Consider the following statements in respect of probiotics: 1. Probiotics are made of both bacteria and yeast. 2. The organisms in probiotics are found in foods we ingest but they do not naturally occur in our gut. 3. Probiotics help in the digestion of milk sugars. Which of the statements given above is/are correct?

1. Correct. Probiotics are live microorganisms; commonly they include beneficial bacteria (like Lactobacillus, Bifidobacterium) and sometimes yeast (like Saccharomyces boulardii).

2. Incorrect. Many probiotic organisms are already natural residents of the human gut; probiotics are used to support or restore this gut microbiota.

3. Correct. Certain probiotic bacteria help digest lactose (milk sugar) by producing lactase, so they can help in lactose intolerance.

Hence, statements 1 and 3 are correct.