March 2022 Issue

Functional Beverages
By Mindy Hermann, MBA, RDN
Today’s Dietitian
Vol. 24, No. 3, P. 20

Sales of these specialty products promising a wealth of health benefits are booming. But are their lofty claims supported by research?

The term “functional beverage” encompasses a wide variety of products that tout health and wellness benefits, such as energy drinks, fortified juices and waters, sports drinks, milk and dairy beverages, dairy alternative drinks, tea, and coffee. Most feature added ingredients that claim to confer functionality—for example, ginseng to boost energy—while some naturally contain functional compounds such as caffeine. Functional beverages have become so popular that they accounted for 60% of new US beverage launches between July 2020 to June 2021, according to a proprietary report from Innova Market Insights on functional beverages in the United States.

The recent report, “Functional Beverages: Market Trends and Opportunities” by Packaged Facts, predicted that functional beverage sales would reach nearly $49 billion by the end of 2021. The global flavor and fragrance formulator Firmenich named “Magical Botanical” as its 2022 Flavor of the Year, which is inspired by the healing potential of botanicals to meet “a transformed society’s need for enhance well-being and creativity,” according to a company press release. Botanicals often are featured in functional drinks.

The pandemic has helped propel growth in the functional beverages category as consumers become more aware of and concerned with their health. Moreover, many of the latest functional drinks contain new blends of high-intensity, zero-calorie sweeteners, including stevia and monk fruit, that significantly reduce calories, offering consumers a lower-sugar alternative to soft drinks.

What’s more, the functional benefits touted have expanded in recent years. In the past, they mainly focused on boosting energy by providing caffeine and other types of stimulants. While energy drinks still are popular, there are other products gaining shelf space, such as those that target digestive health, weight management, immunity, healthier bones and skin, and cognitive health, as well as stress relief, better focus, mood improvement, relaxation, and sleep.

According to their marketing, functional beverages offer consumers a shortcut to a seemingly healthful lifestyle by circumventing the need to change eating habits, incorporate physical activity, or take supplements. These products are readily accessible in supermarkets, packaged with eye-catching labels and positioned with claims to solve problems of everyday life and health.

For many consumers, the colorful packaging, creative names, appealing flavors, and functional promises are alluring. “Functional beverages are convenient, interesting, and delicious,” says Erin Skinner, MS, RD, LDN, IFNCP, owner of Empowered Nutrition in Southern Pines, North Carolina. “Beverages feel less clinical and more holistic than pills and powders. They also provide specialized nutrients and ingredients in an easy-to-buy grocery store product. A supplement is a chore, while a delicious beverage is a treat.”

This article reviews several on-trend categories of functional drinks such as adaptogens, probiotics for digestive health, and vitamin enriched, as well as those containing coenzyme Q10 (CoQ10) and collagen, and others that undergo fermentation.

The COVID-19 pandemic and its impact on daily routines have affected mental health in the United States. A nationwide survey of psychologists, “Stress in America 2021,” conducted by the American Psychological Association, found that significant numbers of people are seeking treatment for anxiety, depression, sleep disorders, and other aspects of mental health.1 According to the CVS Health 2021 Health Care Insights Study, stress levels are up as a result of the pandemic and at least 30% of those surveyed report anxiety, sleep changes, and depression.2 This decline in mental health and increased interest in treatment may help explain the current appeal of adaptogenic beverages.

Adaptogens have their roots in Ayurvedic medicine. They’re natural substances thought to support health by helping the body handle stress, maintain normal metabolic activity, and improve various aspects of mental function. Nootropic adaptogens—substances positioned to improve brain performance—are gaining attention for their promise to enhance focus, concentration, memory, and other aspects of cognitive health.

Functional drinks incorporate several key adaptogens alone or in combination. Ashwagandha, a member of the nightshade family, is promoted for boosting oxygen use during exercise, as well as improving brain function, combating anxiety and depression, and lowering blood sugar. A recent meta-analysis concluded that ashwagandha supplementation is more effective than placebo at enhancing physical performance in healthy men and women, but that further study is needed.3

Schisandra contains numerous antioxidants and is said to offer several functional benefits, including relief of menopause symptoms and improving exercise performance. The stimulant caffeine boosts cognitive performance. L-theanine, found in green tea leaves and some mushrooms, is marketed for anxiety reduction and as a sleep aid. Ginkgo, an ancient adaptogen with roots in traditional Chinese medicine, is promoted for decreasing anxiety and enhancing mental clarity. Reishi mushrooms often are associated with immune-boosting properties. Ginseng is said to act therapeutically against inflammation, diabetes, and heart disease.

Keep an eye on terpenes, naturally occurring compounds responsible for the smells of many plants but commonly associated with hemp and cannabis. They’re increasingly being incorporated into functional drinks for various adaptogenic benefits. Myrcene, the most prevalent of the more than 200 terpenes in cannabis, is promoted to relieve inflammation and pain, relax muscles, and aid sleep. Betacaryophyllene, a dietary cannabinoid, is thought to relieve pain and protect the nervous system.

