Common dietary sugar is made up of two saccharides: glucose and fructose. In a free state, it is found in all sweet fruits, honey. It used to be thought that fructose is a sugar substitute for diabetes because insulin is not needed for its penetration into cells, unlike glucose. The lack of a carrier protein activated by insulin, or the insensitivity of cells to it, leads to the accumulation of sugar in the blood, which is dangerous for all body systems, and for the pancreas it is generally fatal. So what is the substitute for sugar for diabetics? 
Studies in both healthy and diabetic subjects have shown that fructose causes less postprandial increases in plasma glucose and serum insulin levels than other common carbohydrates. 
Fructose instead of sugar in diabetes
What made you look at fructose differently? Modern research has shown that humans lack enzymes that can process it. Because of this, it enters the liver, where glucose and bad cholesterol are formed from it, and most often it turns into fat and contributes to the accumulation of its subcutaneous deposits. In addition, fructose is high in calories, and although it is positioned as a diabetic product, in fact, it increases cravings for sugary foods and increases appetite. How to give up sweets in diabetes? First of all, you need to give up sugar in its pure form, and use sweeteners or sweet fruits in small quantities as sweet (with the exception of grapes, bananas). At least their fiber slows down the absorption of carbohydrates. Fans of flour desserts first need to limit themselves in portions, and then gradually learn how to cook them themselves or buy them in grocery stores in special departments. 
Can fructose be used for type 1 and type 2 diabetes?
The attitude to fructose is very controversial, in scientific publications the results of numerous studies are cited, which exclude each other. Nevertheless, its molecules are found in 90% of all products in the world, including those on the shelves of diabetics. It is believed that diabetics can consume fructose if they strictly count and control the units of bread entering the body, and in type 1 diabetes, it is possible to adjust the dose of insulin. 
Fructose in pregnancy diabetes
Changes in hormonal levels in pregnant women sometimes lead to the development of diabetes, which is called "gestational". His main treatment is diet therapy. It involves a decrease in the daily energy value of the diet by an average of one third, mainly due to a decrease in the total amount of carbohydrate intake. Fast foods should be removed from the diet altogether and replaced with complex ones, rich in dietary fiber. Any sugar substitutes, including fructose, are contraindicated for pregnant women, because can negatively affect embryonic development.  It has been shown that dietary fructose or low protein intake during pregnancy can exacerbate already impaired glucose homeostasis, causing gestational diabetes and fatty liver.