Fireblood Blog — Supplement Science & Ingredient Guides

Colourful supplement pills spilling from a white bottle onto a dark surface
The most transparent multivitamin: how to tell
Transparency isn't a word on the label. It's named forms, exact doses, no proprietary blends and a published COA. Here's how to check in 90 seconds. Read more...
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Vitamin D2 vs D3: which form actually raises your levels
Vitamin D3 raises and holds your blood levels better than D2. If a label just says vitamin D, it is usually the weaker form. Here is the difference. Read more...
Whole grains and rice on a dark surface, a dietary source of vitamin B1 thiamine
Vitamin B1 deficiency symptoms: the early signs most men miss
Vitamin B1 (thiamine) deficiency causes fatigue, brain fog and tingling hands and feet. The early signs, who is at risk, and how to fix the gap. Read more...
Multivitamin pills spilling from a white bottle on a dark surface
Best multivitamin for men: 7 markers to check
The best multivitamin for men uses bioavailable forms at full doses and covers what men run low on. Here are the 7 markers that prove it. Read more...
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The best time to take vitamins, sorted by type
Fat-soluble vitamins absorb best with a fatty meal. Water-soluble ones work any time. Here's when to take each vitamin and mineral for best absorption. Read more...
Sliced cooked steak and vegetables on a dark surface, a complete source of essential amino acids
Does your multivitamin have amino acids? Almost none do
Almost no multivitamin contains amino acids. Here is why, which nine are essential, and what a complete daily profile looks like. Read more...
White magnesium powder scattered on a black surface
Magnesium bisglycinate vs glycinate: same thing?
Magnesium bisglycinate and glycinate are the same molecule. Here's why the names differ and the buffered-oxide trap to watch for. Read more...
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Selenium benefits for men: the 5 things it does
Selenium runs your thyroid, antioxidant defence and sperm production. What it does for men, the right dose, and why more is not better. Read more...
Dark x-ray of a human hand showing the bones against a black background
Bone health for men: the 4 nutrients that matter
Calcium alone doesn't build bone. Vitamin D3, K2, magnesium and manganese do the real work for men. The forms, the doses, and what most diets miss. Read more...
Assorted supplement pills spilling from a white bottle on a dark surface
Does biotin help hair growth? Only if you're deficient
Biotin only grows hair if you're deficient, and deficiency is rare. The evidence, the megadose myth, and the dose that's actually enough. Read more...
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Retinyl palmitate vs beta-carotene: which vitamin A form actually works
Beta-carotene only becomes vitamin A if your genes convert it well, and up to 45% of people don't. Retinyl palmitate skips that lottery. Read more...
Opened supplement capsule spilling powder onto a dark surface
MSM benefits: what the research shows and what 500mg actually does
MSM is studied for joints and recovery at 3g a day. Here is what the research shows, and what the 500mg in a daily multivitamin actually does. Read more...