Cardiovascular disease is the leading cause of death worldwide, accounting for more than 17.3 million deaths per year — a number that is expected to grow to more than 23.6 million by 2030. In the United States, heart disease kills more than 370,000 people a year, striking someone about once every 42 seconds.

But new research indicates that a Mediterranean diet that limits meat and boosts the intake of plant-based foods, like fruits and vegetables, may be beneficial for the heart — especially for older adults.

Studies show the risk of heart failure appears high within a few years of a first heart attack. In one study, researchers analyzed data from nearly 25,000 people in the United Kingdom who suffered a first heart attack. Nearly 25 percent of these patients developed heart failure within four years.

In aging populations, heart failure is also the leading cause of mortality. Although the total population increased by 9.7 percent between 2000 and 2010, those over 65 years of age increased by 15 percent. Furthermore, the greatest proportional increases over this 10-year period occurred in the oldest age groups, with a 30 percent increase in those 85 to 94 years of age and a 25 percent increase in those over 95 years of age.

This increase in the aging population has implications for heart failure. As of 2012, an estimated 2.4 percent of the U.S. population had heart failure, with prevalence increasing with age. Among those 80 years and older, approximately 12 percent of both men and women had heart failure.

The mechanism of inflammation in heart attack and stroke remains a topic of investigation. What researchers do know is that after tissue injury during a heart attack, the body has an early acute inflammation response that removes dead cells and repairs the injured area, with lipids known as resolvins signaling the healing process.

However, in contrast to healthy healing, age and increased omega-6 fatty acid may promote or increase heart inflammation. A healthy diet contains a balance of omega-3 and omega-6 fatty acids. The typical Western diet is higher in the ratio of omega-6 fatty acids to omega-3 fatty acids. In fact, the typical American diet tends to contain 14 to 25 times more omega-6 fatty acids than omega-3 fatty acids.

According to a 2002 World Health Organization report, a diet poor in fruits and vegetables is the third preventable risk factor for chronic diseases, which have replaced infectious disease as the leading cause of morbidity and mortality in the world. The same report showed that among the 20 countries with the highest life expectancy in the world, four of them are Mediterranean countries, such as France, Spain, Greece and Italy.

In a recent study, researchers found that a combination of age and excess omega-6 fatty acid led to increased heart inflammation compared with a lower-fat diet. Researchers at the University of Alabama at Birmingham, led by Ganesh Halade, Ph.D., assistant professor in the Division of Cardiovascular Medicine, conducted experiments in mice to demonstrate how aging and excess dietary fat create signals that lead to heart failure after a heart attack.

Young and aging mice were fed standard lab chow and excess fatty acid-enriched diet for two months and then myocardial infarction. The researchers discovered lower amounts of three types of lipoxygenase enzymes in the dead area of the heart muscle, lower amounts of resolvins that help resolve acute inflammation, increased amounts of pro-inflammatory macrophage immune cells, and finally, increased kidney injury as well as tumor necrosis factor-alpha and interleukin-1 beta, which are two signaling cytokines that promote inflammation.

This study demonstrates that excess fatty acid intake magnifies post-myocardial signaling that may lead to heart failure after a heart attack. The Mediterranean diet discourages eating meat and encourages eating plant-based foods, such as fruits and vegetables, whole grains, legumes and nuts. The diet replaces butter with healthy fats, such as olive oil and canola oil, and uses herbs and spices instead of salt.

All of which leads to a much lower ratio of omega-6 to omega-3 fatty acids and may be beneficial, especially in older people who have suffered a heart attack.