If you've started shopping for an inositol powder, you've probably noticed that every tub and packet looks the same: a white powder, a "40:1" badge, and the word PCOS somewhere on the label. The differences are in the details: how much inositol you get per day, whether it's myo-inositol alone or paired with d-chiro, how you measure it, and what else (if anything) is in there.
So we lined up six popular inositol powders side by side, using only what each brand publishes on its own website. Full transparency: we make one of them (Primal Root). That's exactly why we stuck to label facts and left the hype out.
The quick answer
- Want the highest daily dose of plain inositol, unflavoured? A scoop-style powder like Ovasitol or Wholesome Story gives 2–4g of myo-inositol a day.
- Want myo-inositol only, on a budget? Health & Balance's myo-only powder gives 3g in one scoop.
- Want one pre-measured, flavoured sachet with 40:1 inositol plus active folate and magnesium? That's what we built Primal Root Inositol Powder to be.
What to look for in an inositol powder
1. Myo-inositol alone, or myo + d-chiro at 40:1
Myo-inositol (MI) and d-chiro-inositol (DCI) are the two forms of inositol most studied in PCOS. A 40:1 ratio of myo to d-chiro mirrors the ratio normally found in the blood, and a 2019 trial comparing different ratios found 40:1 performed best of the combinations tested (Nordio et al., 2019). Some brands still sell myo-inositol on its own, which is also well studied.
2. How much you get per day
This is where labels differ most. Most scoop powders are built around 2–4g of myo-inositol a day, split into one or two servings. Always check the daily amount, not just the amount per scoop.
3. How you measure it
A tub with a scoop is usually the cheapest per gram, but you're measuring it yourself every day. Single-serve packets or sachets cost more to make, but every dose is pre-measured and easy to carry.
4. What else is in it
Some inositol powders are 100% inositol. Others add folate, vitamin D, minerals or botanicals so you can take fewer separate products.
5. Taste and testing
Unflavoured powders are the norm. Some people barely notice the taste; others find it slightly sweet or bitter. Look for independent third-party testing, whichever brand you choose.
Inositol powder comparison table
Figures are taken from each brand's website as of September 2026. Always check the current label before buying.
| Product | Format | Per serving | Suggested per day | Also contains | Flavour |
|---|---|---|---|---|---|
| Primal Root Inositol Powder (Regüsk) | Pre-measured 4g sachet | 1,100mg myo + 27.5mg d-chiro (40:1) | 1 sachet | L-methylfolate 440mcg, magnesium glycinate, botanicals (see current label) | Blackberry lemon |
| Ovasitol (Theralogix) | Canister with scoop, or packets | 2,000mg myo + 50mg d-chiro (40:1) | 2 servings (4,000mg + 100mg) | Nothing added | Unflavoured |
| Myo & D-Chiro Inositol Powder (Wholesome Story) | Tub with scoop (2.2g) | 2,000mg myo + 50mg d-chiro (40:1) | 1–2 servings | Nothing added | Unflavoured |
| Inositol Powder (Switch Nutrition) | Tub, 1g scoop | 1,000mg inositol at 40:1 (≈976mg myo + 24mg d-chiro) | 2–4 servings | Nothing added | Unflavoured |
| Myo-Inositol Powder (Health & Balance Vitamins) | Tub with scoop | 3,000mg myo-inositol only | 1 serving | Nothing added | Unflavoured |
| Ovarigen Plus (CalmCo) | Pre-measured 4.37g sachet | Myo + d-chiro at 40:1 (per-ingredient amounts not listed on the brand's website) | 1 sachet | Folic acid, ashwagandha, vitamin D3 | Not stated |
Brand-by-brand notes
Ovasitol
One of the best-known inositol powders, and often recommended by dietitians. It's pure 40:1 inositol with nothing else added, taken as two servings a day for 4g of myo-inositol in total. It's NSF certified and comes as a canister with a scoop or as single-serve packets. It's a strong choice if you want a high daily dose of plain inositol and don't mind taking it twice a day.
