What Is Chlorophyll?
Chlorophyll is a pigment in plants that makes them look green. It has been a popular supplement since the 1960s. But so far, there’s no clear proof that it has health benefits. It’s also a key ingredient in photosynthesis, the process by which plants convert sunlight into different forms of energy and, ultimately, into the oxygen we breathe. Simply put, chlorophyll sustains life.
While it does perform such important work, there’s no clear proof that taking it in supplement form offers any health benefits. Nevertheless, chlorophyll has been a popular supplement since the 1960s.
One thing to keep in mind: “The chlorophyll in supplements is actually chlorophyllin,” says Stephanie Schiff, a registered dietitian at Northwell Health’s Huntington Hospital in Huntington, NY.
Chlorophyllin is a water-soluble chemical derived from chlorophyll, which Schiff says is easier for the body to absorb. It’s mixed in a lab to create a shelf-stable mixture containing copper and sodium.
Benefits of Chlorophyll
There’s very little research about chlorophyll as a treatment for anything, and there is no solid evidence of health benefits. And most of the studies on chlorophyll have been done on animals and may not apply to us.
Chlorophyll benefits for women
Beth Czerwony, a registered dietitian with the Cleveland Clinic Center for Human Nutrition in Cleveland, OH, says chlorophyll has no specific benefits for women or people assigned female at birth (AFAB).
“However,” she says, “it is not recommended for women who are breastfeeding.”
Schiff agrees and extends that to include avoiding chlorophyll supplements if you are pregnant. Why? “There hasn’t been enough research on their safety,” says Schiff.
As with any supplement or over-the-counter drug, you should check with your doctor before you take chlorophyll.
There’s no standard dose for chlorophyll. Ask your doctor for advice.
Chlorophyll benefits for men
There are no chlorophyll benefits specific to men or people assigned male at birth (AMAB). Schiff points out that some chlorophyll supplements claim that they improve the taste of semen.
Some lab tests suggest chlorophyll could help block some cancer-causing chemicals. But we don't know if it would have any benefit against cancer in people. Some examples:
- Two mouse studies suggest that chlorophyll may protect against skin cancer.
- Studies found that chlorophyll may offer protection from liver, colon, and stomach cancer, at least in rainbow trout and rats.
- Lab studies suggest that chlorophyll may slow the growth of pancreatic cancer and lung cancer.
- In a human study, researchers found that chlorophyll helped rid the body of aflatoxin, a type of highly poisonous mold that can contaminate food and cause liver cancer.
Does this research indicate that chlorophyll has cancer-fighting properties? No, says Czerwony.
“Research studies have been mostly animal studies, and the few exceptions have been too small and/or of poor quality to offer any real evidence,” says Czerwony. “Anything [that claims] to reduce the risk of cancer should be viewed with caution.”
On the other hand, she points out, studies do show that eating fruits and vegetables — all of which naturally contain chlorophyll — does reduce cancer risk.
Schiff says that taking chlorophyll supplements while receiving cancer care is likely safe. She would have concerns if people took chlorophyll — or any supplement — instead of standard cancer treatments.
“If chlorophyll is used in addition to standard treatments, and with the approval of a person’s doctor, then I don’t think it’s harmful,” Schiff says.
Chlorophyll for bad breath
Claims that chlorophyll can help reduce bad breath have been around since at least 1950. They appeared following the publication of a study in which 12 people drank onion juice. Their breath, the study claims, improved after taking a dose of liquid chlorophyll. Chlorophyll tablets also freshened breath, but less so.
Does it really work? “There isn’t much scientific evidence to suggest that chlorophyll supplements can help with bad breath,” says Schiff.
Chlorophyll for body odor
Claims about chlorophyll’s ability to improve body odor also date back many decades, starting with a 1947 study. The authors wrote that chlorophyll has antibacterial properties that aid wound healing as well as reduce the odor that comes with infection. Chlorophyll’s alleged ability to make you smell better has been touted ever since, despite a lack of evidence.
“Reducing body odor is a claim that some chlorophyll supplements carry, but there hasn’t been enough research to determine whether or not this is true,” says Schiff.
Chlorophyll and constipation
Schiff says that chlorophyll is commonly used for constipation, but she says that most of the evidence that supports its use is unscientific. If you’re considering it, she offers a warning: “It can loosen stool to the point where it can potentially cause diarrhea,” she says.
Chlorophyll Sources
You can get chlorophyll from many foods as well as from supplements (in its modified form, called chlorophyllin), which comes in liquid and pill form.
