They are for people who have lost their appetite and don't want to eat. Yes, it will HELP control blood sugars in diabetics IF YOU USE IT AS DIRECTED to replace a meal and don't just drink it like a milkshake to wash down the pizza and donut you had for lunch.

Stay away from it. Boost is loaded with sugar - it's counterproductive. To control blood sugar you need to do a couple of things toward a better lifestyle. One is to drink more water. Blood is 94% water and when you don't stay properly hydrated the water loss from the blood is around 8%, increasing its viscosity. This thicker blood inhibits insulin from carrying glucose into the cells - this is part of what's referred to as "insulin resistance". Another aspect you need to consider is salt. The medical profession wrongly demonizes salt, encouraging people to avoid it. The problem here is, salt is a vital component for maintaining proper health. It not only retains water in the cells but it's needed for hydrolysis - the production of energy. It also regulates blood sugar. Many people have experienced what's known as the "Dawn Phenomenon" where their morning blood sugar is raised. This happens because of the body's routine maintenance function. The brain is the one organ that doesn't need insulin to function properly. But it does use sugar and because it is the central control unit of the body, it puts its own needs first. When the maintenance program begins, the liver produces extra blood sugar to provide the energy needed. When the brain detects this extra sugar production, it thinks that there will be a shortage - so it instructs the liver to produce even more sugar to ensure its own prioritized needs are met. This results in an over-production of sugar which shows up as the "Dawn Phenomenon". To combat this, one could eat 10 ounces or so of green beans before going to bed. Green beans have the amino acids and tryptophan to carry you through the night. It may or may not prevent the Dawn Phenomenon altogether, but it should help lower it. (And don't forget to add salt.)

Type 1 Diabetic for 46 years now; kill me already. Boost nutrient drinks won't do as much for blood sugars as getting proper nutrients will. So no, I would not rely on that for blood sugar control.