Most greens powders list between twenty and fifty ingredients. Four or five appear in amounts anyone has studied. The rest — ginkgo, milk thistle, licorice root, bilberry, bee pollen, royal jelly and the other small-dose botanicals — sit on the label at 10 to 150 mg, often a tenth or a twentieth of the amounts used in the trials their reputations rest on.
This guide covers that long tail: what each is, what human research found and did not find, and which carry warnings that matter regardless of dose. The ingredients present in meaningful quantities have their own guides — spirulina, chlorella, camu camu and the cereal grasses.
Why a blend carries a long tail of small-dose botanicals
A serving of greens powder weighs about 8 to 10 grams. Spirulina, chlorella and the grass powders take most of that. Whatever remains is divided among everything else on the label.
Divide two grams among thirty ingredients and the arithmetic is unforgiving. Some of those ingredients earn their place technically: lecithin emulsifies, vitamin E slows oxidation, beet and berry powders supply color. Those are real jobs, but they are not health benefits, and a long ingredient list is not the same thing as a potent one.
| Ingredient | Typical amount in a blend | Amount used in human trials |
|---|---|---|
| Milk thistle | 30–60 mg | 420 mg silymarin, three times a day |
| Bilberry extract | 5–15 mg | 160–480 mg standardized extract daily |
| Ginkgo leaf extract | rarely disclosed | 120–240 mg standardized extract daily |
| Beet juice powder | 100–500 mg | 6.2–12.8 mmol nitrate, roughly 70–250 mL of juice |
| Phosphatidylcholine | ~125 mg, about 16 mg of choline | choline adequate intake is 425–550 mg daily |
| Licorice root | 30–60 mg | 100 mg glycyrrhizin daily is a ceiling, not a target |
Two conclusions follow. These amounts are almost certainly too small to reproduce what the studies measured. They are also, with the exceptions noted below, too small to do harm.
Ginkgo biloba and milk thistle
These are the two best-studied botanicals here, and the two whose reputations have aged worst. Ginkgo leaf extract is standardized to roughly 24 percent flavone glycosides and 6 percent terpene lactones. The Ginkgo Evaluation of Memory study randomized 3,069 adults aged 75 and over to 240 mg daily or placebo for a median of about six years, and found no difference between groups in the rate at which participants developed dementia or Alzheimer’s disease. NCCIH’s current position on ginkgo is that no conclusive evidence supports it for any health condition.
Ginkgo’s safety note stands independently of that. It has antiplatelet activity, spontaneous bleeding has been reported, and it does not belong alongside warfarin, other anticoagulants or antiplatelet drugs. It has also been associated with seizures in people predisposed to them. Anyone on those drugs, or facing surgery, should raise it with their prescriber.
Milk thistle’s active fraction is silymarin. In a 2012 randomized trial in JAMA, 154 people with chronic hepatitis C took silymarin three times daily for 24 weeks at doses far above supplement levels, and serum ALT and viral load did not differ from placebo. NCCIH notes that its own funded trials in hepatitis C and in nonalcoholic steatohepatitis showed no benefit either. It is well tolerated, but it modulates UGT enzymes and has documented drug interactions worth checking against a medication list. The older language around it — detoxifying, cleansing the blood — describes nothing the liver does not already do.
Licorice root, the one with a real ceiling
Glycyrrhizin, licorice’s principal compound, blocks the enzyme that clears cortisol from mineralocorticoid receptors. The result is sodium retention and potassium loss, which is why New Zealand’s Medsafe and European regulators recommend a ceiling of 100 mg of glycyrrhizin a day. Reported consequences of exceeding it include low potassium, irregular heart rhythm, edema, muscle weakness and raised blood pressure. Licorice raises blood pressure. It does not lower it, and any source claiming otherwise should be discarded.
At 30 to 60 mg of root standardized to about 5 percent glycyrrhizin, a blend supplies roughly 2 to 3 mg, well inside that ceiling. The catch is that licorice is also in teas, candy, lozenges and Chinese herbal formulas, and exposure stacks across all of them. People with high blood pressure, on potassium-depleting diuretics or digoxin, or pregnant, have reason to track total licorice intake rather than any single source. Deglycyrrhizinated licorice, labeled DGL, has the compound removed.
The pigment ingredients: bilberry, beet juice and dunaliella
Bilberry is a European relative of the blueberry, and the source of a durable myth. The story that RAF pilots ate bilberry jam to sharpen night vision was wartime cover for radar. Canter and Ernst’s 2004 review in Survey of Ophthalmology examined twelve placebo-controlled trials of bilberry anthocyanosides for night vision; the four most recent and most rigorous found no effect, and better methodology tracked with negative results. As a concentrated extract, bilberry has antiplatelet activity in laboratory work, which puts it in the same conversation as ginkgo for anyone on anticoagulants. As a berry, it is a berry.
Red beet juice has the best-supported mechanism here. Beets are high in inorganic nitrate, which the body converts through nitrite to nitric oxide. A 2022 meta-analysis of seven randomized trials covering 218 participants reported that beetroot juice supplying 6.2 to 12.8 mmol of nitrate was associated with a mean systolic reduction of 4.95 mmHg, with no statistically significant diastolic change. That is roughly 70 to 250 mL of concentrated juice. Freeze-dried beet powder in a blend does not approach it, and nitrate content varies widely with soil and cultivar. Two older claims are wrong: betaine is not derived from betalain pigments, and neither performs “colon cleansing.”
