Use your head!
Aaron Roe casts his eye over 10 bike helmets certain to keep you safe and cool on the roads this summer
It's not illegal to ride without a helmet, but anyone who's taken a nasty tumble on the road will have been thankful they were wearing one. Studies claim they can reduce the risk of a fatal head injury by 65%.
Thankfully, we managed to stay on our bikes while testing our selection, so we can't tell you how they hold up in a crash, but they all carry the CE mark, which means they meet European safety standards.
Some include MIPS (multidirectional impact protection system), which offers additional protection by reducing rotational forces in an impact.
Others incorporate Koroyd - closely packed tubes which crush down in a crash to absorb energy and protect your skull.
When choosing a new helmet, don't forget to measure around your head to get the correct size.
All of these models are suitable for both sexes, but it's always worth trying out a few shapes and styles before you buy because the fit can be quite personal.
Don't get too hung up on weight - the most comfortable helmet isn't always the lightest - but make sure you find one that suits your style of riding. It's pointless spending hundreds of pounds on a featherweight helmet and then subjecting it to the rough and tumble of a daily commute.
POC omne air spin: £140, Sigma Sports
POC are famous for their oversized lids, including the Ventral and Octal.
This new offering dials down some of their more outrageous design aspects to give it a broader appeal.
It's aimed at gravel riders, road racers and commuters - one helmet to rule them all.
We love the rounded design and the hardshell finish. It's a great fit too, with nice thin straps and a highly adjustable retention cradle.
It comes with a storage sack and in a wide range of colours, including the classy blue we tried out.
dhb aeron road: £42, Wiggle
Flip this one over and you'll discover its secret - the label reveals it was made in Italy by Kask, purveyors of quality helmets to the Ineos racing team.
Despite the bargain price, it's a great fit - nicely padded and with a dial-adjustable cradle that folds under to make it easier to store on a shelf.
Okay, the design, with its pointy bits and multitude of vents, might look a bit dated and the edges of the hardshell aren't as well-finished as some in our round-up, but for under £50 it's a steal.
Met trenta 3k carbon road cycling helmet: £209, Tredz
If you've spent a fortune shaving grams off your bike, you'll want an equally pared-down helmet to top things off.
This lightest version of Met's trenta, released for the Italian firm's 30th anniversary, is built around a carbon fibre cage.
It maintains structural strength while keeping the weight down to a skinny 222g for a medium size.
The semi-aero design cuts through the air while offering plenty of ventilation thanks to its 19 holes.
The straps offer plenty of scope for adjustment and the frame holding the rear tensioning wheel can be moved up or down to find your perfect position.
It's pricey, but we found it super-comfortable and so light we hardly noticed we were wearing it.
Lazer century helmet: £101.98, Halfords
One hundred years of knowhow went into this design - hence the name.
It's got great features, including a built-in rechargeable rear light and a magnetic twist cap panel you can pop off and flip around to adjust airflow and ventilation by a claimed 11%.
The light is fiddly to access but offers a bit of extra safety, especially in low light.
We found the fit to be superb thanks to great padding and a sturdy retention system that is adjusted by a dial at the rear.
The plastic shell comes in six colours and you also get a carrying sack.
Abus airbreaker road helmet: £229.99, Tredz
Here's one of the helmets the top-flight Movistar squad are wearing this season.
It's light at just 213g in a medium size and well ventilated.
Minimal padding helps to keep the weight down, yet it still feels comfortable in use.
A nice touch is the plastic mesh towards the back of the ponytail-compatible design - it helps with the aerodynamics and if you pour a bottle over your head pro-style on hot days, it retains some of the water to keep you cool for longer.
Endura pro SL helmet: £142.49, Wiggle
The boldly styled pro SL is a member of the prestigious club where the risk of a skull fracture in a crash falls to below 5% (the standard required for CE certification is 40%).
It uses a honeycomb of Koroyd tubes to offer excellent protection while also keeping weight down to just 239g for our medium size.
We thought it was going to prove hot in use, but the combination of large vents and the angle of the tubes actually kept us very cool.
There's a nicely cushioned washable pad for added comfort and the adjuster assembly at the rear can be moved up or down to find your ideal position.
New for 2019 is this eye-catching rainbow colourway, which should certainly turn heads among your cycling companions.
Specialised s-works prevail II ANGi: £200, Sigma Sports
You'll have seen this distinctive helmet worn by some of the best racers on the planet in tour events.
It's the lid riders such as Peter Sagan turn to when the weather gets hot and the roads head skywards.
There's a wide air intake up front plus plenty of exhaust ports to help with cooling.
The ANGi in the title is a clever little device which connects to your phone via Bluetooth and then calls your designated contacts if you fall off.
Its other big safety feature is the new MIPS-SL system.
It uses sliding pads rather than the original MIPS plastic liner, helping to keep the weight down to a none-too-shabby 228g in a medium size.
Giro synthe MIPS: From £130.99, Chain Reaction
If you want something small and neat that fits well and won't break the bank, this could be the one for you.
We love the swoopy look of the outer shell and its perforated panels. The addition of MIPS means it's safe and stylish.
It's got loads of vents to keep you cool, yet is designed to give the best aero helmets a run for their money when it comes to slipping through the air.
We particularly like the matte purple number with its chevron pattern.
Smith Trace MIPS road helmet: £199.99, Wiggle
There's a Star Wars stormtrooper vibe about this top-end design from America.
As well as having futuristic looks, it's super-safe, with both MIPs and Koroyd protection.
As you would expect from a company that made its name creating optical wear, there are channels to hold your sunglasses securely.
We found it to be a great fit and you can buy it in a range of colours.
Oakley ARO 5 road helmet: £139, Sigma Sports
This aerodynamic design incorporates a handful of larger vents to keep you cool while working hard.
We love the way it uses a Boa dial and lace - as featured in some of the fancier cycling shoes - to tighten the cradle evenly right around your head.
It makes for a really comfy fit and doesn't get fouled on your sunglasses either.
Brow pads can get whiffy on helmets, but the X-Static model on this one uses a sprinkling of silver to fight odours.
At 312g in a large size with MIPS, there are lighter helmets, but you won't find many that are more comfortable.
Any of our selection will serve you well out on the roads, but particular favourites were the small and neat Giro and Abus models and, of course, our best buy: a great all-rounder from Sweden's POC.