The benefits of many adaptogenic beverages aren’t well substantiated. Functional ingredients often act holistically in the body, making it difficult to measure their effects. Their physiological effects may differ when taken in combination with other ingredients.4 Amounts of active ingredients aren’t standardized, active compounds may have limited bioavailability, and formulation processes may not be optimized for efficacy in the body. Additional drawbacks can include bitter taste, sediment caused by limited solubility of functional ingredients, and high cost.

Probiotics, Prebiotics, and Postbiotics
Probiotic beverages are positioned to improve various aspects of health by improving the balance between beneficial and pathological strains of bacteria in the gut. According to the International Scientific Association for Probiotics and Prebiotics, a nonprofit organization that advocates probiotic and prebiotic science, probiotics are “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” The organization states, “Only characterized strains with a scientifically demonstrated effect on health should be called probiotics.” As summarized by the National Center for Complementary and Integrative Health, a government agency under the National Institutes of Health that explores complementary and alternative medicine, probiotic strains have shown potential to prevent antibiotic-associated diarrhea, prevent necrotizing enterocolitis and sepsis in premature infants, treat infant colic, and induce or maintain remission in ulcerative colitis.5

Due to these health benefits, probiotic beverages continue to evolve. In the past, probiotic beverages typically were formulated with a dairy base using one or more specific bacteria strains targeted to gut health benefits. Today’s probiotic beverages may be developed for additional functionality such as brain health and immunity. They’re also available in plant-based beverage formulations, featuring strains cultivated for use in nondairy products, and sales are growing rapidly. Beverages may be formulated using less familiar probiotic strains such as Bacillus coagulans, which can grow well in a nondairy medium, or Bacillus subtilis, a strain that can withstand heat and harsh processing conditions. Names such as “water kefir” help identify beverages that use dairylike cultures in a water or plant-based format rather than milk.

Newer products also include both probiotics and prebiotics. Prebiotics are soluble fibers nondigestible by humans. They travel to the large intestine where they help nourish and boost the health impact of probiotic microbe strains such as bifidobacteria and lactobacilli. The FDA recently added the prebiotic acacia gum to its approved list of prebiotic isolated or synthetic nondigestible carbohydrates that qualify as dietary fibers, joining glucomannan, some types of resistant starch, inulin and inulin-type fructans, glucooligosaccharides, and several others. An added benefit to prebiotics such as inulin and its related compounds is that they’re naturally sweet, enabling manufacturers to reduce the amount of sugar in their products.

Consumers should expect growth in functional beverages made with prebiotic ingredients. FDA approval has opened the door to greater use of these ingredients in beverages marketed to improve gut health. In addition, expanded ingredient choices and processing methods are leading to ongoing changes to probiotic and prebiotic beverages. Researchers and entrepreneurs are exploring ways to maintain the viability of probiotic strains in beer and other types of alcoholic beverages. For example, probiotic shots use strains such as B coagulans that can remain viable in juice and other types of bases rather than the traditional dairy base. Watch for herbal coffee and tea alternatives enriched with prebiotics plus adaptogens. An April 2021 report on prebiotics by Global Market Insights, Inc, predicts that the total prebiotics market, which includes prebiotic beverages, will surpass $9.5 billion by 2027, with estimated growth of more than 10.2% compound annual growth rate from 2021 to 2027.6

Dietetics professionals can help clients understand the differences among products, including the meaning of various “-biotics” and their potential benefits. Look-alike terms such as probiotics and prebiotics can be confusing to average consumers. In fact, the latest term, “synbiotics,” is used to define products containing both probiotics and prebiotics. It’s growing in use on supplements and baby formulas and has started to appear on some functional beverage labels. Postbiotics describe the microbes (both viable and dead) and metabolic products associated with the fermentation of beverages such as kombucha. For many products, marketing promises are ahead of the science of “-biotic” beverages.

Vitamin Enriched
Vitamin-enriched beverages are well established and becoming more nuanced than they were a generation ago when first introduced as vitamin waters. In addition to water, juices, dairy drinks, and plant-based dairy alternatives are being fortified. Specific claims associated with certain vitamins are increasingly common. The inclusion of vitamin D on the Nutrition Facts panel appears to have sparked several new product launches providing high percentages, even up to 100% DV for vitamin D.

