And many people opt for low-fat options as part of this. Low-fat milk is made by removing or skimming the cream off the milk.

And while there’s not good evidence that low-fat dairy products are a healthier choice for everyone, Dr. Krauss said, people respond differently to different foods.

One study found that foods advertised as “low-fat” might lead people to eat up to 50% more than they might if no claim is made. Though the 300-calorie pints might seem less indulgent, if ...