Casey Clarke, left, and Nicole Rankin from Veggies Unlimited show off some of the range of mushrooms.

Casey Clarke, left, and Nicole Rankin from Veggies Unlimited show off some of the range of mushrooms.

MUSHROOMS love the dark, but leaving the fresh fungi in the sunlight will give you a rich source of vitamin D.

According to the latest research at Sydney University, mushrooms exposed to just one hour of natural sunlight can give adults 100% of their vitamin D needs after being consumed. Vitamin D is great for fighting infection and even preventing heart disease and type-two diabetes.

So now is the time to get more mushies in your trolley, leave them on the bench so they get some sun, and then get cooking.

With more than 10 years of experience in the green grocer game, Veggies Unlimited's Nicole Rankin knows how to compare mushrooms with mushrooms.

"Button mushrooms would be our most affordable... they are probably the most popular," she said.

"Your button mushrooms will give you a whiter sauce in your cooking," she said.

Also popular are the flat mushrooms, which can create a rich, dark sauce colour, she said.

But with the rise in hot-running reality TV cooking shows, more and more consumers are stepping outside their comfort zone when it comes to buying fresh food.

Shitake, Enoki, oyster and Swiss Brown mushrooms have become more popular over the years, she said.

Ms Rankin describes these little fungi as the "fancy mushrooms".

"They are great in stir-frys... or mixed through salads," she said.

Accredited practising dietician Glenn Cardwell said the new research was a real breakthrough in nutritional science and this small change may help the millions of Australians overcome their vitamin D deficiency.

"After one hour in direct sunlight, your mushrooms won't diminish in flavour or appearance but will have adequate vitamin D levels."