Are you getting enough Vitamin D?
With winter solstice behind us, the days should be getting longer now. At least in theory. But when the sun continuously sets just past 4pm, it's hard to imagine longer stretches of daylight returning to our lives anytime soon. And with so little daylight to play with, it can be difficult to get outside and snag the sunlight needed to quench your daily Vitamin D requirement, especially if you work in a 9-5 job.
Vitamin D is essential to good health, keeping bones and teeth strong and healthy. It's also an important player in immune function1 and low levels of Vitamin D have been linked to conditions such as Parkinson's Disease, Multiple Sclerosis, type 2 diabetes and Heart Disease2. But if you can't swing the requisite outdoor time to get your Vitamin D via the sun, how can you make sure your keeping your levels topped up? It's recommended that males and females aged 1 - 70 consume 600 IU of Vitamin D daily. But Vitamin D is hard to come by in most foods, in fact there are only a handful of sources of this important vitamin.
Salmon has been proven to be possibly the richest food source of Vitamin D. Wild salmon in particular. A 100g serving contains nearly 1000 IU of Vitamin D3. Over 65% more than the recommended 600 IU. Other fish to consider include farmed salmon, trout, tuna, sardines and mackerel.
In the USA, milk is fortified with Vitamin D to help combat Vitamin D deficiency. In Britain, our milk doesn't go through the same process, however there are some places you can get foods fortified with Vitamin D, such as Marks and Spencer whose Simply more range includes Vitamin D fortified milk4. Certain cereals are also fortified with Vitamin D such as Corn Flakes.
Though not high in Vitamin D, you can find small amounts of it in eggs. The Vitamin D is sourced from the yolk and not the white, so make sure you're not just eating the whites. A single egg should provide approximately 40 IU of Vitamin D5.
Mushrooms, like human skin, can covert UVB rays into Vitamin D. And even better, they can provide almost an entire day's worth of Vitamin D in a serving. There is nevertheless, a catch. Mushrooms need to be exposed to sunlight in order to reap the Vitamin D rewards. Most commercial mushrooms are produced in dark warehouses and when bought will unlikely provide any worthwhile Vitamin D. However, a study has concluded that any mushroom can produce Vitamin D, even after they're picked, provided they're exposed to the sun before eating. The study recommends exposing mushrooms to daylight for up to 60 minutes between 11am and 3pm. Unfortunately this will only work during the spring and summer months when UV rays are strongest6.
Like all vitamins, you find supplements for Vitamin D in most pharmacies. There are two types of Vitamin D supplements you can get, Vitamin D2 and Vitamin D3. Vitamin D2 is derived from plants, whereas Vitamin D3 is derived from animals and is the same Vitamin D your body produces. There have been studies surmising that Vitamin D2 is less effective than D3 and Vitamin D3 is recommended as the choice for treatment of Vitamin D deficiency by the national osteoporosis society7.