Are There Benefits to Chlorophyll Supplements?

The therapeutic potential of chlorophyll — and its semi-synthetic derivative, chlorophyllin — has intrigued scientists for much of the past century.

Chlorophyll is all around us: in the verdant trees, in the spinach at the salad bar, on the shelves of stores. It’s a popular ingredient in products that promise fresher breath, more energy and radiant skin. The actor Reese Witherspoon says that when she adds a little chlorophyll to her water, her acne clears up. Rosario Dawson reportedly drinks it to help with altitude sickness. This summer, Mandy Moore shared a recipe for a refreshing chlorophyll drink, with a “pinch” of this, and a “squeeze” of that, as if it had come from a family cookbook.

Consumers in the United States spent $7.8 million on chlorophyll supplements last year, up 66 percent from a decade earlier, according to Nutrition Business Journal. While sales of supplements with chlorophyll have dipped in 2019, those of infused drinks, breath fresheners and topical products — like facial cleansers, exfoliants and facial masks — have increased, according to SPINS, a wellness-focused data technology company in Chicago.

Does chlorophyll do anything?

Laboratory studies suggest that chlorophyllin may have antioxidant properties, which help to combat the damage to our cells caused by harmful molecules known as free radicals. However, most of the available scientific research for chlorophyll and chlorophyllin comes from cellular and animal studies; there haven’t been many human trials.

“There actually isn’t enough scientific evidence to determine if chlorophyll is beneficial for any medical purpose right now,” said Chelsey McIntyre, a pharmacist and an editor of Natural Medicines, a database that provides information on supplements, herbal medicines and other alternative treatments. The same goes for chlorophyllin, which is often used in supplements, or in food dyes. But, anecdotally, its reputation as a multipurpose curative has flourished.

Reports of chlorophyll’s odor-fighting powers wafted out of an army hospital in 1947, where the stench of injured patients filled the corridors. That was, apparently, until a chlorophyll derivative arrived on the scene. “This odor immediately disappeared,” Lt. Col. Warner F. Bowers wrote in The American Journal of Surgery.

Fanned by mass advertising, the lore of chlorophyll grew, especially during the 1950s, when many Americans reached for it in the form of toothpaste, mouthwash, dog food and — yep — cigarettes. Clorets, a gum made with the ingredient, touted breath that became “kissing sweet” in seconds.

Timothy Jay, a professor emeritus of psychology at the Massachusetts College of Liberal Arts, wrote about chlorophyll’s popularity in a book-length history of surprising social mores titled “We Did What?!” He chalked up its current faddishness to a “generational variable.” “Younger consumers are generally not aware of the history of personal care/nutritional claims of the 50s,” he wrote in an email, “so they can be duped like our grandparents were years ago.”

In a 1980 study, researchers dispensed daily chlorophyllin tablets to 62 female patients at a nursing home for six months. At the beginning, half of them were incontinent, with a strong smell; the other half struggled with constipation and flatulence. The first group reportedly improved by 85 percent and the second by 50 percent.

“It’s hard to objectively measure that effect,” said Dr. Timothy Gardner, a gastroenterologist and an associate professor of medicine at Dartmouth’s Geisel School of Medicine. Not only did this study lack a control group, he said, but it has not been replicated in the nearly 40 years since. He believes there was a large placebo effect and said there’s not enough evidence for chlorophyll or chlorophyllin’s use for constipation, flatulence or reducing body odors.

Another area where doctors say more research is needed is cancer prevention. Chlorophyllin may protect against aflatoxin, a toxin made by fungi and known to contaminate food in the area around Qidong, China. At the time of a 2001 study, it was a big problem there, since dietary exposure to aflatoxins increases the likelihood of developing hepatocellular carcinoma, a type of liver cancer.

In the randomized, double-blind, placebo-controlled trial, 180 residents of Qidong were told to take three pills a day, one before each meal. They either received three 100-milligram doses of chlorophyllin or three placebo pills. Urine samples showed that chlorophyllin consumption for four months was associated with a 55 percent reduction of the aflatoxin DNA damage biomarkers compared to those taking the placebo.

“The efficacy was demonstrated by the reduction in the DNA damage,” said John D. Groopman, the Edyth Schoenrich professor of preventive medicine at Johns Hopkins University’s Sidney Kimmel Comprehensive Cancer Center, and an author of the study. He added that there were no adverse effects. But the trial did not continue for a long period or examine whether rates of cancer decreased, he said.

