A study led by McMaster University and Hamilton Health Sciences researchers at the Population Research Health Institute (PHRI) has found that not eating enough of six key foods in combination is associated with a higher risk of cardiovascular disease (CVD) in adults.

Consuming fruits, vegetables, legumes, nuts, fish and whole-fat dairy products is key to lowering the risk of CVD, including heart attacks and strokes. The study also found that a healthy diet can be achieved in various ways, such as including moderate amounts of whole grains or unprocessed meats.

Previous and similar research has focused on Western countries and diets that combined harmful, ultra-processed foods with nutrient-dense foods. This research was global in scope and focused on foods commonly considered to be healthy.

The World Health Organization estimates nearly 18 million people died from CVD in 2019, representing 32 per cent of all global deaths. Of these deaths, 85 per cent were due to heart attacks and strokes. PHRI researchers and their global collaborators analyzed data from 245,000 people in 80 countries from multiple studies. The results were published in the European Heart Journal on July 6.

Researchers derived a diet score from PHRI’s ongoing, large-scale global Prospective Urban and Rural Epidemiological (PURE) study, then replicated that in five independent studies to measure health outcomes in different world regions and in people with and without prior CVD.

“Previous diet scores – including the EAT-Lancet Planetary Diet and the Mediterranean Diet tested the relationship of diet to CVD and death mainly in Western countries. The PURE Healthy Diet Score included a good representation of high, middle, and low-income countries,” said Salim Yusuf, senior author and principal investigator of PURE.

As well as being truly global, the PURE Healthy Diet Score focused on exclusively protective, or natural, foods.

“We were unique in that focus. The other diet scores combined foods considered to be harmful – such as processed and ultra-processed foods – with foods and nutrients believed to be protective of one’s health,” said first author Andrew Mente, PHRI scientist and assistant professor at McMaster’s Department of Health Research Methods, Evidence, and Impact.

“There is a recent increased focus on higher consumption of protective foods for disease prevention. Outside of larger amounts of fruits, vegetables, nuts and legumes, the researchers showed that moderation is key in the consumption of natural foods,” he said.

“Moderate amounts of fish and whole-fat dairy are associated with a lower risk of CVD and mortality. The same health outcomes can be achieved with moderate consumption of grains and meats – as long as they are unrefined whole grains and unprocessed meats.”

The PURE Healthy Diet Score recommends an average daily intake of: Fruits at two to three servings; vegetables at two to three servings; nuts at one serving; and dairy at two servings. The score also includes three to four weekly servings of legumes and two to three weekly servings of fish. Possible substitutes included whole grains at one serving daily, and unprocessed red meat or poultry at one serving daily.

There was no specific funding for this analysis, although each study that contributed data was funded separately and conducted over a 25-year period.