Ensure is an American brand of nutritional supplements and meal replacements manufactured by Abbott Laboratories.

[3] In the 1990s, Ensure and other nutritional drink products like Mead Johnson's Sustacal and Nestlé's Boost and Resource brands were fiercely competing to capture market share among healthy adults.

[4] In 1996, Ensure had sales of about $300 million and accounted for 80% of protein supplement sales; Abbott spent $45.4 million to advertise Ensure during the first nine months of 1996, around 70% more than it spent during the same period of 1995.

[4] In 1997, Abbott settled charges from the Federal Trade Commission that it was falsely marketing Ensure as having similar amounts of vitamins as multivitamin supplements, and as recommended by doctors more than any other nutritional supplement as a way for people to stay active and healthy.

[4][6] Ensure has been used in the force feeding of hunger-striking prisoners at the United States' Guantanamo Bay detention camps.