Chlorophyll from plants
Chlorophyll is found in all leafy plants. Levels are especially high in dark-green leafy vegetables, such as spinach, parsley, and kale.
Other food sources of chlorophyll include:
- Cress (also called garden cress)
- Green beans
- Arugula
- Leeks
- Endive
- Sugar peas
- Chinese cabbage
- Asparagus
- Arugula
- Broccoli
- Wheatgrass
“If you eat these foods, you’ll get other nutrients and fiber — which can also help with digestion, weight loss and reducing inflammation — as well,” says Schiff, who stresses that food is the best way to get chlorophyll.
“Often beneficial plant compounds that are extracted from foods and made into supplements don’t work as well as they would if you had eaten actual food,” she says.
That, she continues, is because the vitamins, minerals, and other nutrients in food offer more benefits when they work together compared to when a particular compound, such as chlorophyll, is isolated and acting on its own in supplement form.
Liquid chlorophyll
Some chlorophyll supplements come in a liquid form. “Liquid chlorophyll is typically preferred by people who want to put drops into their drinks or smoothies,” says Schiff.
Czerwony says liquid supplements may be absorbed by your body faster than chlorophyll pills.
Chlorophyll pills
Chlorophyll supplements are also available as tablets or capsules. These, says Schiff, tend to be more convenient and less messy. However, it may take longer for your body to absorb them compared to liquid chlorophyll.
Chlorophyll Side Effects and Risks
Chlorophyll appears to be safe when taken in moderation, but it does have some potential side effects. Tell your doctor about any supplements you’re taking, even if they’re natural. That way, your doctor can check on any potential side effects or interactions with medications.
Chlorophyll side effects
Several side effects may occur when taking chlorophyll. These include:
Liquid chlorophyll side effects
Because your body may absorb liquid chlorophyll more quickly, any side effects you experience may develop sooner and last longer than those of chlorophyll supplements in pill form, says Czerwony.
Chlorophyll risks
Taking chlorophyll may make your skin more sensitive to sunlight, increasing your risk of sunburn. It’s not known whether it’s safe to take chlorophyll supplements while pregnant or breastfeeding. Both Czerwony and Schiff advise against it.
Chlorophyll medication interactions
Just because a supplement is plant-based, it does not mean it’s safe to mix with your medications, says Czerwony. “If you are taking the following medications, it is strongly recommended not to start taking chlorophyll supplements,” she says.
- Some antibiotics
- Some acne medications
- Some antidepressants
- Diuretics (also called water pills)
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
Schiff says that you should not take chlorophyll if you currently take methotrexate, a drug used to treat rheumatoid arthritis, psoriasis, and some cancers.
“Methotrexate may stay in the body longer than desired if used with chlorophyll supplements,” she explains.
Something to keep in mind: The U.S. FDA does not regulate dietary supplements as drugs. Unlike drug manufacturers, the makers of supplements don’t have to show their products are safe or effective before selling them on the market.
Czerwony points out that the potency of chlorophyll supplements can vary from batch to batch, so you never know exactly how much you’re getting.
“So,” she says, “I would recommend following a diet high in antioxidants, which include plenty of fruits and vegetables (primarily those that are deep green in color) and not rely on supplements.”
Takeaways
Chlorophyll supplements may have few risks, but they have no proven health benefits, whether you take them in liquid or pill form.
They should not replace medications proven to treat diseases such as cancer. Talk to your doctor before you take chlorophyll, as it can interact with certain medications.
Your best bet is to eat fruits and vegetables, especially green ones, if you want a chlorophyll fix.
Chlorophyll FAQs
Does chlorophyll make you poop?
It can. One possible benefit may be constipation relief, but there’s not enough research to be sure. However, chlorophyll can also cause diarrhea.
How long does chlorophyll take to work?
There’s not enough research to say that chlorophyll has any real benefits or how long you must wait to see them. Schiff says that some anecdotal evidence suggests chlorophyll may improve constipation in a few days. However, she warns that there’s no way to tell if it’s the chlorophyll or the placebo effect — your belief that the supplement will help — that’s making you feel better.
What should I avoid while taking chlorophyll?
Your doctor is the best person to answer this question, but some medications are known to interact with chlorophyll. These include:
- Certain antibiotics
- Some acne medications
- Certain antidepressants
- Diuretics
- Nonsteroidal anti-inflammatory drugs (NSAIDs)