Iced Tea: Just as Healthy as Hot?
The answer: It depends
Nothing says summer like a tall glass of iced tea, ideally sipped while your feet are propped up on the poolside chaise or you’re in the backyard hammock. In 2014, Americans drank more than 80 billion servings of tea, according to the Tea Association of the U.S.A., and 85 percent of it was iced.
Ever wondered, though, how iced tea stacks up against old-fashioned brewed hot tea? We asked the experts to steep us in knowledge.
Overall health benefits of tea
Experts are discovering more and more health benefits of tea, says Qi Sun, MD, ScD, assistant professor of medicine at Harvard School of Public Health and Brigham and Women's Hospital. Sun and his colleagues have followed large groups of doctors and nurses and found that regular tea drinking may:
- lower the risk of cardiovascular disease
- lower the risk of diabetes
- reduce blood pressure
- improve cholesterol levels
The health benefits of tea are mainly due to a type of antioxidant known as polyphenols, Sun says, especially a group of compounds called catechins.
Green tea and white tea have more of these catechins than black tea does, Sun says. The amount also depends on the tea leaves used and how much oxidation is involved in the processing of the leaves, he says. "Catechins make tea special. Black tea has lower levels of these compounds than green or white teas. That doesn't mean black tea is bad. It still has antioxidants, but the levels are lower."
Brewed vs. iced
"If you make your own tea, it wouldn't make a difference'' whether you drink it hot or iced, as far as the antioxidant content goes, Sun says. If the choice is home-brewed iced tea or store bought, he says, choose homemade. Commercial teas generally use fewer tea leaves to make the same amount of tea. "[They] still have catechins, but the levels are lower," he says.
Sun tea: Is it safe?
Brewing tea with cold water in a glass pitcher placed in the sun for four or five hours makes the delicate-tasting summer treat known as sun tea. But is it true that sun tea can harbor dangerous bacteria?
Theoretically, yes. That’s because the sun doesn’t make the water hot enough to kill off any bacteria that might be present, according to Centers for Disease Control and Prevention foodborne disease expert Robert Tauxe, MD, MPH.
Omar Oyarzabal, PhD, associate professor of food safety at the University of Vermont, says "There is little scientific information on the pathogenic bacteria in teas, but we know bacteria can survive and be present in teas." Instead of setting the tea out in the sun, he suggests soaking the tea in cold water in the refrigerator.
Any risk of sun tea is likely small, however. Edward Dudley, PHD, associate professor of food science at Penn State University, says, ''I am not aware of any study [about the dangers of sun tea] and not aware of any outbreaks that have occurred."
If you still want to make sun tea, "be sure to clean the container," says Dudley, who is also head of the food microbiology division for the American Society for Microbiology. Don't use containers with hard to clean parts, such as spigots, he says.
Other tips to keep that sun tea safer, according to Oyarzabal:
- Use glass containers only.
- Use tea in bags bought at a food store.
- Cover the container after adding the tea.
- Leave the tea out no more than four hours; two is actually enough.
- Refrigerate the tea as soon as you bring it inside. If the container is a gallon or more, first divide it into smaller containers so the tea cools faster.
- Drink the tea within two days.
- If anything funky is in the tea (foam, sediments, ropey strands), throw it out.
Sweeteners: The real deal breaker
Skip the sugar if you want to keep tea the healthy beverage it can be. If you use a commercial iced tea mix or prepared tea that is sweetened, ''you are going to lose the benefit of drinking tea," Sun says. "All the benefits of the teas are offset by the added sugar." That added sugar is linked with weight gain, among other problems, he says.
Many varieties of unsweetened teas are on the market, including tea pods you can brew and ice at home, unsweetened tea mixes and bottles of unsweetened tea.