I just wanted to share a very recent experience I had while cycling. My old helmet had a manufacture date of 3/2012, so I figured that I was probably due for a new one. Some people recommend a new helmet every 3- 5 years depending on how much it has been used. UV, sweat etc., can break down the styrofoam over time and it can become brittle and less protective. I purchased a new Specialized Prevail helmet about a week ago, based on the recommendation of the store manager, who said: "if you were to get into an accident, this is THE helmet you want on your head". Little did I know how prophetic that would become! It's not cheap at around $230, but boy does it ever work!
Yesterday afternoon, I went for a ride and one minute I was fine, when suddenly I became airborne and went up and over my handlebar landing on my forehead and face. (I hit one of those low concrete car barriers, that I didn't notice, while distracted)) The impact (of my 200 lb, plus body) cracked the front of my helmet and I only suffered some abrasions on my face hand, a banged a knee and sustained some forearm soreness. Also, one of the lenses of my new sunglasses got scratched, but they likely helped further abrasions on my face. The handle bar is bent, but my bike is in fairly good shape, considering.
I have been in several biking accidents over the years, but this is the first time I have landed on my head. I truly believe that my old helmet would not have protected me as much and I would have suffered far more injury. And if I had not been wearing a helmet, well...my skull would have likely cracked and I would be in the ER. I have already placed an order for a new "Prevail" helmet.
Moral: Make sure your helmet is not too old and buy the best one you can afford. Ride safe!