Chlorophyll / Chlorophyllin

The green pigment in plants. Its best-supported trick is binding certain toxins in the gut before you absorb them.

Mechanisms, studies and evidence grades for each claim above.

Chlorophyll vs. chlorophyllin

Chlorophyll is the fat-soluble green pigment in plants. Chlorophyllin is a semisynthetic, water-soluble mixture derived from it (usually as sodium copper chlorophyllin), used as a food colorant and over-the-counter supplement. Almost all human data come from chlorophyllin; one small study suggests natural chlorophyll behaves similarly.² It is not an essential nutrient and has no deficiency syndrome.

Blocks absorption of a liver carcinogen

The mechanism is simple: chlorophyll's flat ring structure forms tight complexes with other flat molecules in the gut — including aflatoxin B1, a mold toxin found on poorly stored grains, corn and peanuts and a major cause of liver cancer in high-exposure regions — so less of the carcinogen is absorbed. This worked consistently in trout and rat models.¹

The key human trial was run in Qidong, China, where liver-cancer risk is high partly from dietary aflatoxin. 180 healthy adults took 100 mg chlorophyllin or placebo three times a day with meals for four months. Chlorophyllin cut the median urinary level of aflatoxin-DNA adducts — a biomarker of the dose that actually reached and damaged DNA, and one associated with liver-cancer risk — by 55% (p=0.036), with no adverse events.¹ A later small crossover study in U.S. volunteers given a trace radiolabelled dose found that both chlorophyll and chlorophyllin taken alongside it reduced aflatoxin absorption.²

What this does not show: a reduction in actual cancer incidence (the trial measured a biomarker for four months), or any benefit in low-exposure populations eating well-stored food. It's the most concrete support for a food-matrix idea — greens eaten with a meal may reduce uptake of some flat, ring-shaped carcinogens — not for chlorophyll water as a general "detox". (Moderate for the biomarker effect; Inferred for cancer prevention)

May reduce body odor

Chlorophyllin has been sold as an internal deodorant for decades, mostly on anecdote. The clearest data are in trimethylaminuria ("fish odor syndrome"), a genetic disorder in which the body can't convert fishy-smelling trimethylamine to its odorless form. In seven Japanese patients, copper chlorophyllin (180 mg/day for 3 weeks) normalized the ratio of urinary trimethylamine to its odorless metabolite, with the effect lasting several weeks — longer than activated charcoal.³ That is a tiny, uncontrolled study in a rare condition; it doesn't establish an effect on ordinary body odor. (Early — small case series)

Practical notes

For most people the food-first approach is the defensible one: dark leafy greens supply chlorophyll alongside nitrate, folate and magnesium, all of which have better evidence behind them. Chlorophyllin supplements are well tolerated at trial doses; the common side effect is green discoloration of stool.

Top foods

• Spinach
• Kale
• Arugula
• Broccoli
• Brussels sprouts

References