Everyone knows at least one person who can't get through the morning without a cup of coffee.

Many college students rely on this substance to start the day or keep them awake for all-night study sessions.

Caffeine is a mild central nervous system stimulant.

When taken in moderate amounts, it can boost energy and heighten alertness.

It is found in coffee, tea and cigarettes and can be bought in pill form -- a legal drug that is readily available and generally safe.

But caffeine might have irreversible side effects.

According to the American Medical Association (AMA), women should pay close attention to the amount of caffeine they consume.

Too much caffeine may cause fertility complications, increased risk of osteoporosis and breast tenderness.

Although overall evidence concludes that moderate consumption (approximately 300 mg daily) is safe, women should still be informed of possible complications from this tasteless and odorless drug, according to the AMA.

"If I don't have coffee, I'm tired and cranky, and it's hard to concentrate," Elli Wilson (senior-human development and family studies) said.

Wilson cut back from her usual six-cup-a-day habit to two.

She has noticed a difference in her health.

"If I drink excessive amounts, my hands shake and I get a bad headache," she said.

"It's difficult to get the right balance because if I don't get enough or I get too much I can feel the effects.'

Most women don't know about the possible long-term side effects.

"I know that it dehydrates you and it's not good for your teeth," Kelly Tarczy (senior-Spanish and international politics) said.

She said she drinks it more consistently at college, usually one or two cups throughout the course of the day.

The AMA, although continuing research on the effects, cannot make a direct link between caffeine and these side effects.

Outside factors such as age and medical history may also play a role in some problems people face.

Even though there are not direct links, experts suggest reducing caffeine intake during pregnancy because caffeine is able to permeate breast milk and excessive amounts may be harmful to young children.