Ireland ranks 35th in a league table showing countries in Europe and central Asia with diet-related heart disease deaths.
Researchers examined how many heart disease deaths could be attributed to a diet high in salt but low in vegetables, nuts and whole grains.
Ireland has 79 diet-related heart disease deaths per 100,000 people, equivalent to 4,984 deaths annually.
The league table analyses 51 nations and found the worst was Uzbekistan in the number one spot. The best nations were Spain and Israel.
Figures from the Global Burden of Disease Study showed 2.1 million people died because of heart disease caused by what they eat.
In the worst countries nine times more people are dying because of their food than in countries which are least affected.
Western European nations manage to stay clear of the top half of the table, which is made up primarily of Asian and Eastern European countries
Germany is the worst performing in Western Europe and the only one in the region to have more than 100,000 people die in 2016 because of their diet.
Professor Stefan Lorkowski the study author said: "We must make better use of the potential of a balanced and healthy diet, otherwise [heart] diseases will be the cause of even more preventable deaths in the future."
Professor Lorkowski, from Friedrich Schiller University Jena in Germany, said the figures were "crucially relevant".
The figures relate to 1990 and 2016. The scientists said that in much of central and eastern Europe, along with central Asian countries, a lack of whole grains is most concerning.
He said: "To put it another way: increased consumption of low-fibre white flour products has led to an increase in heart disease in recent years."
The research examined how people's diet affects other risk factors for heart disease, including obesity, high blood pressure and lack of exercise. It did not include alcohol consumption.
Other countries with good heart-related diets are France, Netherlands, Andorra, Denmark, Belgium, Switzerland, Norway and Italy.
Women's diets are better than men's.
The timing is perfect. As thousands of people may be about to fall off the wagon of their new year diet and detox regime in comes the chilling figures showing more of us are sliding into overweight and obesity.