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Proprietary Blend Math: A Three-Step Way to Find the Most Each Name Can Hold
To calculate proprietary blend amounts, you divide the blend total by the place of each name on the list. Rules in 21 CFR 101.36 list blend names from most to least by weight. On the Reviralis label, 661 mg shared by 18 names means the fifth name, bacopa, can hold at most 132.2 mg. These are ceilings, not doses.
Written by the Reviralis label deskUpdated · 4 min read
The rule01
What rule makes blend math possible?
The rule is that blend names must be listed from the most weight to the least. That order is what lets a reader put a ceiling on a name even when no amount is printed.
A company may print one total for a blend and skip the single amounts. The names still go in descending order by weight, and the total is the weight of all of them together (21 CFR 101.36, Supplement Facts Panel). The Reviralis label gives 661 mg per serving and 18 names. The total, the count and the order are your only tools.
Three steps02
How do you calculate the most a blend name can hold?
Divide the blend total by the name's place on the list, and round up to one decimal. The answer is the most that name can weigh.
Write down the total and the count
661 mg and 18 names.
Number the names from the top
DMAE bitartrate is 1, L-glutamine 2, and so on to phosphatidylserine at 18.
Divide 661 by the place number
Name number 5 is bacopa. 661 divided by 5 is 132.2 mg.
Why does it work? If the fifth name weighed more than 132.2 mg, the four above it would weigh at least as much, and the five together would pass 661 mg.
Worked numbers03
What are the ceilings for the Reviralis blend?
The first name has a floor and every other name has a ceiling. DMAE bitartrate must be at least 36.7 mg, and the last name, phosphatidylserine, can hold at most 36.8 mg.
| Place | Name | Sum | At most |
|---|---|---|---|
| 2 | L-glutamine | 661 / 2 | 330.5 |
| 5 | Bacopa monnieri extract | 661 / 5 | 132.2 |
| 9 | GABA | 661 / 9 | 73.5 |
| 12 | Olive leaf powder | 661 / 12 | 55.1 |
| 16 | DHA | 661 / 16 | 41.4 |
| 18 | Phosphatidylserine (sunflower seed) | 661 / 18 | 36.8 |
All 18 rows are on the proprietary blend page.
Reviralis: from $49 a bottle60 capsules a bottle · 2, 3 or 6 bottles · free US shipping on 3 and 6 · 60-day money-back guarantee
See packsWhat it cannot tell you04
What can blend math not tell you?
It cannot tell you the real amount. A ceiling is the most a name could hold if every name above it were as small as the rules allow.
The ceilings also cannot all be true at once. They add up to far more than 661 mg.
Use the numbers to compare against studies, never to say a name is "enough" or "too little". Bacopa at 132.2 mg or less of extract is below the 300 mg a day used in one trial (Calabrese 2008, Bacopa in Older Adults (J Altern Complement Med)), but the label does not say how strong the extract is.
The weight-order rule itself is covered in ingredients listed in descending order.
661 mgone proprietary blend per serving (2 capsules), shared by 18 names; the 22 vitamin and mineral lines print their own amounts
Proprietary Blend 661 mg · 18 names · no single amounts- 1. DMAE bitartrate36.7 to 661 mg
- 2. L-glutamineup to 330.5 mg
- 3. Glutamic acidup to 220.4 mg
- 4. Green tea leaf extractup to 165.3 mg
- 5. Bacopa monnieri extractup to 132.2 mg
- 6. Inositolup to 110.2 mg
- 7. N-acetyl L-tyrosineup to 94.5 mg
- 8. Bilberry fruit extractup to 82.7 mg
- 9. GABAup to 73.5 mg
- 10. Grape seed extractup to 66.1 mg
- 11. Grapefruit seed extractup to 60.1 mg
- 12. Olive leaf powderup to 55.1 mg
- 13. Cinnamon bark extractup to 50.9 mg
- 14. Licorice root extractup to 47.3 mg
- 15. Boron (citrate)up to 44.1 mg
- 16. DHAup to 41.4 mg
- 17. Vanadyl sulfateup to 38.9 mg
- 18. Phosphatidylserineup to 36.8 mg
Bars are drawn on a 0 to 661 mg scale. Each bar shows the widest range the label order allows for that name (21 CFR 101.36, Supplement Facts Panel); the real split is not printed. The first name is at least 36.7 mg; the n-th is at most 661 divided by n.
Your turn05
Can you run the math on any supplement label?
Yes, if the label shows a blend total and a name list. The method is the same for any blend with a single weight.
Try a made-up blend of 500 mg with 5 names. The third can hold at most 166.7 mg, the fifth at most 100 mg, and the first is at least 100 mg. With no total printed there is nothing to divide, so ask the seller; the Supplement Facts page shows what a full panel prints.
FAQ06
Reviralis questions people ask
Why do you round the ceiling up?
Rounding up to one decimal keeps the ceiling safe to state. 661 divided by 3 is 220.33, shown as 220.4.
Is the first name in a blend always the biggest?
Yes, the first name is the heaviest or tied for heaviest, because names go in descending order by weight (21 CFR 101.36, Supplement Facts Panel). On the Reviralis label that is DMAE bitartrate, which is at least 36.7 mg but could be far more, up to the full 661 mg.
Do the ceilings change with each capsule?
No. The label amounts are per serving of 2 capsules. The label says to take two capsules, so the site uses per-serving figures.
Does this math work for the vitamin and mineral lines?
No. Those 22 lines print their own amounts, so there is nothing to work out. Blend math is only for names inside a proprietary blend, where one total covers many names.
Who wrote this07
Written and reviewed by
Pages built from the label, the order page and linked NIH, FDA, FTC, Mayo Clinic and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is the information site for a USA Authorized Reviralis Retailer. It is not the manufacturer or the distributor named on the label. We earn money when you buy through our order links.
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