While the work on aflatoxin was exciting when it emerged, Timothy R. Rebbeck, a professor of cancer prevention at Dana-Farber Cancer Institute, says that, without more data, there’s not enough of a link to warrant the widespread use of chlorophyllin by consumers. “I am not sure we could expect it to have an impact on any other population, or perhaps even any other cancer,” said Dr. Rebbeck in an email interview.

Does chlorophyllin help more superficial worries, like pimples and blemishes?

A small study in the Journal of the American Academy of Dermatology examined a topical chlorophyll in conjunction with phototherapy treatments on 24 patients with acne. For one month, researchers applied this combined regimen to one side of the subjects’ face; and just the phototherapy, which was a special light-emitting device, to the other half. Although there was a reduction in the number of pimples, and severity, with both treatment protocols, there was a significant improvement with the chlorophyll combination compared to phototherapy alone.

With a small sample size, and no comparison group, there’s simply not enough data from this study or other studies to support using chlorophyll for this purpose or anti-aging, said Dr. Rajani Katta, a dermatologist and clinical assistant professor of medicine at Baylor College of Medicine.

Dr. Katta does, however, understand the allure of many people wanting to follow a celebrity’s beauty regimen. “When they are photographed, they have a whole team of makeup artists and beautiful lighting and they often look like they have beautiful skin,” said Dr. Katta. “But they might not talk about the medicated skin products, or the laser treatments they are undergoing.”

So what is chlorophyll?

Chlorophyll is the primary molecule essential for photosynthesis, absorbing the sunlight and turning it into energy for plants and blue-green algae (cyanobacteria). Specifically, it pulls in mainly red and blue light, which is why the leaves of plants appear green. A phytochemical, chlorophyll puts the green in dark leafy greens. Chlorophyll-rich superstar vegetables include raw spinach, parsley, garden cress, green beans and arugula, according to the Linus Pauling Institute at Oregon State University. Also high in chlorophyll? Wheatgrass, some blue-green algae, often consumed as the supplement spirulina, and another type of algae named chlorella.

Will drinking chlorophyll kill you?

The amount of chlorophyll in food — like a pile of salad greens — is considered safe. But limited information exists on the doses in supplements, which may be higher. Supplements are also not regulated by the Food and Drug Administration. In addition to reading the ingredients carefully, dietitians recommend looking for a third-party certification.

Still, David E. Williams, a professor of cancer prevention in the Linus Pauling Institute at Oregon State University who has researched chlorophyllin in rodents, rainbow trout and humans, said he doesn’t see a downside to supplementation. “Safety-wise, or toxicity-wise, I don’t think of any problems with chlorophyllin because it’s been used for over 50 years in humans, clinically for different things, and also as a food dye, with no evidence of harm,” Dr. Williams said.

Indeed, Ms. McIntyre of Natural Medicines said that chlorophyllin is probably safe for most people, but more research is needed. Those pregnant or nursing should avoid the substance since not enough is known. Chlorophyll and its derivative, however, may make one more sensitive to the sun.

So is chlorophyll a scam or not?

“We don’t have the evidence behind it being efficacious for any of these indications,” said Dr. Gardner. “It’s not to say that, maybe anecdotally, there are certain people who will benefit because it’s not generally a harmful thing. But I think to portray it as this anticancer, antioxidant, deodorizing, constipation-fixing, pancreatic-curing medicine is not genuine.” Indeed, there’s insufficient reliable research to rate chlorophyll for acne, hay fever, pancreatitis, as well as a treatment for skin cancer and lung cancer, according to Natural Medicines. Nor is there enough evidence that it’s an anti-inflammatory, boosts energy or cures altitude sickness.

To Ginger Hultin, a Seattle-based registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics, the whole trend reminds her of another green drink: celery juice. “We really need to look at the entire diet and not just worry about one single food as being a cure all,” she said.

Instead of buying a chlorophyll drink, Ms. Hultin suggests taking a food-first approach. “Invest in a bunch of parsley and make a tabbouleh salad,” she said. She and other dietitians recommend not just going green on the plate, but to eat the rainbow — white, purple, red, orange and yellow fruits and veggies — to maximize the variety of vitamins, minerals, antioxidants and fiber in one’s diet.

But what if, after eating all that tabbouleh, one’s breath needs a little freshening? Dr. Julius N. Manz, a dentist, says chlorophyll-related products don’t take away halitosis — they mask it, often with mint. “I can tell you for certain that brushing your teeth twice a day, going to see your dentist, those things can help with bad breath,” said Dr. Manz, who is the director of the dental hygiene program at San Juan College in Farmington, N.M. “But rinsing with chlorophyll does not.”