Sales of almond milk have taken off like a bottle rocket in recent years as people embraced the product as an alternative to dairy and soy milk.

As a milk substitute, almond milk is popular with people who are lactose intolerant, allergic to gluten, have heart disease or simply want to reduce their consumption of animal products. It can also be a tasty alternative to rice or soy milk.

But in the wake of a lawsuit against a top almond milk producer, many consumers are asking what’s really in store bought almond milk — and whether it’s actually good for you.

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Almond milk milking consumers?

A class-action lawsuit filed in July against top almond producer Blue Diamond Growers claims the company’s packaging for its Almond Breeze beverage is false advertising and misleads consumers into thinking the milk’s almond content — and health benefits — are more significant than they are. Filed in the state of New York, the suit claims Almond Breeze contains only 2 percent almonds. Rival product Silk Pure Almond is the target of a similar suit.

U.S. regulations on food labels do not require manufacturers to specify the percentages of ingredients such as almonds. While the percentage of nuts in Almond Breeze is not listed on the package in U.S. grocery stores, it’s available on Blue Diamond Grower’s U.K. website — yep, 2 percent.

So what else is in Almond Breeze’s “almond milk”? Turns out it’s mostly water, with a hint of almonds and some salt, starch, stabilizers and flavoring. Besides almonds, its listed ingredients are spring water, calcium carbonate, tapioca starch, sea salt, stabiliser: carrageenan; emulsifier: sunflower Lecithin; natural flavoring.

But wait: The primary ingredient in nearly all popular beverages, “including coffee, tea, soda, juice and sports drinks, is water,” Blue Diamond told TIME magazine in response to the lawsuit. “Cow’s milk is 85 percent to 95 percent water, and the same can be said for most soy and almond milks, which is why our brand is not alone in responding to recent claims.”

Nonetheless, there is legal precedent for a case like this, says attorney Lauren Handel, JD, LLM, a partner in the law firm Foscolo & Handel PLLC, which specializes in food and farm business litigation. She points out there are “lots and lots of lawsuits alleging that food labeling is deceptive.”

“It’s not alleging that they (Blue Diamond) are violating FDA rules, because they probably are not,” Handel says, pointing out that only drinks that contain juice are required by U.S. law to specify the exact amounts of ingredient they contain. “Here, the question is if they are deceiving consumers about the quantity of the ingredients or by calling it milk. A lot of these cases now have to do with foods that are labelled ‘natural’ but contain synthetic ingredients or are highly processed.”

“With most of these cases, the money to be made is through class action. Not one of these cases has gone to trial,” she says. “Some are getting dismissed before trial, but the vast majority get settled. With the big companies the settlements run into the millions of dollars.”

In addition to the lawsuits, U.S. almond growers — who produce more than 80 percent of the world’s almonds — have another headache: about 9 percent of California’s agricultural water is devoted to growing almonds, raising concerns about the almond crop’s environmental impact as the state struggles under the fourth year of a blistering drought.

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“No extra nutrition” in almond milk

Consumers can use almond milk “as an alternative to dairy milk in cereals or drinking to cut down on calories and carbs,” says registered dietitian Rebecca Mohning, RD, MS, based in Washington, D.C. But, she says, “There’s no extra nutrition in almond milk as opposed to other types of milk unless the product is fortified with vitamins and minerals.” (By federal law, dairy milk must be fortified with vitamins A and D.)

And sometimes the nutritional value in dairy milk alternatives falls short in comparison. One cup of whole milk has about 8 grams of protein, Mohning notes, while a cup of almond milk has slightly less than 2 grams.

“Some almond milk products are fortified with calcium, but you could get too much calcium if you drink too much,” Mohning says. “Calcium buildup can cause kidney stones, bone spurs, calcium build-up in the arteries and build-up in the body.”

Mohning and other dietitians also caution that substitutes for dairy milk are not nutritious enough for children younger than one year. In addition, some almond milk beverages contain carrageenan, a seaweed derivative used as a stabilizer and thickening agent. Animal and human cell studies show that carrageenan may cause gastrointestinal inflammation, including ulcerations and bleeding.

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Steve Evans, MA, is an award-winning journalist with more than 20 years experience in daily news, investigative, health and business journalism. Among other jobs, he has served as managing editor of the Central Virginia Newspaper Group, as a senior writer for SNL Financial and as a staff writer for The Progress Index and the Richmond Times-Dispatch.