Are nondairy milks the right option for people looking to get in shape for the new year? The answer has become less clear-cut as more plant-based milks have hit the market.

"Consumers are very confused about the nutrition quality of different types of plant milks, and there are a lot out there," says Consumer Reports nutritionist Amy Keating.

Consumer Reports tested plant-based milks made from almonds, coconuts, oats and soy.

Studies found that soy milk came closest to cow's milk in terms of providing high-quality protein and nutrients. Almond milk, however, tested very low in protein.

Tests also found that coconut milk is low in protein and contains saturated fat. Oat milk was found to have some protein and fiber.

Consumer experts also advise those buying plant-based milks to check the label to look for one that's carrageenan-free. Carrageenan is a gum that can irritate the stomach. Other nondairy milks may contain phosphates, which some research has linked to kidney problems.

They also say that plant milks marked as "plain" or "original" could have added sugar. Those looking to avoid sugar should look for milks specifically labeled "unsweetened."