of the day without sunscreen (be careful if you have fair skin not to burn)
• Wear sunglasses when necessary but not all the time to allow direct sunlight on the eyes.
• Include oily fish (3 x week) and eggs (6 a week) in your diet regularly.
• Supplement with a good quality multi vitamin and mineral

After testing a Vitamin D3 supplement can be taken to boost levels
My test results
I decided to run the test myself out of interest and was surprised that despite following the diet recommendations, taking a multi vitamin & mineral supplement and trying to get as much sun as possible this year my levels were a pathetic 46.3nmol/L well below the suggested reference range. I am currently taking additional D3. It just goes to show that we do not get enough sun in this country and a holiday abroad isn’t enough to top up Vitamin D levels either.

Gillian Key MBANT Nutritional Therapist.