Whether you’re a die hard, morning coffee drinker, or just have a cup every now and then for an afternoon pick-me-up, there’s always that sweet spot of how much coffee is just the right amount. While just a bit can give you the energy you need, too much can make you anxious and jittery.

So is coffee good for us or not?

In short, an average 3-5 cups of coffee, or up to 400 milligrams is just fine.

For years, coffee was thought to be a carcinogen, but it’s been proven to actually reduce the risk of mortality. According to the British Medical Journal, moderate coffee drinkers have been shown to have less cardiovascular disease, and less premature death from all causes, than those who skip the beverage.

In addition, experts say some of the strongest protective effects may be against Type 2 diabetes, Parkinson’s disease, and liver conditions such as cirrhosis, liver cancer and chronic liver disease.

The reason coffee is beneficial might come from its polyphenols, which are plant compounds that have antioxidant properties.

However, coffee is not for everyone. The concern with coffee drinkers is overconsumption, especially when it comes to expecting mothers. The safety of caffeine during pregnancy is unclear, and while the reasearch on coffee’s impact on health is ongoing, most of the work on the field is observational. It is not known for sure whether coffee is the cause of the previously mentioned health benefits.

The way coffee is prepared also affects its compounds, but the research on it is not clear. Roasting, for example, reduces the amount of chlorogenic acids, but other antioxidant compounds are formed. Espresso has the highest concentration of many compounds because it has less water than drip coffee.

“The one coffee we know not suitable to be drinking is the boiled coffee,” said Marilyn C. Cornelis, an assistant professor in preventive medicine at the Northwestern University Feinberg School of Medicine and co-author of the JAMA Internal Medicine study. Boiled coffee has cafestol and kahweol, compounds called diterpenes. They are shown to raise LDL, the bad cholesterol, and slightly lower HDL, what’s known as the good kind.

Coffee affects all of us differently. Some of us have a polymorphism, a genetic variant that slows our metabolism for caffeine. It’s these individuals that Dr. Grosso recommends limit their refills. “They take a coffee, and then they have the second and the third, and they still have the caffeine of the first,” he said.

Coffee has also been shown to have addictive properties. Evidence suggests there can be a reliance on the drink, and tolerance builds over time. Withdrawal symptoms include a headache, fatigue, irritability, difficulty concentrating, and depressed mood. Caffeine is a psychoactive drug, and coffee is its biggest dietary source.

For those knocking back more than 400 milligrams of caffeine a day, there’s not enough evidence to assess the safety, according to the Dietary Guidelines. Higher doses can lead to caffeine intoxication, with its shakiness, nervousness, and irregular heartbeat. Caffeine is also linked with delaying the time it takes for you fall asleep, how long you stay there, and the reported quality of that shut eye.

Caffeine is something that is part of our culture, so it can be hard to realize that it is the cause of certain problems. Cutting down coffee may help with gastroesophageal reflux, too.

Extremely high doses of caffeine can be fatal. But researchers say that’s more likely to occur accidentally with caffeine powder or pills. “You don’t see a lot of people going into the emergency room because t

With coffee rising in popularity, there is also the concern of specialty drinks becoming more and more available, which are often times filled with sugar and saturated fats. It’s important to be aware of what is going into the drink you are consuming.

Information gathered from The New York Times.