Vitamin D

Can we get enough vitamin D in Mushrooms to help us meet our dietary requirements? We will take a closer look in this post. The British Dietetic Association recently changed their recommendations on people taking vitamin D supplements. They now advise that all adults and children over the age of one should consider taking a daily supplement containing 10 micrograms (µg) of vitamin D especially during autumn and winter¹. This is because low vitamin D levels in children can cause Rickets, a bone deformity and in adults it can cause Osteomalacia, a softening of the bones. The recommended vitamin D requirement is 10µg per day for over 4 year olds¹.

Where do we get most of our vitamin D from?

We do get the majority of our vitamin D from sunlight and spending time in the weak sunshine that we get in the UK is a great way to soak it up via our skin. The sunshine during the summer months in the UK is strong enough to do this. However, with fears of skin cancer and applying sun lotion to our skin, we are less likely to absorb it and people with a dark skin pigmentation will also struggle to get adequate vitamin D from the sun exposure in the UK.

Whilst taking supplements is very helpful for some people with chronic illnesses, wouldn’t it be better if we got most of our vitamin D from natural sources instead? A few decades ago, many people took cod liver oil capsules to top up their intakes of vitamin D and we know that oily fish are good sources of vitamin D. British people only tend to buy 5 types of fish: salmon, tuna, cod, haddock and prawns. Only salmon and fresh tuna are classed as oily fish, so buying and eating them twice a week would put huge strains on our fish stocks. Including other oily fish into your diet such as Mackerel, Sardines and Pilchards can be helpful to increase your vitamin D intake.

Let’s eat more mushrooms!

So, let’s eat more mushrooms instead! Tesco have recently started selling mushrooms high in vitamin D². We should encourage other supermarkets to do the same. Tesco’s range includes Chestnut, baby chestnut and Portobello mushrooms and they are produced by being grown in the dark and then they are exposed to UV light for a short period. The ergosterol that mushrooms contain creates a good form of vitamin D when they exposed to this form of light³. Tesco’s claim that only a small portion of 100g of the mushrooms can provide 5 µg of the vitamin, which is already half of your requirements. This equates to 4-5 chestnut mushrooms, 1-2 portobello mushrooms or 14 baby mushrooms. A delicious way to get vitamin D in mushrooms all year around!

Please contact your local supermarkets and tell them that you would like to buy some vitamin D fortified mushrooms. This can be done via email and the supermarkets often have their customer email on the front page of their website. Otherwise, customer service desks can give you a telephone number to call. The more people that do this, the more likely that they will put pressure on their suppliers to fortify their mushrooms.

In order to obtain the other 5µg, there are other foods that are fortified with vitamin D. These include breakfast cereals and yoghurts. 1 47g pot of petit filous has 1.35µg of vitamin D (the big pot 85g has 2.5µg) and a 30g bowl of Rice krispies has 1.3µg. Some mineral waters that contain 2µg of vitamin D in 100ml are being sold and a portion (10g) of margarine contains 0.75µg. Some yeasts to make bread can also produce it and 2 slices of bread containing this yeast provides 0.60µg. A cooked egg will provide around 1.5µg of the vitamin and a 90g portion of pork will give another 0.9µg. Now you can appreciate how much higher in nutritional value mushrooms can be! It’s time to enjoy a mushroom omelette, mackerel on toast or a pork stroganoff!

Please note that it is possible to exceed the recommended amount of vitamin D from supplements. Therefore, do not take more than one supplement containing vitamin D (including cod liver oil). It is still important to apply sun cream to your skin, particularly when the sun is high in the sky during the summer months. If you do not like mushrooms or other fortified foods, we would recommend that you take a supplement, particularly during the winter months.

We hope you enjoyed this article, do take a look at more of our healthy eating posts, thanks.


1 – BDA food factsheet on vitamin D
2 – Tesco News Release “Mushrooms enriched with vitamin D to help keep you healthy during the darker winter months”.
3 – Raphael-John H. Keegan et al. Photobiology of vitamin D in mushrooms and its bioavailability in humans.   Dermatolendocrinol. 2013 Jan 1; 5(1): 165-176.