According to another study published in 2016, those with diabetes are usually less sensitive to a sweet taste. It leads to a craving for sugar consumption which increases the condition of diabetes such as inflammation, cardiovascular accident or weakened the immune system.
Various kinds of infections can contribute to a constant sweet-taste in the mouth. Scientists said that virus and bacteria could have the bad impact on the nerves which results in some changes in tastes. For example, a bacterium called Pseudomonas causes Pseudomonas infection which can cause sinusitis together with changes in taste including a sweet taste in the mouth.
According to a study by the National Institutes of Health published on its website, people suffering from blocked sinuses caused by inflammation have changes in taste including a sweet taste in the mouth.