The specific kind of vitamin D that's more effective and what you need to combine it with, especially after the menopause

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Winter is the season of colds, flu and illness. Joy. The lack of sunlight also makes it the depths of low vitamin D  season, Public Health England advise that every adult in the UK take a 10mg supplement from October to March. Around 20 per cent of us are estimated to be severely lacking in vitamin D, which we need to absorb calcium, magnesium and phosphate, essential for maintaining strong bones and teeth. It turns out, however, that one form of vitamin D in particular, D3, is more effective. Not only that, but combining D3 with another much-neglected micronutrient, vitamin K2, gives a better boost for bone health.

Why D3 is the key

Vitamin D isn’t a solo act - it’s a family. The two key players being D2 and D3. According to Dr Clare Morrison of online doctor and pharmacy service MedExpress : "D3 is the most effective and important form of the vitamin. The best dietary sources of vitamin D3 are oily fish such as mackerel and salmon, fish oil, eggs (particular the yolks), liver and butter. In addition, the body makes its own D3 when the skin is exposed to direct sunlight."

In a relatively sun-starved nation, getting our vitamin D fix from the sun seems fanciful, so sourcing the most active and usable form of vitamin D from our food is a good move according to Dr Morrison.

You’ll no doubt have clocked by now that edible D3 is derived from animal sources. So what if you're vegan? The other main form of the vitamin, D2, comes from plants. It’s most commonly sourced from mushrooms that have been grown under UV light, and as it’s cheaper to produce. It’s, therefore, the most common form of vitamin D found in fortified foods such as bread and cereal as well as in many supplements.

While D2 is certainly not to be sniffed at, D3 has been shown to be almost twice as effective at raising vitamin D levels overall in the blood. Some studies also suggest that vitamin D2 supplements are more prone to degradation than vitamin D3 options, but conclusive evidence is required.

Many supplements are vegetarian with the D3 sourced from lanolin, such as Better You DLux Vitamin D and K2 Spray £9.95  or Vitabiotics Ultra Vitamin D 1000IU, £5.10  but there is also a vegan option in  Nutri Advanced Vegan Vitamin D3 drops , £13.15. As vegans are often lacking in vitamin D, good supplementation is especially important. The D3 is derived from lichen and suspended in medium chain triglycerides to aid absorption.

Whether you’re taking D2 or D3, considering an oil-based supplement is advisable as vitamin D is a fat-soluble micronutrient. Diet-wise this means adding a bit of butter or oil to your eggs, which is the kind of delicious health tip we welcome. The thing is, a fry up alone probably won’t cut it if the latest research into dosage is concerned…

You might need more D than you think

Dr Paul Clayton , the world’s leading expert in pharmaco-nutrition and Director of Science for ‘super supplement’  Lyma  (which also contains the vegetarian form of D3 derived from lanolin) told us that 2000 international units (i.u, equivalent to 50mg) of vitamin D3 is in fact considered the optimal dosage. Studies show that this daily dosage cuts the risk of  breast cancer , colon cancer and type 1 diabetes  in half, and Dr Clayton emphasises that totting up this D3 hit without a good supplement would be quite a tall order:

“These quantities of vitamin D could be achieved through exposure to sunlight, but there's a catch; it would need to be full upper body exposure, for an hour or so, on a very sunny midday; every day.

“The vast majority of us do not achieve this due to work (usually indoor work), clothing, sunblock (because everyone is afraid of skin ageing and cancer), and living in a temperate zone where the sun is never very strong.”

So a supplement can give you a distinct D3 leg up, but a double vitamin act may prove even more effective.

Why D3 and K2 are friends

Dr Clayton explains the relationship:

“Vitamin K2 and D3 are an important combination for bone health, and more specifically for maintaining or improving bone mineral density.

“Vitamin D is ineffective on its own, because although it encourages calcium availability (as well as many other things), the calcium cannot be built into bone unless K2 is also present. In technical terms, K2 activates the bone protein osteocalcin, so that it can bind calcium (and magnesium), thereby transforming osteoid (pre-mineralised bone) to mature, mineralised, load-bearing bone.”

It’s for these bone bolstering qualities in particular that a D3 K2 vitamin duo is particularly important for post-menopausal women , when bone density typically decreases due to a drop in oestrogen levels . Dr Clayton advocates adding a high-quality D3 and K2 containing supplement to your diet as vitamin K is also typically elusive in food (even a healthy, balanced diet to likely to yield only 25% of our RDA of vitamin K2):

“Vitamin K2 is not found in many foods; other than natto  (common in Japan) and quark (a Dutch soft cheese). This is one reason why osteoporosis  is so common. The rationale for consuming more K2 and D3 together is therefore strong given that so many of us are also deficient in vitamin D too.”

Given the widespread research indicating that many of us of want for vitamin D, is it possible to have too much of a good thing? And how can you tell if you definitely are deficient?

Can you OD on D3?

While you can’t ‘overdose’ on vitamin D3 by way of sunlight (your body will simply stop producing it), Dr Morrison explains that you can have too much of a good thing in terms of supplementation:

“It's important not to exceed the recommended dose of vitamin D3 on the bottle, as too much will cause a buildup of calcium in the body, potentially leading to kidney stones, weakness, thirst, vomiting and confusion.”

As long as you stick to the dosage instructions, however, you shouldn’t encounter any issues. As for knowing whether you’re truly deficient in the first place, Dr Morrison underlines that “mild deficiency doesn't usually cause symptoms, but more severe cases can cause fatigue, depression and pain in the bones and muscles. If you think you may be deficient, see your doctor, who could arrange a blood test if necessary.”

Otherwise, K2 + D3 = harmony.

Disclaimer: Certain supplements are used for different reasons and a one-size-fits-all approach should never be adopted. In addition, pregnant women and anyone on medication should always consult a doctor before embarking on a supplements programme.

Lyma prices start from £149,  buy it now

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