Dr Downing is the current president of the British Society for Ecological Medicine, editor of the Journal of Nutritional and Environmental Medicine and medical director of the Alliance for Natural Health. He practices ecological medicine with the New Medicine Group.

The holidays are over, the nights are drawing in. The clocks just went back; now is when SAD sufferers really start to feel it. By Christmas we’ll all be feeling it to some extent, and some of us will be getting flu or other seasonal ailments. But there is one simple measure you can take to help prevent all of this.

Winter Blues.
Vitamin D is better for SAD than bright light therapy. A one-off megadose of vitamin D (100,000 units, equivalent to 20 of the 5000iu capsules) works better on seasonal depression (SAD) than a week of bright light therapy. A daily dose of 800 units doesn’t do anything for SAD, but nobody has yet studied what 4,000 or 5,000 units every day would do. 4000iu certainly does improve depression in general, in only 3 months, while 600 units only works in summer — when you’re also getting vitamin D from sunlight [2].

Flu?
You guessed it - vitamin D. There’s better evidence that vitamin D will reduce your risk of flu and its complications than there is for vaccination. Unless you’ve got a bolt-hole in Spain or somewhere hot, you’ll need to take vitamin D supplements through the winter to stay replete. In fact I would advise keeping on taking them; the results of taking 2000iu per day (97% reduction in colds and influenza) don’t show after 12 weeks, only after months [1].

Falls
A new review in the BMJ [3] shows that 700 to 1000iu of vitamin D a day reduces falls in older people by 19%, while 200 to 600iu doesn’t. Sadly, none of the studies collected in this paper looked at what many scientists would consider a sensible dose of vitamin D – around 4000 to 5000iu. It’s a good bet that the results would be even better.

Other diseases.
The Vitamin D Council website says:
We propose Vitamin D Deficiency Syndrome exists when 25(OH) vitamin D levels of less than 25!ng/mL are
found in patients with two or more of the following conditions: osteoporosis, heart disease, hypertension,
autoimmune diseases, certain cancers, depression, chronic fatigue, or chronic pain. VDDS is more common
among dark skinned races, the aged, and those who avoid the sun.

That’s most diseases, really – and 87% of us in the UK have a blood level less than 75 nmol/L, which is 30 ng/ml, so we’re nearly all deficient by this standard. So one vitamin D capsule daily right through the
winter is what I’ll carry on taking.

Dose is everything.
I know these numbers are confusing, but it’s quite simple really; the RDAs (Recommended Daily Allowances) for vitamin D are far too low, and hopelessly outdated. 600iu per day doesn’t do much; 2000iu is better, but 4000iu is around what we all really need.

Vitamin D really is the “gorilla in the room”. And please don’t worry about toxicity; if you took 40,000 units every day for weeks you might start to get symptoms, below that you won’t. Just remember that vitamin D3, cholecalciferol, is the right stuff for humans; vitamin D2, ergocalciferol, is less effective and more toxic. It’s a yeast hormone, not a human one. Read the label.

References
1. John J Cannell, Michael Zasloff et al. On the epidemiology of influenza. Virology Journal 2008, 5:29
2. Vieth R, Kimball S et al. Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients. Nutrition Journal 2004, 3:8 doi: 10.1186/1475-2891-3-8
3. Bischoff-Ferrari HA, Dawson-Hughes B et al. Fall prevention with supplemental and active forms of vitamin D: a metaanalysis of randomise controlled trials. BMJ2009; 339:b3692 doi: 10.1136/bmj.b3692

Product Insight – Vitamin D
There are many reasons to take vitamin D supplements. We stock several forms for our patients’ varying needs. Choose the best one for you – and ask if unsure. They are all vitamin D3, by the way, no D2 at all.

Suggested adult use:
2,000 to 5,000iu per day for health maintenance.
10,000iu short-term for specific health recommendations.
Suggested child use:
1-5 yrs old - 1000iu
6-12 yrs old - 2000iu

Vitamin D3 caps 5000iu (Vitamin Research)
The simplest solution; one-per-day for an adult (and it won’t matter if you miss the odd day) 5000iu per capsule 120/bottle £18.50
Cost per month (4,000iu per day): £3.70
Non-Medicinal ingredients: microcrystalline cellulose, hydroxypropylmethylcellulose, vegetarian capsule

Vitamin D3 caps 1000iu (Vitamin Research)
The lower-dose equivalent, for children or those who need to fine-tune their intake 1000iu per capsule 250/bottle £14.69
Cost per month (4,000iu per day): £7.05
Non-Medicinal ingredients: microcrystalline cellulose, hydroxypropylmethylcellulose, vegetarian capsule

Bio-D-Mulsion Forte (Biotics Research)
The cheapest, and just 2 drops per day. May not be suitable if you have food or chemical sensitivities 2000iu per drop 750drops/bottle £16.10
Cost per month (4,000iu per day): £1.28
Non-Medicinal ingredients: sesame oil, acacia

Vitamin D3 liquid (Advanced Orthomolecular Research)
Easy to give the right amount to children, and with less risk of allergy problems 1000iu per 0.2ml measure 250 doses/bottle £27.00
Cost per month (4,000iu per day): £12.96
Non-Medicinal ingredients: medium chain triglycerides (from coconut), "-tocopherol (from soya)

Available through www.naltd.co.uk
Tel. +44 (0)20 7099 6003 / +44 (0)1904 691 591   enq@naltd.co.uk

Click here for more articles

First Published November 2009

Click here for LINKS to manufacturers of nutrition and food supplements.

Back to top