Study: Chocolate consumption and incidence of heart failure

reference

Mostofsky E, Levitan EB, Wolk A, Mittleman MA. Chocolate consumption and incidence of heart failure: a population-based prospective study of middle-aged and elderly women.Heart failure. 2010;3(5):612-616.

design

Prospective cohort study

Participant

31,823 women aged 48 to 83 years who participated in the Swedish mammography cohort

Studying “Medicines”

Chocolate. The frequency of chocolate consumption was compared to the frequency of heart failure. The women were followed from January 1, 1998 to December 31, 2006 for heart failure (HF), hospitalization, or death. During this period, 419 women were hospitalized for heart failure (n=379) or died of heart failure (n=40).

Key findings

Women who consumed 1 to 3 servings of chocolate per month had a 26% lower risk of heart failure compared to women who did not regularly consume chocolate. For those who consumed 1 to 2 servings per week, the risk fell by 32%. The risk may increase with higher consumption, but the numbers did not reach statistical significance.¹

Effects on practice

Moderate consumption of chocolate (1-2 servings/week) could reduce the risk of heart failure in women, a finding that few will complain about.

Moderate consumption of chocolate (1 to 2 servings/week) could reduce the risk of heart failure in women, a finding that few will complain about.

A number of recent clinical studies using high polyphenol chocolate suggest that chocolate has a blood pressure lowering effect in hypertensive individuals. A meta-analysis published in June 2010 combined data from 13 studies and concluded that "dark chocolate is superior to placebo in reducing systolic hypertension or diastolic prehypertension."²
What is striking about the Mostofsky study is that no “special” chocolate was required. Plain chocolate, or at least the chocolate commonly consumed in Sweden, was enough to provide a significant benefit. That's not to say that special high-polyphenol chocolates can't provide even greater benefits.

On this topic, the study by Janszky et al. from 2009 can be mentioned. In this previous work, 1,169 Swedish patients were followed after they were hospitalized with a first heart attack. Chocolate consumption as well as hospitalizations and mortality were recorded. Chocolate consumption had a strong inverse association with cardiac mortality. Compared to those of people who never eat chocolate, the risk ratio was 0.73 for those who consumed chocolate less than once a month, 0.56 for up to once a week, and 0.34 for two or more per week. In contrast, consumption of other sweets was not associated with cardiac or all-cause mortality.³

The data now clearly supports our message to patients that weekly chocolate consumption is not only acceptable, but even recommended for people at increased risk of heart failure or myocardial infarction.