This Source Naturals capsule is built around immune support, delivering 125mg of **Transfer Factor Complex** — a fractionated colostrum extract. At one capsule a day you're getting the low end of the range these fractions are typically labeled at (100–600mg); the label's allowance of up to 5 capsules during physiological stress would take you to 625mg.
What matters more than the dose is the evidence: there's no clinical trial establishing a therapeutic amount for transfer-factor fractions, and the core idea you're paying for — that these concentrated fractions transfer immunity better than whole colostrum — hasn't held up under independent research. That weak evidence base is why this scores low, not the milligrams.
So if immune support is your goal, you're buying a proprietary fraction whose active components aren't standardized or independently validated. And skip it entirely if you're dairy-allergic or lactose-intolerant, since colostrum contains both.
BioStacks
Ingredients (1)
Transfer Factor Complex
100%Dose
125 mg
Target
100–600 mg
Form
—
Other Ingredients (4)
MaltodextrinBinder
Spikes blood sugar faster than table sugar (glycemic index 85–105). Research links it to gut bacteria changes that may promote intestinal inflammation (Nickerson et al. 2015). Used as a cheap filler — adds nothing beneficial.
Magnesium StearateLubricant
A salt of stearic acid used as a lubricant in tablet and capsule production
Silicon DioxideAnti-caking
Fine silica powder used to prevent clumping
Microcrystalline CelluloseBinder
Plant-derived cellulose used as a binder and filler in supplements
How to Take It
Take it anytime
Timing doesn't matter for this one — taking it consistently does.
With or without food
On the label
1 capsule per day with water for general well-being. During times of physiological stress 1 capsule may be taken up to 5 times of per day. Take on an empty stomach and wait 30 minutes before eating.
General guidance based on the ingredients, not a substitute for the label or your doctor.
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Sources & Scoring
Nutrient data (RDA, UL, and safety thresholds) sourced from: NIH Office of Dietary Supplements and National Academies Dietary Reference Intakes (DRI).
This is not medical advice. Consult a healthcare provider before making changes to your supplement routine.
The score analyzes what's on the label: ingredient doses vs. clinical ranges, chemical forms, evidence levels, and known interactions. It does not verify label accuracy or test for contaminants — for that, look for third-party certifications like USP or NSF.