Bottled, flavored, or carbonated waters are other options that cost more but offer the same benefits as tap water (except, possibly, fluoridation) and may be preferable to some people. An inexpensive way to flavor water at home is to brew some caffeine-free herbal iced tea.
Plain tea contains no calories or carbohydrate, meaning it is a “free food” in a diabetes meal plan. When sugar, honey, or milk is added, however, a cup of tea can have enough carbohydrate to require its being counted as a carbohydrate-containing food.
Tea is believed to have various health benefits, largely because of the naturally occurring antioxidants called flavonoids in tea. Some studies have suggested that regular tea consumption may reduce the risk of developing Type 2 diabetes, protect against coronary heart disease, and improve bone and dental health. So far, however, the FDA has rejected the petitions of distributors of green tea to print health claims on tea package labels, saying there is insufficient evidence to claim that tea can help prevent heart disease or cancer.
Tea contains caffeine, which, in moderate amounts does not appear to affect blood glucose levels. However, some research suggests that consuming 500 milligrams (mg) of caffeine over a short period has the potential to raise blood glucose levels. Such large doses of caffeine enhance the effects of the hormones epinephrine and glucagon, which stimulate the release of glucose from the liver.
Luckily, it would be difficult to get that much caffeine from drinking tea. A cup of brewed black tea contains about 40 mg of caffeine, a cup of brewed oolong tea contains about 30 mg of caffeine, and a cup of green tea contains about 20 mg of caffeine. White tea, which is rarer and more expensive than the other types, contains about 15 mg of caffeine per brewed cup.
Even if it doesn’t raise blood glucose levels, caffeine can increase heart rate, a symptom that may be mistaken as a sign of low blood glucose. If you experience what feels like symptoms of low blood glucose after drinking tea or other caffeinated beverages, check your blood glucose level with your meter to see what effect if any caffeine has on it.
Like plain tea, black coffee contains no calories or carbohydrate and is a free food in a diabetes meal plan. However, many people add milk or soy milk to their coffee, in which case their coffee drink would count toward both their coffee and milk totals in the Beverage Guidance System. One-quarter cup of skim milk adds about 23 calories and 4 grams of carbohydrate, 1/4 cup of low-fat (1%) milk adds about 26 calories and 3 grams of carbohydrate, and 1/4 cup of unsweetened soy milk adds about 23 calories and 1 gram of carbohydrate.
One cup (8 ounces) of brewed coffee generally contains between 85 and 135 mg of caffeine. A serving of espresso, which is 1–2 ounces, contains about 100 mg of caffeine. Drinks that contain several “shots” of espresso, therefore, can contain quite a bit of caffeine.
Powdered dessert coffees sold at grocery stores come in many flavors in both regular and sugar-free varieties. Varieties sweetened with sugar provide 11–20 grams of carbohydrate (1 carbohydrate choice) per serving. Sugar-free varieties contain about 5 grams of carbohydrate per serving, making a single serving of this coffee a free food.
When you prepare coffee at home, it’s easy to figure out how many calories and grams of carbohydrate and fat you’re consuming. When you purchase coffee drinks in a coffee shop such as Starbucks or Dunkin’ Donuts, it can be more difficult, since the nutrition information may not be posted next to the menu, and some menu terms may be unfamiliar. However, many restaurant chains now post nutrition information on their Web sites, so you can plan your purchases in advance by looking online.