Start by bringing a large pot of salted water to a rolling boil over high heat.

Add the elbow macaroni to the boiling water and cook for about 10 minutes, stirring occasionally. Drain and rinse under cold water.

In a medium mixing bowl, whisk together the mayonnaise, white vinegar, granulated sugar, and whole milk until smooth and creamy.

Once the pasta is cooled, add it to the bowl with the dressing along with the shredded carrots and flaked tuna. Gently fold everything together.

Cover the bowl with plastic wrap or transfer to an airtight container, then refrigerate for at least 30 minutes.