Coffee Reconsidered: New Grounds for Drinking It

Moderation moderates cardiovascular risk. A recent study examined whether the CYP1A2 genotype or a genetic score for caffeine metabolism (caffeine-GS) modifies the association between habitual coffee consumption and CVD risk. A nonlinear association was found between habitual coffee intake (≥6 cups/d) and CVD risk. Compared to those who drank 1 or 2 cups of coffee daily, habitual coffee drinkers had a 22% increased risk of CVD, followed by 11% for nondrinkers and 7% for drinkers of decaffeinated coffee; CYP1A2 genotype and caffeine-GS were not associated with CVD. The study was published in the American Journal of Clinical Nutrition in March.

Caffeine is not the culprit. A recent investigation published August 6 in the journal Sleep determined that, contrary to popular belief, evening caffeine consumption is not associated with increased sleep fragmentation that night. Researchers recorded consumption of alcohol, nicotine, and caffeine within 4 hours of bedtime in a large cohort of black patients who participated in the Jackson Heart Sleep Study. Evening caffeine use was not associated with sleep duration, sleep efficiency, or wake after sleep onset. Evening nicotine use was associated with increased sleep fragmentation and nicotine and alcohol intake was associated with lower sleep efficiency, even after controlling for potential confounders.

Coffee trumps sugar. Substituting coffee or tea for SSBs may help prevent T2DM. In the European Prospective Investigation into Cancer and Nutrition (EPIC)–InterAct case–cohort study, substituting coffee for SSBs by 250 g/d resulted in a 21% lower incidence of T2DM (rate difference, −12.0 per 10 000 person-years); tea substituted for SSBs lowered T2DM incidence by 22% (rate difference, −11.0 per 10 000 person-years). Neither fruit juice nor milk significantly altered T2DM risk. The research was published August 8 in The Journal of Nutrition.

Caffeine giveth and taketh away. A prospective cohort study of 98 adults with episodic migraine, mostly women, found a nonlinear association between caffeinated beverage intake and the odds of migraine occurrence, suggesting that high levels of caffeinated beverage intake may be a trigger of migraine on that day. First the bad news: Drinking ≥3 servings of caffeinated drinks a day was associated with the onset of a migraine attack on that day or the next. But the good news is that 1 or 2 servings/d was not associated with migraine risk. The study was published online on August 2 in the American Journal of Medicine.

Coffee and cancer not linked. Previous studies have suggested a reduction in cancer risk with coffee intake, but in a study of 46 155 cases from the UK Biobank cohort, coffee consumption was not associated with overall risk of receiving a diagnosis of or dying from cancer. A small effect on specific types of cancer could not be ruled out, but a strong causal relationship between coffee and risk of breast, ovarian, lung, or prostate cancer was not supported. The study appeared on July 17 in the International Journal of Epidemiology.

The liver likes coffee. Coffee intake probably reduces the risk of liver cancer and may lower the risk of CLD, according to a recent literature review. Most observational studies and meta-analyses show coffee having a protective effect on liver cancer risk, the authors noted. Potential mechanisms of CLD risk reduction include the effect of bioactive compounds (eg, caffeine, chlorogenic acids, phenolic compounds, diterpene); antioxidant properties; induction of defense mechanisms; and anti-inflammatory properties. The review was first published online on April 11 in Current Nutrition Reports.