Does a caffeine product have the same effect as a cup of coffee?

Yes and no, depending on your expectations. Take the product Shower Shock, which is marketed as caffeine-infused body wash that provides a wake-me-up equivalent to two cups of caffeine when you use it in the shower. So, should you expect some invigorating benefits?

Yes, if you'd like to spend one hour in the shower, without rinsing off, writes Anna Jane Grossman for the New York Times. And that’s just equal to one cup of coffee.

Also common are products with a coffee-like aroma, including lip glosses, creams and scrubs. But do they really give you the jolt you need? Getting a whiff of these beauty products might make you more alert, but that's only because of your expectations: It's a learned response for us to connect coffee with feeling energized.

Can caffeine reduce cellulite?

After research published in 1999 suggested that "caffeine-based liposome-encapsulated cream reduced the thickness of fat," a slew of cellulite creams containing caffeine hit the market, writes Grossman. And so the question of whether cellulite creams are truly effective has naturally followed.

Unfortunately, the research has been inconsistent. According to dermatologist Michelle Rivera, M.D. in The Washingtonian, there's no research to support that caffeine actually "works on cellulite." "Caffeine is simply not absorbed by the skin; it's like trying to shove an elephant through the eye of needle," explains Dr. Rivera.

On the other hand, some research suggests caffeine produces effective results. In a study from the Journal of Cosmetic Dermatology, 80 percent of 130 women who used a caffeine solution for 30 days saw a reduction in skin dimpling, their skin appeared tighter and they lost 2 cm off their thighs.

Whether caffeine creams banish cellulite is arguable — and an area that needs more research — but they do seem to help its appearance; caffeine dehydrates fat cells, giving skin the appearance of smoothness, Linda Wells, Allure's editor-in-chief, tells The Early Show.

If you'd like to try a cellulite cream, consider Pevonia Body-Svelt Gel or Bliss Fat Girl Slim.

Is caffeine effective in eye creams?

Caffeine can reduce puffiness, redness and dark circles. It works by draining excess lymph fluid and blood short-term, according to Wells. Try Murad Moisture Silk Eye Gel and Murad Essential-C Eye Cream, SPF 15, which help to diminish puffiness and even fine lines.

What about skin conditions?

Caffeine products can also help those with rosacea, explains dermatologist Leslie Baumann, M.D., for Yahoo! Health. The key lies in caffeine's ability to constrict blood vessels, something that people with rosacea can't do: "Caffeine can be a tremendous boon to those who suffer from rosacea, which is essentially caused by frequently dilated blood vessels that lose their ability to contract," writes Dr. Baumann. She recommends those with rosacea try La Roche Posay Rosaliac Anti-Redness Moisturizer.

Can coffee prevent skin cancer?

Recent studies suggest caffeine might prevent UV damage. Scientists at Rutgers University found that after exposing two groups of mice to UV rays, the group that received the caffeinated lotion developed over 40 percent less cancerous tumors than the group that wasn't treated with the lotion.

Does drinking coffee benefit skin?

Coffee is packed with antioxidants that fight free radicals and reverse cellular damage. In fact, research from the American Journal of Clinical Nutrition suggests one serving of coffee contains more antioxidants than a serving of fruit, including oranges and blueberries, writes beauty expert Sue Chung for Health Central.

To get the most benefit from your coffee, experts recommend drinking your cup o' joe no more than 20 minutes after it's been brewed. That's because, after 20 minutes, coffee starts to oxidize and loses its nutritional benefits.

Those with dry skin shouldn't drink more than a cup a day, because coffee is a diuretic and can cause the body to lose moisture. Dehydration can also accelerate wrinkles. One option is to switch to green tea, which has all the antioxidants found in coffee — and then some — with less caffeine.