The evidence reference

Ingredients.
Graded, not praised.

One page per ingredient, with every claimed benefit graded separately against published criteria. Grades are assigned per claim because evidence strength varies by use — an ingredient can be well supported for one thing and unsupported for another.

Amino acidBModerate evidence

L-theanine

L-theanine is an amino acid found almost exclusively in tea. The best-supported use is short-term: taken with caffeine, it reliably changes how the caffeine feels, reducing jitteriness while attention improves.

3 graded claims
Soluble fibreDWeak evidence

Glucomannan

Glucomannan is a soluble fibre from konjac root that absorbs water and forms a gel, which is why it is sold for appetite control and weight loss. The NIH Office of Dietary Supplements concludes it has little to no effect on weight loss.

3 graded claims
Fat-soluble vitaminAStrong evidence

Vitamin D3

Vitamin D3 (cholecalciferol) is the form of vitamin D your skin makes from sunlight. The evidence for correcting a documented deficiency is strong and uncontroversial.

4 graded claims
Soluble fibreAStrong evidence

Psyllium husk

Psyllium husk is a soluble fibre from the seeds of Plantago ovata. It is one of the few supplement ingredients carrying an FDA-authorised health claim: soluble fibre from psyllium may reduce the risk of heart disease when eaten as part of a low-fat diet.

4 graded claims
Botanical extractCLimited evidence

Green tea extract

Green tea extract is a concentrated preparation of the catechins in green tea, principally EGCG. The NIH states it might help with a small amount of weight loss — an effect too small to matter much in practice.

4 graded claims
Fatty acidBModerate evidence

Omega-3 (EPA and DHA)

EPA and DHA are the long-chain omega-3 fatty acids found in oily fish. The evidence that high doses lower triglycerides is strong and clinically established.

5 graded claims

Why grade by claim

A single letter for a whole ingredient hides the distinction that actually matters. Glucomannan is a reasonable fibre with acceptable support for regularity and effectively none for weight loss — the use it is almost always sold for. Averaging those into one grade would reassure exactly the reader who needs warning. So every claimed benefit gets its own grade, and the criteria are published rather than asserted.

A site where nothing ever scores below B is not being rigorous, it is being polite. Some of these grades are deliberately low.