Supplement Comparisons

Which form should you actually take?

The supplement aisle sells the form, not the evidence. These 11 comparisons show what researchers say about each form, how strong the evidence is, and where sources disagree, each cited to the video and minute.

Berberine

Not enough evidence 2 sources: 2 partly

Berberine vs Metformin

Both berberine and metformin activate AMPK and lower blood glucose. That is why berberine gets called 'nature's metformin.' The label oversells it: berberine is the weaker AMPK activator,...

Creatine

Strong consensus for 11 sources: 8 positive, 2 partly, 1 neutral

Creatine Monohydrate vs Creatine HCL

Take creatine monohydrate. Expensive alternatives like HCL, ethyl ester and buffered creatine offer no added benefit.

Magnesium

Strong consensus for 8 sources: 6 positive, 2 partly

Magnesium Bisglycinate vs Magnesium Glycinate

They're the same compound. 'Bisglycinate' is the chemically precise name (one magnesium bound to two, or 'bis', glycine molecules), and 'glycinate' is the everyday shorthand for exactly...

Magnesium Glycinate vs Magnesium Citrate

Take glycinate for daily magnesium, sleep and calm. Choose citrate if you also want help with constipation; its laxative effect is the tradeoff. Both are well absorbed.

Magnesium Glycinate vs Magnesium Oxide

Take glycinate for daily magnesium, sleep and calm: it's well absorbed and gentle on the stomach. Magnesium oxide is the cheapest form but poorly absorbed; most of it passes through and...

Magnesium Glycinate vs Magnesium Threonate

Take glycinate (or malate) for your daily magnesium needs. Add threonate only if you want targeted cognitive support — but don't count it toward your daily requirement.

NMN & NAD+

Mixed +6 22 sources: 2 positive, 14 partly, 6 negative

NMN vs NAD+

NAD+ is the coenzyme your cells actually run on; NMN is a precursor you take to raise it. Oral NAD+ is a large molecule that's poorly absorbed and broken down in the gut. So it isn't...

NMN vs NR (Nicotinamide Riboside)

This is one of the most divided topics. One view says skip both, since exercise and fasting boost NAD naturally. If you do supplement, NR has more safety data, while NMN may have a...

Omega-3

Leaning for +1 17 sources: 7 positive, 10 partly

Fish Oil vs Krill Oil

Fish oil is the default for most people: high EPA, affordable, well studied. Krill oil or salmon roe is argued to be better for getting DHA into the brain, but fish oil is still the usual...

Vitamin D

Leaning for 12 sources: 6 positive, 6 partly

Vitamin D3 (Cholecalciferol) vs Vitamin D2 (Ergocalciferol)

Take D3, not D2. D3 (cholecalciferol) is the form to take, often paired with K2 for calcium metabolism. Fortified foods often use the less effective D2.

Vitamin K2

Not enough evidence 2 sources: 2 positive

Vitamin K2 (MK-7) vs Vitamin K2 (MK-4)

For everyday supplementation, MK-7 is the practical choice. Its much longer half-life means a single daily dose keeps blood levels steady, and it's the form in nearly every D3+K2...

Each badge is the verdict on the supplement overall, worked out from every counted mention.

positive partly neutral negative Each researcher and each study counts once per claim, however often they come up.

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