Less-than-optimal diets caused more than four million deaths from ischaemic heart disease worldwide in 2023, according to a new study published in Nature Medicine.
Researchers from Massachusetts General Hospital and Kyung Hee University analysed data from the Global Burden of Disease Study covering 204 countries and territories.
The study found that sub-optimal diets were responsible for 4.06 million deaths from ischaemic heart disease, also known as coronary artery disease, in 2023. The condition occurs when plaque builds up in the coronary arteries, reducing blood flow to the heart.
Researchers said the number of global diet-related ischaemic heart disease deaths rose 41.59 per cent compared with 1990.
However, the age-standardised death rate linked to dietary risks fell by nearly 44 per cent over the same period, from 80.62 deaths per 100,000 people in 1990 to 45.22 per 100,000 in 2023. The authors said this suggested improvements in healthcare and living conditions despite population growth.
The study identified low intake of nuts and seeds, whole grains, and fruits, along with high sodium consumption, as the leading dietary factors behind these deaths. Low intake of nuts and seeds was linked to 9.87 deaths per 100,000 people, followed by low whole grain intake at 9.22, low fruit intake at 7.25, and high sodium intake at 7.15.
The burden was greatest in countries with low and middle sociodemographic status, where people consumed too few protective foods. In wealthier countries, researchers found a higher burden linked to excessive intake of processed meat and sugary drinks.
People aged 65 and older had much higher death rates than those aged 45 and under.
The study also found that the burden of diet-related heart disease declined in most parts of the world, except in Southeast Asia, Sub-Saharan Africa, Oceania, and South Asia.