Sodium copper chlorophyllin has a strong safety profile. It is not toxic, not mutagenic, and is approved for use in both food coloring and over-the-counter supplements. The joint WHO/FAO expert committee on food additives (JECFA) has set an acceptable daily intake of up to 15 mg per kilogram of body weight, which for a 150-pound adult works out to roughly 1,000 mg per day. Most supplements contain far less than that.
What It Is and How It’s Regulated
Sodium copper chlorophyllin is a water-soluble compound derived from chlorophyll, the pigment that makes plants green. During manufacturing, the magnesium atom at the center of natural chlorophyll is replaced with copper, which makes the color more stable and vibrant. This is the form found in most “liquid chlorophyll” drops and chlorophyll supplement capsules.
In the United States, the FDA permits sodium copper chlorophyllin as a color additive in citrus-based dry beverage mixes at concentrations up to 0.2 percent. It is exempt from batch certification, meaning the FDA does not consider it a public health concern requiring lot-by-lot testing. Separately, the FDA allows over-the-counter use of chlorophyllin copper complex as an internal deodorant at doses up to 300 mg per day. So the compound occupies a somewhat unusual space: it’s both a food-grade colorant and a recognized OTC product.
Toxicity and DNA Safety
Standard laboratory testing (the Ames test, which screens compounds for the ability to cause genetic mutations) found that chlorophyllin was neither mutagenic nor toxic to bacterial cells at the concentrations tested. Researchers confirmed this wasn’t simply because the compound was killing mutant cells before they could be counted. Recovery of test bacteria was approximately 100 percent whether chlorophyllin was present or not. In fact, chlorophyllin acted as a potent antimutagen, reducing the DNA-damaging effects of various environmental and dietary complex mixtures rather than adding to them.
This antimutagen property is one reason chlorophyllin has attracted interest in cancer prevention research, though the practical relevance for supplement users remains unclear.
Common Side Effects
The most noticeable side effect is cosmetic: green discoloration of urine and stool. This is harmless and simply reflects the intense pigment passing through your system. Some people also notice a yellow or black discoloration of the tongue. Occasional reports of diarrhea exist, but gastrointestinal upset appears to be uncommon at typical supplement doses.
If you apply chlorophyllin topically (some wound care products contain it), mild burning or itching at the application site has been reported in some cases.
One side effect worth knowing about: oral chlorophyllin can cause false positive results on guaiac-based stool tests, the kind used to screen for hidden blood in the stool. If you’re scheduled for a fecal occult blood test, let your provider know you’re taking chlorophyllin so the results aren’t misinterpreted.
How Much Is Considered Safe
The JECFA acceptable daily intake of 0 to 15 mg per kilogram of body weight provides a generous ceiling. For context, most chlorophyll supplements on the market deliver between 100 and 300 mg per day, and the FDA’s OTC deodorant limit is 300 mg daily. A 70-kg (154-pound) person would reach the JECFA upper limit at 1,050 mg per day, well above what any standard supplement provides.
That said, “acceptable daily intake” values are designed to represent lifelong daily consumption without appreciable health risk. They already include built-in safety margins. Staying within the typical supplement range of 100 to 300 mg daily keeps you well within established safety boundaries.
The Copper Question
Because sodium copper chlorophyllin contains a copper atom in its molecular structure, some people worry about copper accumulation. The copper in this compound is tightly bound within the chlorophyll ring, which limits how much free copper your body absorbs during digestion. At standard supplement doses, the copper contribution is small relative to what you’d get from foods like shellfish, nuts, or chocolate. People with Wilson’s disease or other conditions involving impaired copper metabolism should be cautious with any supplemental copper source, but for the general population this is not a practical concern at normal doses.
Pregnancy and Breastfeeding
There is very little direct safety data on sodium copper chlorophyllin use during pregnancy or breastfeeding. No specific contraindications have been identified in the published literature, but the absence of dedicated studies in these populations means the evidence is simply incomplete rather than reassuring. This is common for dietary supplements in general, not a red flag specific to chlorophyllin.