Good Day Sunshine Trivia Quiz

Answer: Sunblock

Sunblocks do not block all rays from the sun; according to the Skin Cancer Foundation, no product does this. They actually serve the same purpose as a sunscreen, limiting (but not completely preventing) the penetration of dangerous rays from the sun. Suntan lotions are meant to help acquire a tan; most do not provide any protection against harmful rays or provide such a low amount of protection that they cannot be considered to be sunscreens.

Answer: UVA

Sunscreens work by absorbing or reflecting rays. Short wave ultraviolet B (UVB) rays were the original target of sunscreens, since these rays were considered the ones that led to sun damage and skin cancer. Long wave ultraviolet A (UVA) rays have since been found to also be harmful, so the best sunscreens target both types of rays.

Answer: Sun Protection Factor

The Sun Protection Factor (SPF) is a rating system used to indicate the strength of a sunscreen. It theoretically indicates the amount of time that a person can stay out in the sun before burning. Thus an SPF of 15 indicates that a person can stay fifteen times longer in the sun than it would take to get a sunburn without sunscreen.

This is confusing however, since it doesn't take into consideration sweating, water activity or other factors that can affect sunscreen performance. Perhaps the best way to use the SPF measurement is as the percentage of UVB rays blocked by the product, with an SPF of 15 blocking an estimated 94 percent of the rays and an SPF of 30 blocking 97 percent of the rays (American Academy of Dermatology).

Answer: Higher SPF levels are not significantly more effective.

Although you can find higher SPF levels in the most popular common brands (and pay more for them usually), most natural sunscreens do not exceed 30 SPF because higher levels are only slightly more effective. For example, an SPF of 45 is only 1 percent more effective than an SPF of 30 (American Academy of Dermatology).

So why not produce the higher SPF level sunscreens even if the benefits are only slight? One of the main reasons is that the perception that the sunscreens ARE more effective can lead people to use smaller amounts or reapply them less frequently, thus resulting in less protection. Sunscreen industry representatives argue that the fact that people tend to use less sunscreen than recommended is a valid reason for producing the higher level products. Both the American Academy of Dermatology and the American Cancer Society have reported that sunscreens with an SPF of 15 are sufficient if properly applied, but since most people do not use enough sunscreen, an SPF of 30 is frequently mentioned.

Answer: Oxybenzone

Oxybenzone is a common chemical used in many personal care products, such as lotions, lip balms and cosmetics, and most of the popular sunscreens available in stores in the United States contain it. Although it is effective at blocking harmful rays, it has been linked to allergies, hormone disruption and cell damage. Another concern is that oxybenzone is absorbed into the skin and remains there, and the long term effects of the chemical are not known. Not only does it penetrate skin, it is a "penetration enhancer" which means that it helps other chemicals penetrate skin.

Using oxybenzone when swimming in the ocean is also an issue. Studies have shown oxybenzone to be dangerous to marine life, harming coral reefs and resulting in hormonal changes in fish.

Answer: Zinc oxide

Zinc oxide is a preferred ingredient in natural sunscreens because it isn't absorbed into the skin. Most common commercial brands avoid it however, because it is difficult to blend into the skin, resulting in white polka dots in pores. Some manufacturers have taken advantage of this opaque characteristic of zinc oxide and created colored sunscreens with it - remember the neon noses that became popular in the 1980s?

Some of the more expensive brands contain other ingredients that make it easier to rub in, or use nanotechnology to break the zinc oxide into smaller particles that can be more easily blended into the skin. The latter method has its detractors however, as there are concerns that there hasn't been enough research on the effects of the nanoparticles.

Answer: Titanium dioxide

Titanium dioxide has the same pros and cons of zinc oxide but it reflects light better than zinc oxide and is particularly effective against UVB rays, so it is a common ingredient in many sunscreens. It isn't as effective in protecting against long UVA rays, however, so it is usually combined with other ingredients, particularly zinc oxide, in sunscreens.

It is considered to be more opaque than zinc oxide so it does require other ingredients to make it easier to blend into the skin.

Answer: It has a very low SPF.

The average white t-shirt is estimated to only have an SPF level of 3; dark clothes offer better protection (American Academy of Dermatology). Alternatively, sunscreen can be used under clothing, or special SPF clothing can be purchased. Since you are unlikely to apply sunscreen to your head (unless you're bald), wearing a hat is particularly recommended.

Answer: It causes vitamin D deficiency.

The National Cancer Institute in the United States admits that there isn't conclusive scientific evidence that sunscreens have decreased the incidences of skin cancer. Some studies have supported the success of sunscreens, but there has been criticism of the designs of the studies. However the amount of skin being exposed to the sun has increased since sunscreens were first introduced, so the lack of evidence of the efficacy of sunscreen at this stage in the sunscreen cycle isn't necessarily surprising.

Since vitamin D is a benefit of sun exposure it perhaps also isn't surprising that some sources claim that sunscreen leads to a vitamin D deficiency. The Skin Cancer Foundation however points out that most vitamin D is acquired through foods and dietary supplements, and the National Institute of Health in the United States indicates that a minimal amount of sun exposure each week produces adequate vitamin D production.

Answer: Many contain hazardous chemicals.

Comedian Lewis Black has ranted that we'll someday find out that it is sunscreen that causes cancer, and some sources believe this is the case. The Environmental Working Group found that all sunscreens they tested have some risk, with many of the most popular brands containing hazardous and in some cases, carcinogenic, chemicals. They rated over 1700 sunscreens, providing rankings of the most safe and most effective brands. The database of results can be accessed on their website.

The Skin Cancer Foundation has criticized the study because it might drive people not to use sunscreen, but the advice of the Environmental Working Group was to "always use sunscreen". Their stated purpose was to allow consumers to make informed decisions on their sunscreen purchases and to motivate companies to produce safer products.