This could be the reason you’ve started feeling tired all the time

Blame summer...

Summer may signal long balmy days and endless nights of fun; summer nights and all that (soz if you now have the Grease song in your head), but if you're wondering why you're more sleepy than usual in the hotter months, Vitamin B12, or lack thereof, may well be the cause...

Whilst it's relatively easy to get your quota of B vitamins through eating a healthy diet - think plenty of fresh fruit and veg, wholegrains, meat and fish (these are also great Vitamin D foods), Vitamin B12 is harder to come by, and is actually one of the most crucial of all the B vitamins when it comes to overall health and energy levels. Dr Marilyn Glenville, one of the U.K’s leading Nutritionist explains, 'at its most basic level, the food you eat and drink is the fuel that your body and brain needs to function at its peak. Skimp on the quality of that fuel and you will pay the price with weight gain and low energy.'

Vitamin b12 deficiency

If you haven't heard of Vitamin B12 before, then you're not alone (we didn't know the importance of it until recently either), and while you may be reluctant to add yet another supplement to your shelf, it could hold the key to a more energised, less sleepy version of you.

Vitamin B12 is actually only found only in animal foods, which means if you’re a vegetarian or vegan, a lack of this vitamin could be the reason your energy levels are low and you're feeling lethargic. According to nutritionist Cassandra Barns, 'Vitamin B12 is one of the many nutrients we need for energy. Its roles include helping to build red blood cells that carry oxygen to our cells to make energy. In fact, it’s just as important as iron for this! Deficiency in vitamin B12 can be relatively common, firstly because it’s only found in animal foods, and secondly, some people may not absorb it very well from their food. For those lacking B12 for one of these reasons, taking a B12 supplement can be beneficial, if not essential, to keep their energy levels up.'

Nature’s Plus Source of Life Garden Vitamin B12 (£17.50 for 60 capsules, www.naturesplus.co.uk) is a nutritionist- recommended supplement, and is helpfully organic, vegan and gluten-free.

‘It provides an effective dose of B12 in the active form of methylcobalamin, meaning it can be easily used by the body. It also provides a range of other B vitamins, which work together with vitamin B12 to give us energy. And it’s certified organic, so you know you’re getting a good-quality product,’ explains Cassandra.

Alternatively, you could try the latest B12 craze, and follow in the footsteps of Rihanna by getting injections of Vitamin B12 to fight off exhaustion, but TBH, we think we'll stick to getting our daily dose in capsule form.