"Noni juice for skin" is a large search term and most of what is written under it is a stretch. The earlier version of this page was too, and it is one of the reasons this blog was rewritten.
We sell noni, and we sell into skin care. So this page has more reason than most here to overclaim, which is the reason to read it sceptically and the reason we have cut it back as far as we have.
The one real mechanism, stated at its actual size
Vitamin C is genuinely required for your body to make collagen. That is not marketing, it is biochemistry: the enzymes that stabilise collagen need vitamin C to work, which is why severe deficiency causes the skin and connective tissue problems it does.
Here is the part that gets left off. The relationship is a floor, not a dial. If you are short of vitamin C, getting enough fixes a real problem. If you already get enough, which almost everyone eating any fruit or vegetables does, more does not produce more collagen. The enzymes are not waiting on extra supply.
So "noni juice contains vitamin C, and vitamin C is needed for collagen" is two true statements that do not add up to a third one about your face.
What is actually in noni juice
Vitamin C, in amounts that vary substantially by brand, because commercial noni juice is mostly other fruit juice. Potassium, in notable amounts. A distinctive group of plant compounds called iridoids, which is where most of the research interest sits.
The earlier version of this page said a 3.5-ounce glass provides a third of your daily vitamin C. There is no basis for that figure for a blended commercial juice and we have removed it rather than replaced it, because there is no single correct number to replace it with. Check the label of whatever you buy.
The smoker studies, and why they do not say what the old page said
This is worth walking through, because it is the most common error in supplement writing and the old version of this page made it in one sentence.
Two published studies looked at noni juice in heavy smokers and reported improvements in several of the blood markers they tracked. Those studies are real.
The old article then said: if noni can do that for smokers, "imagine what this amazing fruit can do for anyone already maintaining a healthy lifestyle".
That is backwards. When a marker is far from normal, as it is in heavy smokers, there is a lot of room for it to move. When it is already normal, there is not. A result in a badly stressed group generally predicts less effect in a healthy one, not more. The same logic explains why a vitamin that transforms a deficient person does close to nothing for someone who is not.
Reading a trial result as a floor to build on rather than a ceiling to discount from is how almost every supplement claim gets inflated. We wrote about the same move in our own supplier's research in Reading the Research.
What actually affects skin from the inside
Since we have taken a lot away, here is what is left, and it is not nothing:
- Enough protein. Skin is largely protein and it is the input people underestimate most. - Enough vitamin C, which is a low bar. Any fruit and vegetable intake clears it. - Sleep and sun. Not diet, and between them they matter more than everything else on this list combined. - Enough water and not too much alcohol. Dull, correct. - Overall diet quality over months. Skin turns over slowly. Nothing you drink shows up next week.
A noni juice fits into that as a fruit juice with an unusual composition. It is a perfectly reasonable thing to drink. It is not a skin treatment and we are not going to sell it to you as one.
What you will not find here
We do not publish before and after photographs for skin, any more than we do for weight, for the reason set out on the Slenderiiz review: one person's photograph implies a typical result where none has been established.
If you want the fruit itself, that is the noni tree, and the drink is here, safety notes included.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
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