When I was young, I had some very strong objections to wearing my bicycle helmet. It was heavy, made my head hot, messed up my hair and didn't look cool! Despite my numerous complaints, my parents refused to let me ride my bicycle without my helmet. I suppose they were concerned with silly things like my physical safety. The fact of the matter is that bicycle helmets save the lives of people every day. They are the most essential piece of safety equipment a cyclist can wear, and as breakthroughs continue to be made in how to protect cyclists, helmets continue to evolve.

As in many other sports, people did not consider safety equipment to be necessary in cycling for a long time. Although the bicycle was invented in the early 1800s, it was not until the 1970s that cyclists began to wear helmets. This is partially due to the fact that prior to that decade, bicycles were regarded primarily as children's toys. Despite the fact that children could and did find themselves involved in accidents, the pastime of riding a bike not considered dangerous enough to require safety equipment. For the most part, the only time an American adult rode a bike was to participate in bicycle racing. And although these cyclists did wear bicycle helmets, the helmets of the era offered minimal impact protection.

Then, in the 1970s, numerous adult Americans took up cycling as a form of recreation, exercise and even commuting. The oil crisis of that decade made bicycle commuting a fairly attractive option from a financial standpoint. This surge in popularity led to the development of the first modern bicycle helmets. The first modern helmets had interiors made from expanded polystyrene foam, a material used to make liners for motorcycle and motorsport helmets. The shells of these bicycles helmets were of hard polycarbonate plastic.

Early bicycle helmets had little ventilation, which was due mainly to the technical limitations of the foam and plastic shells. This problem continued until the early 90s, at which time the in-mold microshell technique was invented. This kind of helmet consisted of a very thin shell incorporated into the helmet during the molding process. In-mold microshell helmets could be created in more complex shapes, which allowed for larger vents and better airflow. This technology quickly became dominant in the industry, all but replacing the foam-and-plastic helmets.

Since the invention of in-mold microshell helmets, designers have continued to refine the shape and capabilities of bicycle helmets. Recent improvements have included advances in fitting and retention systems. Early bicycle helmets had thick pads that cradled the head, but modern helmets can be adjusted to fit the cyclist's head precisely, making such pads unnecessary. This makes the helmets much lighter and much less warm, a major asset when cycling. Additionally, some more advanced helmet models feature carbon fiber inserts that increase the helmet's strength and protection capacity. Such helmets are especially popular among racing cyclists, who also tend to favor helmets with long, tapered backs, which are designed to be aerodynamic.