in the reviews his audio book on caffeine with Terry Gross on NPR Last winter, Michael Pollan called caffeine “the enemy of good sleep” because it interferes with deep sleep. He confessed that after the demanding task of weaning himself off of coffee, he “slept like a teenager again”.
Dr. Willett, now 75, said “You don’t have to go to zero to minimize the effects on sleep,” but acknowledged that a person’s sensitivity to caffeine “likely increases with age”. People also vary greatly in the rate at which they metabolize caffeine, so some can sleep soundly after drinking caffeinated coffee for dinner, while others have trouble falling asleep over coffee with lunch. But even if you can easily fall asleep after an evening of coffee, it can affect your ability to get a deep enough sleep, says Mr. Pollan in his upcoming book, This Is Your Mind on Plants.
Dr. Willett said it was possible to develop some tolerance for the effects of caffeine on sleep. My 75-year-old brother, a die-hard coffee drinker, claims it has no effect on him. However, acquiring a caffeine tolerance could diminish the benefits if, for example, you want it to help you stay alert and focused while driving a car or taking a test.
Caffeine is one of over a thousand chemicals in coffee, not all of which are beneficial. Polyphenols and antioxidants, among other things, have positive effects. Polyphenols can inhibit the growth of cancer cells and lower the risk of type 2 diabetes; Antioxidants, which are anti-inflammatory, can counteract both heart disease and cancer, the country’s leading killers.
None of this means that coffee is beneficial regardless of how it is made. When brewed without a paper filter, such as a French press, Norwegian brewed coffee, espresso, or Turkish coffee, oily chemicals called diterpenes leak through, which can increase arterial-damaging LDL cholesterol. However, these chemicals are virtually non-existent in both filtered and instant coffee. Knowing that I had a cholesterol problem, I dissected a coffee capsule and found a paper filter lining the plastic cup. Angry!
Also counteracting the potential health benefits of coffee are popular additives that some people use, such as cream and sweet syrups, which can turn this calorie-free drink into a high-calorie dessert. “All of the things people put into coffee can result in a junk food of up to 500 to 600 calories,” said Dr. Willett. One 16-ounce Starbucks Mocha FrappuccinoEg has 51 grams of sugar, 15 grams of fat (10 of which are saturated) and 370 calories.
As the iced coffee season approaches, more people are likely to turn to cold brew coffee. Now increasingly popular, Cold Brew counteracts the natural acidity of coffee and the bitterness that develops when boiling water is poured over the coffee grounds. Cold Brew is made by soak the soil in cold water for several hours, then strain the liquid through a paper filter to remove the soil and harmful diterpenes and enjoy the taste and caffeine for you. Cold brew can also be made with decaffeinated coffee.
Decaf isn’t entirely devoid of health benefits. As with caffeinated coffee, the polyphenols in it have anti-inflammatory properties that can lower the risk of type 2 diabetes and cancer.