Liquid nutrition is having a moment. From kombucha teas to high-priced “cleanses,” grocery stores are devoting whole aisles to a rash of new beverages that claim to energize your mind, trim your waistline, and supercharge your body. But while some offer legitimate health perks, “no drink is going to offer you a magic bullet against whatever ails you,” promises Mayo Clinic’s Katherine Zeratsky, RD, LD.

Here’s what Zeratsky and other nutrition experts have to say about the trendiest health drinks on the market:

Coconut Water

The Claim: Billed as “Mother Nature’s sports drink,” coconut water is a dehydration-slaking, nutrient-restoring alternative to plain H20 or more “synthetic” workout recovery beverages.

The Cost: $3 and up for roughly 16 oz

The Truth: Coconut water contains a lot of potassium—more than a medium-sized banana—as well as electrolytes, which help your body absorb H20, explains Manuel Villacorta, MS, RD, author of Peruvian Powerfoods. But if you’re refueling after a serious workout, coconut water alone won’t be enough to replenish what your body has lost, he adds. And if you haven’t been exercising? Don’t let the word “water” fool you into thinking this beverage isn’t caloric, Zeratsky warns. “People tend to lose track of the calories they consume in beverages. But if you’re drinking a bottle or two of coconut water a day instead of water, that extra 100 or 200 calories will add up,” she stresses.

Almond Milk

The claim: A healthy, humane alternative to cow’s milk.

The cost: $4 for a 65-oz carton

The truth: All “milks” are not created equal—especially when it comes to protein, explains Jennifer Koslo, PhD, RD. “Almond milk has about one gram of protein per serving, compared to eight or nine grams in cow’s milk,” Koslo says. Almond milk also lacks dairy’s branch amino acids, which—along with protein—aid muscle health and growth, Villacorta adds. If you’re lactose intolerant and need something to splash on your morning cereal or in your coffee, almond milk is a good choice, Koslo says. “But even if your almond milk is fortified with vitamin D and other nutrients, you’re not getting the same benefits you would from cow’s milk,” she adds. For those worried about the humane treatment of cows, stick to local and organic dairy products, Villacorta suggests.

Kombucha

The claim: Thanks to its bacteria content, this fermented “probiotic” tea bolsters your immune and digestive systems by supporting the microorganisms that live in your gut.

The cost: $4 and up for 16 oz

The truth: “More and more, we’re learning about the value of bacteria and probiotics to maintain a healthy population of microorganisms in our digestive systems,” explains Stephanie Maxson, MS, RD, a senior clinical dietician at the University of Texas MD Anderson Cancer Center. Kombucha tea—as well as other fermented foods like yogurt and kefir—are good sources of probiotic microorganisms, so they may support your digestive or immune systems. But at this point, it’s not clear which types of bacteria are necessary for optimal digestive health, Maxson says. “Because everyone’s microbiome is unique, people will react differently to different strains of bacteria.” Also, there’s some concern that people living with illness—particularly AIDS or cancer—may be at greater risk for infection from the bacteria in unpasteurized, fermented drinks like kombucha tea, Maxson says. If you’re healthy and don’t mind the cost, she recommends drinking no more than an ounce or two of kombucha a day. “It usually comes in a big bottle, which has enough bacteria to last you a week,” she says.

Green Juice



The claim: There are many varieties of this “super” beverage, but nearly all tout the same benefit: a huge helping of healthful fruits and veggies packed into a convenient, easy-to-swig package.

The cost: $3.50 (and up) for 15 oz

The Truth: Plant enzymes oxidate quickly, so your drink has to be really fresh for you to get all the ingredients’ nutritional benefits, Villacorta explains. As a result, a lot of pre-bottled, commercially sold green juices aren’t fresh enough to offer you the most bang for your buck. And even the fresh-squeezed options won’t provide the full range of nutrients you’d get from eating whole fruits and vegetables, he says.

Chia Seed Juice



The claim: Chia seeds are loaded with fiber, which supports digestion, as well as omega-3s, protein, calcium, magnesium, and antioxidants.

The cost: $3.50 for 10 oz

The truth: Chia seeds are good sources of fiber, and also contain healthy vitamins, nutrients, and some omega-3 fatty acids, says Susan Bowerman, MS, RD, assistant director of the UCLA Center for Human Nutrition. But these drinks tend to have a lot of other ingredients—like sugar—that make them high in carbs and calories, she adds. Also, it’s a lot cheaper to make your own chia seed drinks, Koslo adds. “Just add the seeds to a smoothie and save yourself some money,” she recommends.

Juice Cleanses



The claim: Whether you last a day or a week, a juice cleanse can supercharge your energy levels, help you lose weight, flush out your clogged digestive system, and sharpen your brain.

The cost: $7 to $10 for 16 oz

The truth: Drinking the juice of a fruit or vegetable is not as good for you as eating it whole, Zeratsky says. “Nearly all the fiber and a lot of the nutrients are contained in the flesh, so don’t let the marketing fool you into thinking drinking a juice is the same as eating the whole vegetable,” she warns. And while these cleanses are convenient, they’re also a lot more expensive than buying whole fruits and vegetables, Bowerman adds. “If people can afford cleanses and they want to drink them once in a while to supplement their regular diet, that’s fine. But they shouldn’t be consumed on their own for extended periods, because they’re not nutritionally complete,” she explains.

Aloe Vera Drinks



The claim: They support immune and digestive health, and aid weight loss.

The cost: $2.50 for 16 oz

The truth: “I’ve heard anecdotally that aloe vera can be good for digestion, but there’s really not much science behind it,” Koslo explains. She says there are also some reports of complications like diarrhea and cramps from drinking too much of these beverages. “No dietician is going to tell you you need to get aloe vera in your diet,” she adds. “If you want to drink it, there may be some benefits. But I would do so sparingly.”

Hemp Milk



The claim: Another vegan alternative to dairy milk, this beverage provides omega-3s and plant-based nutrients.

The cost: $6 for 32 oz

The truth: Like almond milk, you shouldn’t think of this hemp-based option as a comparable replacement for cow’s milk, Bowerman says. “Most are not as high in protein.” On the other hand, hemp milk does offer you some omega-3 fatty acids, although not the super-beneficial type found in fish, Koslo adds. “If you have a milk allergy, this could be a good alternative. But you’re not going to get the same protein and nutrients that mammalian milk offers,” she explains.

Maple Water



The claim: It’s low-cal and loaded with super-hydrating “bioactive compounds” including vitamins, nutrients, and polyphenols—some of which promote thyroid and bone health.

The cost: Roughly $3.50 for 11 oz (although it’s not yet widely available)

The truth: The product is so new that there’s little research out there on its health benefits, Villacorta says. And while there’s some research touting maple syrup as a source of healthy antioxidant compounds, that doesn’t mean maple water will offer the same compounds in nutritionally significant quantities, he says. Maple water is supposedly high in antioxidants as well as manganese, which assists thyroid health, bone strength, and vitamin absorption, says Lilian Cheung, RD, of the Harvard School of Public Health. “But these claims are not verified by scientific studies,” Cheung adds.

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