Dunaliella salina is a salt-tolerant microalga grown for mixed carotenoids, mostly beta-carotene with alpha-carotene, zeaxanthin and lutein. It is a reasonable carotenoid source, not the most nutrient-dense food on earth, and the repeated “72 trace minerals” is not a real figure. The caution concerns beta-carotene at supplemental doses. The NIH Office of Dietary Supplements summarizes the ATBC trial, where 20 mg a day was associated with 18 percent higher lung cancer incidence among male smokers, and a second trial, CARET, that was stopped early for the same signal. The Food and Nutrition Board advises against beta-carotene supplements for the general population outside of correcting deficiency.
The bee products: pollen and royal jelly
These are the exception to the “too small to matter” rule, because allergic reactions do not scale down neatly with dose.
Bee pollen is multifloral pollen collected at the hive entrance, and its makeup changes with whatever the bees were visiting. Human evidence for the claims made about it is thin, and the old claim that eating it desensitizes seasonal pollen allergy points the wrong way. A 2025 review of allergic risks from bee products catalogs anaphylaxis case reports after ingestion, including exercise-augmented episodes and cases in children, concentrated among people already allergic to airborne pollen.
Royal jelly is better documented, and the documentation is mostly about harm. Memorial Sloan Kettering’s About Herbs entry records anaphylaxis, asthma including fatal cases and hemorrhagic colitis, identifies major royal jelly protein 3 as the principal allergen, and cites a meta-analysis that found no improvement in glucose levels. Specific IgE to royal jelly has been detected in a substantial minority of adults with asthma and of patients with atopic dermatitis. Anyone with asthma, atopic dermatitis, allergic rhinitis or a known bee allergy should avoid royal jelly and bee pollen entirely, at any amount, including traces in a blend.
Royalactin, the compound royal jelly marketing leans on, is a protein rather than an amino acid, and its documented effect is on bee larvae.
Lecithin, vitamin E, soy sprouts and dates
Soy lecithin is an emulsifier that keeps powder dispersing instead of clumping. Its phosphatidylcholine is often converted into a choline claim, and the conversion is usually done wrong: phosphatidylcholine is only about 13 percent choline by weight, so 125 mg supplies roughly 16 mg of choline against an adequate intake of 425 mg for women and 550 mg for men. ODS also cites a 2015 systematic review that found no clear cognitive improvement from choline supplements in healthy adults, and a Cochrane review of twelve randomized trials that found no clear clinical benefit of lecithin in dementia.
Vitamin E is usually there as a natural antioxidant protecting the fats in the powder from going rancid. Natural d-alpha-tocopherol is roughly twice as active by weight as the synthetic dl- form, not five times as older copy claimed. The Daily Value is now 15 mg and the upper intake level is 1,000 mg. High-dose supplementation has a poor trial record — SELECT reported 17 percent higher prostate cancer incidence on 400 IU daily — and blend amounts are nowhere near it. This is a preservative doing a preservative’s job.
Soy sprouts supply isoflavones, principally genistein and daidzein. Calling them “anti-estrogenic compounds” is wrong; they behave as selective estrogen receptor modulators, agonists in some tissues and antagonists in others. People taking tamoxifen or aromatase inhibitors, and people with thyroid conditions, have reason to discuss isoflavone supplements with their clinician. The claim that sprouts deliver active superoxide dismutase does not survive digestion — enzymes are proteins, broken down like any other protein.
Dates are a sweetener and binder, more often in bars than powders — sugar, with useful fiber, potassium and polyphenols attached, not complex carbohydrates.
How to judge whether a botanical on a label is doing anything
- Look for a number. An ingredient listed without milligrams is a decoration. A proprietary blend giving one total for twenty ingredients is saying the individual amounts are not worth printing.
- Compare that number to the studied dose. Under a tenth, assume nothing. This one check settles most labels.
- Look for the standardization, not the plant. “Ginkgo leaf” and “ginkgo leaf extract standardized to 24% flavone glycosides” are different products at different prices.
- Distrust “equivalent to.” Claims that a powder equals a larger weight of fresh plant usually describe water removal.
- Count the ingredients. Serving weight is fixed. Everything added past about fifteen makes everything else smaller.
- Separate function from benefit. Emulsifiers, preservatives, sweeteners and colors earn their place without doing anything for the drinker.
- Check allergy separately from dose. Interactions scale with amount. Allergic reactions do not.
Common questions
Is a greens powder with 50 ingredients better than one with 15?
Usually the opposite, for the arithmetic reason above. A fixed scoop split fifty ways gives less of everything. A shorter list with disclosed amounts of a few well-studied ingredients is more defensible.
If the doses are too low to do anything, why include them?
Some earn their place functionally, as emulsifiers, preservatives, colors or sweeteners. Others add small amounts of polyphenols and carotenoids to a varied diet, which is modest but not nothing. Some are there because the label sells better with them.
Can I take these botanicals separately at the doses used in research?
For some, yes, and that is the honest route if a specific botanical is the goal. It also means taking on the full safety profile — the ginkgo bleeding risk, the licorice ceiling, the interaction checks — that trace amounts do not.
Which of these should someone avoid outright?
Bee pollen and royal jelly for anyone with asthma, atopic dermatitis, allergic rhinitis or bee allergy. Ginkgo and concentrated bilberry extract for anyone on anticoagulants or antiplatelet drugs. Licorice for anyone with high blood pressure or on potassium-depleting diuretics. Beta-carotene supplements for current and former smokers.
What to take from this
The long tail of botanicals in a greens blend is mostly a list of things present in amounts too small to reproduce the research attached to their names. The exceptions run toward caution: bee products can cause severe allergic reactions at any dose, and ginkgo, licorice and carotenoids each carry interactions worth checking against a medication list.
What a greens powder can reasonably offer is a convenient source of a few well-studied whole-food ingredients, with disclosed amounts and verifiable sourcing. That is what we try to write honestly about at Greens Plus.
About the Author