Wholesome Story Inositol Powder
Same 2,000mg + 50mg per scoop as Ovasitol, sold in a tub. The brand suggests one to two servings a day. It's unflavoured, and the brand notes the scoop can sometimes get buried in the powder during shipping.
Switch Nutrition Inositol Powder
An Australian 40:1 powder with a smaller 1g scoop, taken two to four times a day. The small scoop makes it easy to adjust your dose, but it also means more scoops to keep track of.
Health & Balance Myo-Inositol Powder
Myo-inositol only: 3g in a single daily scoop, with no d-chiro. It's a simple, affordable option if you or your practitioner prefer myo-inositol on its own.
Ovarigen Plus
The closest format to ours: a single daily sachet with 40:1 inositol plus folic acid, ashwagandha and vitamin D3. The brand's website doesn't list the amount of each ingredient per sachet, so check the physical label if you want to compare doses.
Primal Root Inositol Powder
We built Primal Root for women who want inositol to be one simple step instead of a scoop, a separate folate pill and a magnesium tablet. Each 4g sachet contains 1,100mg myo-inositol and 27.5mg d-chiro-inositol (40:1), L-methylfolate (an active form of folate), magnesium glycinate and a small botanical blend. It comes in a blackberry-lemon flavour that you can take straight, stir into water or add to a smoothie. It's vegan, third-party tested by Eurofins, and comes with a 100-day guarantee.
The honest part: the dose question
You'll notice Primal Root has less myo-inositol per day (1,100mg) than the scoop powders (2,000–4,000mg). That's deliberate, and we'd rather explain it than hide it.
There's no single agreed dose. A 2024 review for the international PCOS guideline covered inositol trials using a range of amounts. Some 40:1 studies used 550mg myo + 13.8mg d-chiro twice a day, the same daily totals as one Primal Root sachet, though in those studies it was given as a soft-gel capsule. The same review found the overall evidence for inositol in PCOS is still "limited and inconclusive," with no clear winner between dosing regimens (Fitz et al., JCEM 2024).
In plain English: if a higher daily dose of plain inositol is your priority, a scoop powder will give you more. If you want a lower, pre-measured 40:1 dose alongside active folate and magnesium in one step, that's where Primal Root fits. Either way, it's worth talking it through with your doctor or dietitian.
Which inositol powder is right for you?
- You want maximum inositol and don't mind scooping: a tub or canister powder (Ovasitol, Wholesome Story, Switch Nutrition).
- You only want myo-inositol: a myo-only powder (Health & Balance).
- You're already taking folate or magnesium separately and want to simplify: a combination sachet (Primal Root, Ovarigen Plus).
- You hate the taste of plain powder or always forget your second scoop: one flavoured, pre-measured sachet a day is easier to stick with.
Try Primal Root Inositol Powder
If one sachet a day sounds more like your kind of routine, take a look at Primal Root Inositol Powder. It's 40:1 myo and d-chiro with active folate and magnesium, and it comes with free shipping and a 100-day guarantee.
Sources
- Fitz V, et al. Inositol for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis to Inform the 2023 Update of the International Evidence-based PCOS Guidelines. J Clin Endocrinol Metab. 2024;109(6):1630–1655. doi:10.1210/clinem/dgad762
- Nordio M, Basciani S, Camajani E. The 40:1 myo-inositol/D-chiro-inositol plasma ratio is able to restore ovulation in PCOS patients: comparison with other ratios. Eur Rev Med Pharmacol Sci. 2019;23(12):5512–5521. PubMed
- Product details: Theralogix (Ovasitol), Wholesome Story, Switch Nutrition, Health & Balance Vitamins, CalmCo (Ovarigen Plus). Accessed September 2026.
This article is for general information only and isn't medical advice. Primal Root is a dietary supplement and is not intended to diagnose, treat, cure or prevent any disease. If you're pregnant, breastfeeding, trying to conceive, taking medication or managing a health condition, talk to your healthcare professional before starting any supplement. Product names belong to their respective owners, and comparison details were accurate to each brand's website at the time of writing.