If you are going to have a vice, coffee is probably one of the least harmful as long as you drink it in moderation, according to the July issue of Mayo Clinic Health Letter. Caffeine is the kick in your coffee and drinking too much of it can have noticeable effects. But, as for coffee causing serious health problems, so far the research hasn't proven any links. Research on coffee s effects continues. Compounds in coffee have been linked to increased cholesterol levels, but the compounds aren't found in filtered or instant coffee, which most Americans drink.
Caffeine can intensify certain heart rhythm problems.
It can also cause a temporary rise in blood pressure. Caffeine increases the amount of calcium excreted in your urine. This suggests that coffee may increase your risk for osteoporosis, but you'd have to drink large amounts of caffeine every day to have any noticeable impact on bone density. Evidence that coffee can lead to fibrocystic breast changes, in which benign but painful lumps develop in your breast, appears to be weakening. However, caffeine may aggravate the condition.