The first five ingredients in an Ensure meal replacement shake are water, sugar, corn syrup, corn maltodextrin and milk protein concentrate. Ensure also contains a number of added vitamins and minerals such as zinc sulfate, niacinamide, magnesium sulfate and calcium pantothenate.
The primary ingredients in Ensure shakes are water and sugar. For this reason, critiques of Ensure from Diet Spotlight and Natural News indicate that the product may not be a particularly healthy meal replacement choice. Corn syrup and corn maltodextrin are both used as sweeteners in a variety of food products.
Other ingredients in Ensure shakes include soy oil, cocoa powder, soy protein concentrate, canola oil and corn oil. The cocoa powder may or may not be present depending on the flavor of the beverage. Ensure shakes come in six flavors as of 2015, all of which are derived from a combination of natural and artificial flavorings.
Ensure meal replacement shakes contain roughly 25 percent of a person's required daily intake of nutrients such as thiamin, riboflavin, niacin, vitamin B6 and folate. They also contain 50 percent of the required daily intake of vitamin C and vitamin D. Other varieties of Ensure shakes contain slightly different ingredients and nutritional values. For example, Ensure Active High Protein contains 16 grams of protein per serving, as compared to 11 grams in the original formula.