Drinks aren’t just about hydration and flavor anymore. From detoxifying tonics to brain-boosting nootropics, beverages promise a vast—and growing—array of health benefits.
The market for these “functional beverages” has exploded in recent years. Already valued at $50 billion, the market is expected to continue growing. Despite the booming interest, some worry that the industry may have outpaced the science.
“There are thousands of natural compounds in foods that we’re learning about that are important for the body, and that really do have functional benefits,” says Dariush Mozaffarian, cardiologist and director of the Food is Medicine Institute at Tufts University. “But it doesn’t mean that we know that putting some of those isolated compounds in water is going to be good for your health.”
Food science and nutrition experts weigh in on the truth behind some of these big health claims—and how to smartly navigate the functional beverage aisle.
Improved gut healthEvidence shows that consuming fermented foods like kimchi, yogurt, and sauerkraut may confer a whole host of positive effects, from lower blood pressure to improved gastrointestinal health and resilience.
Now, fermented beverages are promising the same health benefits. Prebiotic and probiotic beverages, like apple cider vinegar tonics and kombucha, claim to nourish and diversify the gut microbiome.
But researchers say there are a few reasons to be skeptical.
Nutritionist Marion Nestle, emerita professor of nutrition, food studies, and public health at New York University, says evidence on probiotics is still “quite mixed.” Nestle doesn’t encourage seeking out probiotics except for people taking antibiotics or suffering from serious digestive difficulties. Even then, she says, “Whether they make any difference medically is arguable.”
The exact cocktail of bacteria in probiotic drinks can vary, with Lactobacillus, Saccharomyces, and Bifidobacterium being some of the most common. Even closely related strains of microbes may have vastly different properties, says Maria Marco, professor of food science and technology at UC Davis. While certain strains are well-studied and widely used, others have yet to undergo sufficient lab tests, let alone human clinical trials.
But even if the bacteria are well-studied, they might not be alive by the time you pop the bottle.
“Probiotics, which are living microorganisms, tend to die if you heat them or store them for a while,” says David Julian McClements, professor of food science at the University of Massachusetts. Existing research isn’t clear on whether dead bacteria can still provide health benefits.
There’s also the challenge of getting the probiotics to the gut microbiome intact. McClements explains that the mouth, stomach, and intestine are harsh environments that could degrade probiotics before we get a chance to absorb them.
Getting probiotics through beverages doesn’t seem to be more or less effective than any other form, Marco says. While still in an early stage, research shows that finding the best bacterial strain for your needs—in the right dose and high quality—is more important. Marco suggests starting with products that list the strain type on the label because they’re more likely to contain “a microbe that actually has a scientific basis to be called a probiotic.”
Enhanced cognition Want a cognitive boost? Forget the traditional cup of joe—we’re in the era of brain-enhancing bioactive plant compounds.
Though these newfangled ingredients may be exciting, the newcomers are often propped up by simple, old school methods, says Debbie Fetter, an assistant professor of teaching nutrition at UC Davis. Drinks advertising any kind of “boost” often have some sort of caffeine—whether it’s coffee bean or green tea extract—and sometimes in deceptively high doses, she adds.
One of the buzziest new additives are nootropics, a broad category of so-called “smart drugs” that purport to have cognitive benefits. Proprietary blends of natural nootropics have made their way into functional beverages, promising mood-enhancement, mental focus, and improved memory.
L-theanine, for instance, has been shown in some studies to improve attention, and may benefit working memory and executive function, as well. However, a recent literature review found limitations in the existing research, including small sample sizes and confounding factors. Though L-theanine can be consumed either naturally in tea, or as a supplement in capsule or beverage form, preliminary research suggests it works best with caffeine.
Most studies have looked at nootropic compounds—like L-theanine and extracts from lion’s mane mushroom, ginkgo tree, and ashwagandha root—in capsule form, so their effectiveness in drinks is unknown. But experts generally agree that there’s no hard and fast rule whether a supplement will work better in one form or another.
Some plant-based beverages have shown promise, says Howard Sesso, an epidemiologist at Brigham and Women’s Hospital and Harvard Medical School. Flavonoids, which occur naturally in many plants like onions, grapes, and cocoa beans may have some benefits for cognition, and even heart health. However, early research on cocoa extract has been mixed. One trial found that regular consumption of drinks containing high concentrations of cocoa flavanol reduced age-related cognitive decline, while another recent study saw no effect.
Connecting an ingredient to its supposed benefit is a perplexing task. Fetter explains that plant-based compounds exist in a matrix of others, whose interactions could boost, neutralize, or diminish each other’s effectiveness. Untangling any single ingredient’s role—and recreating that effect in a beverage—is difficult, and proof of concept is limited.
Though the negative side effects of natural nootropics tend to be mild, some drug interactions and health complications are possible, including blood thinning and psychiatric problems. In a 2022 review, the authors said the use of nootropics “cannot be recommended to healthy individuals who do not suffer from any cognitive dysfunction.”
Inflammation reduction and immune supportFrom golden lattes to fresh-pressed juices, functional beverages have marketed themselves as the elixir to a long, healthy, and un-inflamed life.
“Quercetin, turmeric, all of those things have anti-inflammatory effects,” says Simin Meydani, a professor of nutrition and immunology at Tufts University. But whether an infused drink will actually reduce inflammation depends. “Sometimes we see effects in the test tube that we don’t necessarily see repeated in animals or humans.”
When it comes to immune-boosting beverages, Meydani is wary. It’s true that ingredients like vitamin E, vitamin C, and zinc are necessary for a well-functioning immune system. But, unless someone is nutrient-deficient, they’re not likely to benefit from an immunity cocktail, she adds.
There’s simply no need for drinks, like these juices, that advertise “1,350 percent of your daily dose of vitamin C and 188 percent of zinc.” Not only do most people get the majority of their vitamins and nutrients from food, but the benefit from extra vitamins will eventually max out.
Whether we glean the benefits of supplements varies and depends on how they interact with our diet and our bodies.
“The take-home message is: Try to, as much as you can, consume those potentially beneficial compounds in the natural food,” Mozaffarian says. “If you’re going to try to consume them in a functional beverage, [avoid] anything that has excess sugar, or salt, or artificial sweeteners or other artificial additives.”
In other words, be an informed consumer, he says. Approach functional beverages “with the principle of ‘do no harm’” first, and remember that any benefits are not guaranteed.
Source : National Geographic