There might be another reason to be worried about your coffee and soda addiction.
An international group of researchers, including one out of McMaster University, has linked high intake of soda and juice to an increased risk of stroke.
The study, published on Sept. 27 in the Journal of Stroke, found that the chance of stroke increased for people who drank soda and fruit juice once or more per day, while coffee drinkers who consumed more than four cups a day also had an increased risk of stroke. It follows several other recent studies that have linked ingredients in some sodas and soft drinks, like artificial sugars, to increased stroke, heart attack and blood clot risk.
While the study established a connection between soda, juice and coffee consumption and stroke, it didn’t establish that those beverages cause strokes, something additional research could prove or disprove.
What drinks were linked to stroke risk?
The study analyzed worldwide data from Interstroke — a survey of risk factors for stroke involving nearly 27,000 people from 27 countries, half of whom had experienced their first stroke.
People who drank soda or juice more than once per day or coffee-drinkers who consumed more than four cups a day had an increased chance of stroke, according to Andrew Smyth, a researcher with the University of Galway and McMaster University.
Those who drank carbonated beverages, both sugar-sweetened and diet beverages were associated with all strokes — including ischemic stroke, when a blood clot blocks an artery leading to the brain, and an intracerebral hemorrhage, also known as brain bleed. While high juice intake was linked to just intracerebral hemorrhage and not ischemic stroke.
What should you drink instead?
On the flip side, though, the results found that drinking tea, especially green and black tea drinkers who consumed more than three to four cups per day had a reduced risk of stroke, and the same went for those who had a high water intake (nearly two litres per day) for older adults.
While there’s no definitive research that shows soda and juice consumption lead to strokes, “we know diet is an important risk factor for cardiovascular disease and stroke,” Elise Pauzé, a policy analyst with the Heart and Stroke Foundation of Canada who wasn’t involved with the study, said.
Sodas, fruit juices and other sugary drinks have “been linked with stroke, heart disease, diabetes, high blood cholesterol and obesity,” Pauzé added.
Smyth recommends people reduce or minimize their intake of sodas and fruit juice, and should opt for water “as much as possible.”
Just one in three Canadians met the World Health Organization’s recommended sugar intake levels in 2015, a Statistics Canada study estimated, mainly due to sweets and beverages.
If all Canadians complied with the WHO recommendations in 2019, we could have saved $2.5 billion in direct and indirect health-care costs through chronic disease prevention, another study published in the Canadian Journal of Public Health found. It’s why researchers and advocates have lobbied the government for a “sugar tax” to help curb excess sugar consumption — and though a 20 cent per litre soda tax hit Newfoundland and Labrador in 2022, the rest of the country has yet to follow suit.
The study’s limitations
The study took its data from the observational Interstroke survey — meaning people were recruited and asked about their recent intake of coffee, sodas and juice, and not tested in a clinical setting.
There’s also a myriad of factors that could affect the results of the study, Smyth said. There was only one question on coffee intake, and the researchers involved didn’t look into whether participants consumed caffeinated or decaffeinated coffee, used sugar or sweeteners, added dairy or non-dairy milks, or how they brewed their coffee. The same goes for sodas and juice, where Smyth and his fellow researchers didn’t separate out sugar-sweetened, artificially sweetened, diet and zero sugar drinks, and instead lumped them all together.
Pauzé also noted that findings were not consistent across all regions, and could be attributed to regional differences in food supplies.