Saccharin and its salts are useful for diabetic patients.

Answer

**Step-by-Step Solution:**

1. **Understanding Saccharin**: Saccharin is an artificial sweetener that is used as a sugar substitute. It is known for its sweetness without the calories associated with regular sugar.

2. **Caloric Content**: Unlike regular sugar, which contributes to calorie intake, saccharin has zero calories. This makes it particularly useful for individuals who need to manage their calorie consumption, such as diabetic patients.

3. **Metabolism in the Body**: Saccharin is not metabolized by the body. This means that it does not break down into glucose or affect blood sugar levels, which is crucial for diabetic patients who need to control their blood sugar.

4. **Impact on Blood Sugar Levels**: Since saccharin does not get metabolized and does not contribute to blood sugar levels, it is safe for diabetic patients to use as a sweetener without the risk of increasing their blood sugar.

5. **Conclusion**: Given that saccharin serves as a non-caloric sweetener that does not affect blood sugar levels, it is indeed beneficial for diabetic patients. Therefore, the statement that "Saccharin and its salts are useful for diabetic patients" is **True**.

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