Beverages With CoQ10
The vitaminlike compound CoQ10 is moving away from heart health, where it’s associated with reduced serum levels among statin users, and venturing into other aspects of human health. Newer functional beverages include CoQ10 combined with branched-chain amino acids and other ingredients for improved energy and recovery. One niche in which functional beverages highlight CoQ10 as an antioxidant is skin health and regeneration. A recent review article suggests that supplementation with CoQ10 may play a role in the prevention of migraines, neurodegenerative diseases, cancer, or degenerative muscle disorders, although beverages with CoQ10 aren’t yet being marketed to prevent these conditions.7

Collagen-Containing Drinks
The inclusion of collagen in beverages suggests that ingesting collagen can directly improve skin, as well as other parts of the body with concentrated amounts of collagen, such as hair, nails, and joints. Collagen also has gained popularity among followers of the keto diet. Research on the relationship between collagen supplementation and health and beauty benefits is expanding. In a study on a group of women aged 45 to 59, daily supplementation for 90 days with 500 mg hydrolyzed fish cartilage as the collagen source was associated with minor improvements in skin appearance.8 Overall evidence, however, remains weak. A review article that compared collagen skin health claims on social media and company websites with literature concluded that more research is needed to justify collagen supplementation.9 In a review of 15 articles, 12 of which were on recreational athletes, 15 g collagen daily improved collagen synthesis rates but didn’t impact muscle protein synthesis when compared with higher-quality protein sources.10 Questions remain on whether ingesting collagen directly benefits collagen production in the body and whether higher-quality protein sources may have an equal or superior effect.

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Implications for Dietetics Practitioners
Functional beverages can be an expensive path toward obtaining health benefits, especially when compared with supplements and food sources. In addition, the functional properties of many ingredients in functional beverages aren’t well supported. “Functional drinks promise to boost energy, improve thinking ability, and bolster gut health at all stages of a woman’s life, but it’s important to remember that data support on functional beverages is weak,” says Elizabeth Ward, MS, RDN, coauthor of The Menopause Diet Plan: A Natural Guide to Hormones, Health, and Happiness, and a nutrition consultant in the Boston area. “As with any food, moderate intake of functional drinks is probably OK, but I suggest that pregnant and breast-feeding women, as well as women who are being actively treated for medical conditions, tell their dietitian and medical team about the functional beverages they’re consuming just to be sure. Also, it’s possible to go overboard on micronutrients when women regularly consume drinks with added vitamins and minerals in addition to dietary supplements and fortified foods.”

Skinner cautions that “functional beverages are not well controlled or regulated, so the purity, quality, and dosing of the functional ingredients they contain isn’t guaranteed. Functional beverages introduce risk while not necessarily providing any clinical benefit. Furthermore, the dosing of functional ingredients is often very low, below what is typically shown to provide clinical outcomes. Finally, the price of functional beverages is typically higher than that of a quality supplement.”

— Mindy Hermann, MBA, RDN, is a New York–based food and nutrition communications consultant.


1. American Psychological Association. Stress in America 2021: stress and decision-making during the pandemic. Published 2021.

2. Health Care Insights Study 2021. CVS Health website.

3. Bonilla DA, Moreno Y, Gho C, Petro JL, Odriozola-Martínez A, Kreider RB. Effects of ashwagandha (Withania somnifera) on physical performance: systematic review and Bayesian meta-analysis. J Funct Morphol Kinesiol. 2021;6(1):20.

4. Gerontakos SE, Casteleijn D, Shikov AN, Wardle J. A critical review to identify the domains used to measure the effect and outcome of adaptogenic herbal medicines. Yale J Biol Med. 2020;93(2):327-346.

5. Probiotics: what you need to know. National Center for Complementary and Integrative Health website. Updated August 2019.

6. Prebiotics market size by ingredients (fructo-oligosaccharide (FOS), inulin, galacto-oligosaccharides (GOS), mannan-oligosaccharide (MOS)), by application (prebiotic food & beverages {dairy products, cereals, baked food, fermented meat products, dry food prebiotics}, prebiotic dietary supplements {food supplement, nutritional supplements, specialty nutrients, infant formula}, animal feed prebiotics) industry analysis report, country outlook application development, price trends, competitive market share & forecast, 2021–2027. Global Market Insights website. Published April 2021.

7. Testai L, Martelli A, Flori L, Cicero AFG, Colletti A. Coenzyme Q10: clinical applications beyond cardiovascular diseases. Nutrients. 2021;13(5):1697.

8. Campos PMBGM, Franco RSB, Kakuda L, Cadioli GF, Costa GMD, Bouvret E. Oral supplementation with hydrolyzed fish cartilage improves the morphological and structural characteristics of the skin: a double-blind, placebo-controlled clinical study. Molecules. 2021;26(16):4880.

9. Rustad AM, Nickles MA, McKenney JE, Bilimoria SN, Lio PA. Myths and media in oral collagen supplementation for the skin, nails, and hair: a review [published online October 25, 2021]. J Cosmet Dermatol. doi: 10.1111/jocd.14567.

10. Khatri M, Naughton RJ, Clifford T, Harper LD, Corr L. The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise: a systematic review. Amino Acids. 2021;53(10):1493-1506.