Benefits
What is actually in it
CompleteGreens is a base powder of concentrated fruit, vegetable, herb and spice extracts with added L-ergothioneine. It is sold to supplement companies, who add flavouring and their own label, so a shopper meets it under another brand's name. Nothing in it is exclusive to this blend: the same kinds of botanical powders and the same L-ergothioneine are sold in many greens products.
Same blend as MitoGreens, at a bigger serving
CompleteGreens uses NNB's MitoGreens blend, scaled up from the 100 mg ingredient dose to a scoopable powder. MitoGreens has no published human trial of its own, so the larger serving inherits a formulation, not an evidence base. A PubMed search for MitoGreens returns nothing.
L-ergothioneine, an antioxidant the body actively absorbs
L-ergothioneine is taken up from food by a dedicated transporter, OCTN1 (SLC22A4), and accumulates in mitochondria and in white blood cells. It scavenges a wide range of reactive oxygen and nitrogen species in laboratory systems. No human study has compared it head to head against glutathione, vitamin C or CoQ10. In people the antioxidant readings are thin and mixed: giving pure ergothioneine to healthy volunteers produced downward trends in markers of oxidative damage that were mostly not statistically significant, and total antioxidant capacity measured after an ergothioneine-rich mushroom meal went down rather than up.
A multi-botanical blend of undisclosed composition
NNB describes the blend as 29 superfood ingredients on one page and over 30 on another, and does not publish the full ingredient list with amounts. Without per-botanical amounts there is no way to check whether any single plant is present at a level that has been studied, and a long ingredient list is not itself evidence of anything.
What the evidence does not show
No trial has tested CompleteGreens in people. PubMed searches for CompleteGreens, MitoGreens and MitoPrime each return no studies, and NNB's own product page cites none. Everything claimed for the product rests on research into isolated compounds at set doses, which may bear no relation to what a scoop of a multi-botanical powder delivers.
Immune effects have not been shown
L-ergothioneine concentrates inside immune cells, but that is a mechanism, not a result. In the closest human test, 5 g a day of an ergothioneine-rich mushroom powder for eight weeks in 85 adults aged 60 and over raised blood ergothioneine yet did not significantly improve influenza vaccination antibody responses, white cell counts, quality of life, or the rate of influenza-like illness. One antibody measure (IgM) rose more in the mushroom group than in the placebo group but missed statistical significance.
Practical points before you buy
CompleteGreens reaches shoppers inside a finished product sold under someone else's brand, and that brand decides the scoop size and how much of the base it contains. Check the finished label for the L-ergothioneine amount, because NNB does not publish it, and treat a greens powder as a convenience rather than a replacement for eating vegetables.
Mechanism of action
L-ergothioneine uptake through the OCTN1 transporter
L-ergothioneine is absorbed and retained through the OCTN1 (SLC22A4) transporter, is not rapidly metabolised or excreted, and accumulates in mitochondria and immune cells. In laboratory systems it scavenges reactive oxygen and nitrogen species and chelates metals. No human study has ranked it against glutathione, vitamin C or CoQ10.
Several polyphenol classes, amounts not published
Concentrated fruit, vegetable and herb powders supply several polyphenol classes, including flavonoids, anthocyanins, proanthocyanidins and phenolic acids, which differ in the species they react with and the tissues they reach. Because NNB does not publish per-botanical amounts, there is no way to say what quantity of any of these a serving contains.
What ergothioneine and quercetin do to mitochondria in the laboratory
Ergothioneine accumulates inside mitochondria, and quercetin activates AMPK and PGC-1 alpha in cell and animal work. Whether either happens to a useful degree in a person taking a greens powder has not been tested, and mitochondrial function has not been measured in anyone taking this blend.
Immune cell ergothioneine accumulation
Ergothioneine accumulates in neutrophils, monocytes and lymphocytes via the OCTN1 transporter, which is why an immune role has been proposed. It remains a proposal: in a placebo-controlled trial in adults aged 60 and over, an ergothioneine-rich food that clearly raised blood ergothioneine did not change vaccination antibody responses, leukocyte counts or rates of influenza-like illness.
How plant polyphenols are thought to work
Plant polyphenols act through several routes in cell and animal work, including direct radical scavenging, dampening of NF-kB signalling and activation of the Nrf2 pathway. None of this has been measured in a person taking this blend, and NNB does not publish how much of any individual botanical a serving contains.
Clinical trials
PubMed searches for CompleteGreens, MitoGreens and MitoPrime return no studies, and NNB's own product page cites none. What follows describes research on individual compounds, not on this blend.
None. No human study of this product exists.
Nothing has been measured in anyone taking CompleteGreens. The isolated compounds in the references were given on their own at set doses. The human results closest to this page's claims are not positive: an ergothioneine-rich food did not improve immune responses in older adults, and the human antioxidant readings for ergothioneine are either non-significant trends or, in one acute mushroom meal study, a fall in total antioxidant capacity.
General population research on diets rich in fruit, vegetables and herbs. This is background about eating whole foods, not a study of a concentrated powder, and it is not a trial.
Not a study. General dietary research in the population at large.
Diets high in fruit and vegetables track with better health markers in population studies. Those findings come from whole foods eaten as meals, and they do not carry over to a scoop of concentrated powder whose per-botanical amounts are not published. Nothing here was measured in anyone taking CompleteGreens.
NNB Nutrition's own description of its ingredient range and manufacturing approach. It contains no study, no participants and no measurements.
Not a study. Supplier marketing material.
This is information about the manufacturer, not about what CompleteGreens does in a person. It should carry no weight in deciding whether to take the product.