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food for thought

Plenty of evidence suggests that daily coffee drinking helps stave off numerous health issues, including Type 2 diabetes, heart disease, gallstones, Parkinson’s disease and liver cancer, as well as early death.

So far, though, research hasn’t discerned between black coffee and sweetened coffee. Which raises the question: Does adding sugar to coffee undo its potential health benefits?

Now, a new study has investigated this query. Hint: if you take your coffee with a teaspoon of sugar, you’ll be pleased with the findings. Here’s what to know.

The latest research

The study, published May 31 in the Annals of Internal Medicine, looked at the association between unsweetened (black), sugar-sweetened and artificially-sweetened coffee and mortality risk among 171,616 adults living in the United Kingdom. Participants, ages 37 to 73 (average age 56), had no history of heart attack, stroke or cancer and were followed for seven years.

At the outset of the study, participants completed a dietary questionnaire to provide detailed information about coffee consumption and food intake. The researchers assessed daily intake of calories, sugar, red and processed meats, fruits and vegetables as well as alcohol intake and the use of vitamin supplements.

The findings: Compared to non-coffee drinkers, people who drank moderate amounts of either unsweetened or sweetened coffee had up to a 30 per cent lower risk of premature death from any cause. Participants who drank sweetened coffee added only one teaspoon of sugar to each cup.

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Among black coffee drinkers, those who drank three cups a day had the lowest mortality risk. For sugar-sweetened coffee drinkers, having two cups a day was tied to the lowest mortality risk. One cup of coffee was defined as 250 ml or eight ounces.

Drinking a moderate amount of black coffee was also associated with a lower risk of dying from cardiovascular disease and cancer during the study period.

These associations were consistent for ground, instant and decaffeinated coffee.

To arrive at their conclusions, the researchers accounted for participants’ diets as well as other factors such as education level, smoking status, physical activity, body mass index, waist circumference, hypertension, diabetes, family history of cardiovascular disease or cancer and medication use.

The link between artificially-sweetened coffee and risk of dying was less consistent and inconclusive.

Strengths, drawbacks

This study has several strong points, including its large sample size and detailed coffee information that included types of coffee not typically examined in other studies. The researchers also accounted for extensive dietary, lifestyle and medical factors that could have influenced the findings.

A limitation of the study is that coffee consumption data was collected only at the start of the study so it didn’t capture changes over time. It’s possible that some people switched from sweetened coffee to black coffee, or vice versa, during the study.

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As well, the study’s observational design can’t prove that drinking unsweetened or sugar-sweetened coffee is directly responsible for preventing early death.

Even so, coffee contains several bioactive compounds that make its health benefits conceivable.

Coffee’s protective ingredients

Caffeine and chlorogenic acid, a phytochemical in coffee, have antioxidant and anti-inflammatory effects in the body. Coffee extracts have also been shown to inhibit blood platelets from clumping together, suggesting that drinking coffee could reduce the risk of blood clots that cause heart attack and stroke.

Coffee compounds called diterpenes are thought to have anti-cancer effects. Coffee also contains magnesium, a mineral that helps the body secrete and use insulin properly.

Bottom line

If you drink your coffee black or add only a little sugar, these new findings may be reassuring. Drinking either type may help you live longer.

What this study doesn’t answer, of course, is if drinking sugar- and fat-laden coffee (e.g., Frappuccino, Caramel Macchiato, Tim Horton’s Double Double) is still potentially beneficial or at least not harmful.

Considering, though, that a large Tim Horton’s Double Double has 24 g of added sugar (6 teaspoons worth), not to mention 10 g of saturated fat, I can’t possibly imagine that a daily intake of these sweet coffee beverages is good for you.

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Keep in mind, too, that the health benefits associated with black or lightly sweetened coffee are seen with moderate intakes. The risk of harmful effects increases with heavy coffee intakes.

My advice: keep your coffee simple and your intake moderate. Enjoy it black or with a splash of milk. If you must sweeten it, stick to no more than one teaspoon of sugar.

Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD

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