Ten years ago, the non-dairy options at your local coffee shop were likely soy or almond milk. Today, non-dairy drinkers have their pick of the litter, including the ever-popular oat milk and other options like pea, hemp, cashew and even banana milk. 

The market is growing – a food and drink analyst told The New York Times that plant-based milk will likely make up 30% of total milk sales by the end of 2026.

Many gravitate toward non-dairy milk because of an allergy or intolerance, but some prefer it because of its lesser environmental impact. Compared to dairy milk, non-dairy milk production uses less land and water and yields lower greenhouse gas emissions.

What is the healthiest milk alternative?

The healthiest milk alternative is soy milk because it’s nutritionally comparable to dairy milk, says registered dietitian Jamie Nadeau.

Dairy milk is an important source of protein, calcium, vitamin D and other nutrients. It contains 8 grams of protein per cup while soy milk contains just over 6 grams per cup. The numbers may differ based on brand, but generally, oat milk has just 3 grams per cup, almond milk has a little more than 1 gram and coconut milk has even less.

Fortified soy milk contains similar amounts of calcium and vitamin D as cow's milk and therefore counts toward your daily dairy intake, the U.S. Department of Agriculture says. It's also generally a low carbohydrate option compared to other non-dairy milks, as long as it doesn’t have a lot of added sugar, Nadeau says. Coconut milk is another low-carb option. 

“Something like oat milk or rice milk would be a little bit higher naturally in carbohydrates just because of what it’s made from,” Nadeau says.

But if you don't like the taste of soy, how do you choose another option that’s both tasty and nutritious?

If you’re just adding a little bit to your coffee, Nadeau says it’s okay to prioritize preference. But if it's your main source of calcium, compare labels and find a fortified option. Every brand is different – some contain minimal ingredients while others have added sugar and flavorings. 

“Almond milk, rice milk, coconut milk, cashew milk, they are all super, super similar. Even oat milk is pretty similar as far as what you’re getting nutritionally,” Nadeau says. “You have to look at which ones have the most sugar added.”

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Is soy milk good for you?

Yes – soy is a complete protein source, meaning it contains all nine of the essential amino acids that our bodies can’t make on their own. It’s also rich in B vitamins, fiber, potassium and magnesium and has a “modest, yet clinically relevant” cholesterol-lowering effect.

Does soy milk have estrogen?

Soy contains isoflavones, a type of plant estrogen that functions similarly to human estrogen but with weaker effects. The internet is fraught with claims that these phytoestrogens cause breasts to grow or increase the risk of breast cancer. 

This is false, USA TODAY’s Fact Check team found. In theory, too much phytoestrogen could stunt breast size, not grow it. And while consuming too much isoflavone could increase the risk of hyperestrogenism, experts told USA TODAY that will likely never happen from the consumption of soy milk or almond milk. 

The American Cancer Society says there is no evidence of soy causing harm, especially with breast cancer risk. One study even suggests that eating soy foods may lower breast cancer risk among Asian women.

Discover more health tips for your daily diet: 

• Healthiest nut: Add these two daily for cognitive benefits and more
• Healthiest cereal: Inside the nutritional info on the back of the box
• Healthiest ice cream:What to know before grabbing a “healthy” ice cream
• Healthiest smoothie:Try out these ingredients in the blender
• Healthiest yogurt:This type packs the most protein

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