Glucerna cereals are a source of whole grains. A 3/4-cup serving of the Crunchy Flakes ‘n Raisins variety contains 110 calories, 28 grams of carbohydrate, and 5 grams of fiber.
Glucerna shakes are sold in 8-ounce, reclosable, plastic bottles, while Snack Shakes are sold in 8-ounce metal cans. The shakes provide 200 calories, 26–27 grams of carbohydrate, and 5 grams of fiber per serving. The snack shakes provide 140 calories, 19 grams of carbohydrate, and 3 grams of fiber per 8-ounce serving.
Another component of energy bars and shakes that may help with blood glucose control is protein. Protein does not directly raise blood glucose level the way carbohydrate does, but it does cause the pancreas to release insulin when consumed with carbohydrate (in people with functioning pancreases). Protein also tends to have a satiating, or satisfying, effect, so you may feel fuller after a high-protein meal.
One product that boasts a high protein content and is marketed specifically to people with Type 2 diabetes is Boost Glucose Control, a nutrition shake made by Nestlé Healthcare Nutrition, Inc. The shake also contains a variety of slowly absorbed carbohydrates — namely tapioca dextrin (a breakdown product of tapioca starch), inulin (a type of soluble plant fiber), and guar gum (a type of carbohydrate derived from beans).
According to the manufacturer, a study conducted by Nestlé researchers in people with Type 2 diabetes showed that drinking Boost Glucose Control resulted in a blood glucose peak below 180 mg/dl, which is within the after-meal range recommended by the American Diabetes Association.
Boost Glucose Control shakes are sold in 8-ounce, reclosable, plastic bottles and are intended to be used as a snack or small meal. Each single-serving container provides 190 calories, 16 grams of carbohydrate, 16 grams of protein, and 3 grams of fiber.
Fat tends to slow the digestion of carbohydrate and therefore to slow the rise in blood glucose level after eating a snack or meal that contains both. This is one of the reasons the makers of nutrition bars and shakes include some fat in their products. Another is that certain fats — in particular, monounsaturated fats, polyunsaturated fats, and a type of polyunsaturated fat called omega-3 fatty acids — appear to be beneficial to heart health, so products that contain them generally mention that fact prominently in their marketing materials.
Enterex Glucose Control, for example, which markets itself as a “nutritionally balanced snack drink,” notes that it contains only oils high in monounsaturated fat such as canola oil (which also contains omega-3 fatty acids) and high-oleic safflower oil. An 8-ounce can of Enterex Glucose Control provides 237 calories, 9 grams of fat, 27 grams of carbohydrate, and 3 grams of fiber.
Vitamins and minerals
Some bars and shakes marketed to people with diabetes contain multiple vitamins and minerals, and some carry label claims suggesting that certain vitamins and minerals can help to control diabetes or its complications. At this time, there is no evidence that specific vitamins or minerals improve blood glucose control, although research is ongoing on this subject.
However, there is the risk of getting too much of some vitamins and minerals if several bars or shakes containing large amounts of vitamins and minerals are consumed during the day or if a multivitamin is taken in addition to a bar or shake containing high amounts of vitamins and minerals. If you are already getting 100% of the recommended dietary allowance of most vitamins and minerals from a multivitamin, you do not need another 100% from a nutrition bar or shake.