Corn is an ideal food for diabetic patients due to its low content of crude fiber and soluble sugars. For example, the sugar content in old corn is 2.3% lower than that of regular rice, while its crude fiber content is nearly 9 times that of rice, all of which help diabetic patients lower their postprandial blood glucose levels. However, there are many varieties of corn, and some are not suitable for diabetic patients to eat.
For instance, sweet corn has a soluble sugar content that is 2% to 15% higher than that of rice, most of which is sucrose, glucose, and fructose, which can easily cause blood sugar to rise after consumption. In addition, waxy corn has a high content of amylopectin, which is easily digested and absorbed, causing blood sugar to rise faster than other grains after consumption. Therefore, it is not advisable to eat it alone; it can be paired with bean flour or foods rich in dietary fiber to slow the rise in blood sugar. Black corn is mostly waxy as well, so it is best to eat it with coarse grains like bean flour or oats.