Coffee, Tea, and Chocolate are all heavily used food substances.  They have been heavily studied for years due to concerns that they cause disease.  Indeed, Sanka, the first caffeine-free coffee, was invented by a German who was convinced that his father had been killed by a coffee induced heart attack.  Fortunately, it does not appear that caffeine has overall harmful health effects.  

It is likely that caffeine does make some individuals, especially those with panic disorders, more anxious.  Caffeine may also cause a significant amount of insomnia and headaches.  However, coffee, except for very heavy drinkers, does not increase heart attacks or shorten life.  It does lower suicide rates and the risk of developing Parkinson's disease.

Intake, Tolerance, Withdrawal in Twins: Individual differences are substantially influenced by genetic factors in this study of 486 monozygotic and 335 dizygotic twin pairs. Estimated heritability ranged 35% to 77% with family environment contributing little. Ken Kendler, Am J Psychiatry 2/99, 156:223-8.  

Meat Bad; Nuts, Whole-Grains, Fruit, Vegetables, Legumes Good: Most Seventh-day Adventists do not smoke cigarettes or drink alcohol. In a study of 34,192 California Seventh-day Adventists, about 50% ate meat <1 time/wk or not at all. These vegetarians consumed more tomatoes, legumes, nuts, and fruit, but less coffee, doughnuts, and eggs. Multivariate analyses showed significant associations between beef 3+ times/week vs. <1 and fatal ischemic heart disease (IHD) with an RR = 2.31, RR = 0.5 for nuts at 5+ times/wk vs. <1 time/wk), and reduced risk of IHD for whole-grain to white bread. The lifetime risk of IHD was reduced by 31% for frequent nuts and by 37% in vegetarians. Cancers of the colon and prostate were significantly more likely in nonvegetarians (RR of 1.88 and 1.54), and frequent beef consumers also had higher risk of bladder cancer. Intake of legumes was negatively associated with risk of colon cancer in nonvegetarians and risk of pancreatic cancer. Higher consumption of all fruit or dried fruit was associated with lower risks of lung, prostate, and pancreatic cancers. Cross-sectional data suggest vegetarian Seventh-day Adventists have lower risks of diabetes mellitus, hypertension, and arthritis than nonvegetarians. Associations between diet and cancer, ischemic heart disease, and all-cause mortality in non-Hispanic white California Seventh-day Adventists. Fraser GE. Loma Linda University. Am J Clin Nutr. 1999  Sep;70(3 Suppl):532S-538S

Caffeine Good Against Slugs, Snails: 1-2% solution kills or repels. Better than commercial products. Instant 0.05% in usual cup, therefore, make it 20 times stronger. Nature 6/27/02.

Adenosine Receptors Involved in Caffeine Anxiety & Panic Disorder: Adenosine A1 receptors found throughout the brain. A2a in basal ganglia. Caffeine stimulates both. DB study U Chicago and Germany 94 normal adults. Those with two variants of A2a had anxiety responses to caffeine. Panic disorder patients have same variants. 12/10/02. Dec. 8 at the annual meeting of the American College of Neuropsychopharmacology held in San Juan, Puerto Rico

Thomas E. Radecki, M.D., J.D.

modern-psychiatry.com