Want to stave off a cold or flu? Take some vitamin D supplements, according to experts.

Studies suggest that taking the supplements protects against acute respiratory infections.

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Holland & Barrett nutritionist Elizabeth Wall commented: “The new research follows on from changes in the Government guidelines last year which now recommend every person in the UK take a minimum of 10 micrograms of vitamin D per day, throughout the winter period and for those considered to be in ‘at risk’ groups such as during pregnancy, the elderly, young children and those from ethnic origin with darker skin to take it all year round because we may not get enough sunshine in this country to make the right amount of vitamin D in our bodies naturally.

Known as the 'sunshine' vitamin, it could have benefits beyond bone and muscle health and protect against acute respiratory infections.

Results of the study fit with the observation that colds and flu are most common during winter and spring, when levels of vitamin D are at their lowest.

Consultant Endocrinologist Professor Stephen Davies commented on behalf of Fultium Daily D3: "Vitamin D is more widely known as the 'sunshine' vitamin, as 80-90% is produced from skin when exposed to sunshine. However, the sun is only strong enough in the UK for our bodies to produce vitamin D from around late March to the end of September between 11am and 3pm.

"Even then, there are several varying factors which can affect the body’s ability to manufacture vitamin D such as cloud cover, the amount of skin exposed and sun cream.”

So as well as taking vitamin D supplements, how can you increase your vitamin D intake without going to live on the Costa del Sol? Here are 6 ways:

1. Eat oily fish

Salmon, mackerel, herring and sardines - one 112g fillet of mackerel contains 18mcg of vitamin D, an 85g fillet of cooked salmon has 11.2mcg...

2. Eat eggs

One poached egg contains 1.025mcg of vitamin D.

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3. Other sources

Red meat and to a lesser extent, mushrooms and cheese - 1oz of Parmesan contains 2% of your daily requirement.

4. Cereals

Vitamin D and other vitamins and minerals are also added to some breakfast cereals, infant formula milk, fat spreads and non-dairy milk alternatives.

5. Those at risk

As well as babies and young children, some people are at greater risk of not getting enough vitamin D, and the Department of Health recommends that people who aren’t often exposed to the sun (eg the frail or housebound, people in an institution such as a care home, or people who usually wear clothes that cover most of their skin), should take 10 micrograms of vitamin D supplements daily.

6. Daily supplements

Everyone over the age of five years (including pregnant and breastfeeding women) is advised to consider taking a daily supplement containing 10 micrograms (mcg) of vitamin D.