On the labels we read on November 3, 2026, cost per serving runs from about $0.75 (200-count sea moss and bladderwrack) to $1.20 (140-count sea moss). Among the three labels that state iodine, it runs from 6 to 561 micrograms per serving, against NIH's adult recommended intake of 150 and upper limit of 1,100. The cheapest serving also prints the most iodine, so compare iodine before price.
Sea moss capsules are the one sea moss format where the label does the comparing for you: a serving size, an amount per serving and, often, an iodine figure. So we compared the five capsule labels from Alkaline Herb Shop, our affiliate retailer, on cost per serving, what is in a serving and the iodine each label prints. "Best" here means best by a stated criterion, not an endorsement. We have not tested any of these products.
Cost per serving
Prices and label details below are what the retailer's pages showed on November 3, 2026. Prices change, and two of the products are on sale.
| Capsule | Price and serving | Cost |
|---|---|---|
| Sea Moss & Bladderwrack, 200 count | $49.99. A serving is 3 capsules, and the bottle holds about 67. | $0.75 per serving. $0.42 per gram of contents. |
| Sea Moss & Bladderwrack, 90 count | $29.99. A serving is 3 capsules, and the bottle holds 30. | $1.00 per serving. $0.56 per gram of contents. |
| Sea Moss, 140 count | $41.99. A serving is 4 capsules, and the bottle holds 35. | $1.20 per serving. $0.50 per gram of contents. |
| Sea Moss & Elderberry, 90 count | $29.99 on sale (regular $39.99). A serving is 3 capsules, and the bottle holds 30. | $1.00 per serving on sale, $1.33 at the regular price. $0.74 per gram on sale, $0.99 regular. |
| Sea Moss & Moringa, 90 count | $29.99 on sale (regular $39.99). A serving is 3 capsules, and the bottle holds 30. | $1.00 per serving on sale, $1.33 at the regular price. $0.74 per gram on sale, $0.99 regular. |
Cost per serving is the price divided by servings per bottle. Cost per gram of contents divides the price by the plant material in the whole bottle, using the milligrams per capsule the labels and listings give: 600 mg for the sea moss and bladderwrack and the sea moss only products, and 450 mg for the elderberry and moringa blends. The second number matters because a "serving" is a different size in each product. It still compares plant material, not value, because the ingredients differ. The retailer's own FAQ says the 200-count works out to roughly 63 cents a serving against a dollar for the 90-count. At the $49.99 price we saw, we calculate about 75 cents.
What is in a serving, and the iodine each label prints
| Capsule | In one serving | Iodine printed per serving |
|---|---|---|
| Sea Moss & Bladderwrack, 200 count | 900 mg sea moss and 900 mg bladderwrack | 561 mcg (374% of the label's daily value) |
| Sea Moss & Bladderwrack, 90 count | 900 mg sea moss and 900 mg bladderwrack, per the retailer's FAQ | Not found in the listing text we read |
| Sea Moss, 140 count | 2,400 mg sea moss. The label also lists 4 mg iron, 120 mg calcium, 30 mg magnesium and 0.3 mg zinc. | 364 mcg (243% of the label's daily value) |
| Sea Moss & Elderberry, 90 count | 675 mg sea moss and 675 mg elderberry fruit | 6 mcg, per the retailer's FAQ |
| Sea Moss & Moringa, 90 count | 675 mg sea moss and 675 mg moringa leaf, per the retailer's FAQ | Not found in the listing text we read |
"Not found" means the figure was not in the page text we could read. A Supplement Facts panel shown only as an image would not appear there, so check the product page.
Two of the pages link a lab report: the 200-count for lot 240157, dated May 26, 2026, and the 140-count for lot 250636, dated November 6, 2025. We found no report link in the text of the other three pages. The reports are lot-specific. We have not reviewed them, and the retailer's testing statements are shown as claims, not as results we verified.
Reading the iodine numbers
NIH's Office of Dietary Supplements sets the adult recommended intake for iodine at 150 micrograms a day and the upper limit at 1,100 micrograms a day from all sources. It says people with autoimmune thyroid disease may have adverse effects at intakes considered safe for the general population. On that scale, the 200-count's printed 561 micrograms is about half the upper limit in one serving, and the 140-count's 364 micrograms is about a third. Both are before any iodine from food, iodized salt or other supplements.
Something else stands out when you divide the printed iodine by the seaweed in the serving:
- The 140-count prints 364 micrograms for 2,400 mg of sea moss, about 152 micrograms per gram.
- The 200-count prints 561 micrograms for 1,800 mg of sea moss and bladderwrack together, about 312 micrograms per gram.
- The elderberry blend prints 6 micrograms for 675 mg of sea moss, under 10 micrograms per gram.
For comparison, NIH says iodine in commercially available whole or sheet seaweeds ranges from 16 to 2,984 micrograms per gram. The labels do not say why the figures differ so much, and we cannot tell whether it reflects the lot, how the figure was derived or something else. The practical lesson is that a blend with less sea moss does not necessarily carry proportionally less iodine, and that a lot-matched lab report is the only way to know. Read the iodine on the label before you read the price. Our guide to how much iodine is too much explains the reference values.
Best by one criterion
- Lowest cost per serving on these labels: the 200-count sea moss and bladderwrack, at about $0.75. It also prints the most iodine per serving.
- Single-ingredient label: the 140-count sea moss only. It costs more per serving at $1.20 and prints 364 micrograms of iodine.
- Lowest printed iodine per serving: the elderberry blend, at 6 micrograms, at $1.00 a serving while the sale lasts.
- Smallest commitment: any of the 90-count bottles, each 30 servings.
- If you also use another seaweed product: count the iodine from every source together. Gel, powder, bladderwrack and capsules all add up.
None of these is a recommendation. The right product depends on your thyroid health, medicines, pregnancy status and diet, which a clinician can weigh and we cannot.
The five capsules we list
These are our listings from Alkaline Herb Shop. Lab results are shown only as the retailer states them, and prices on the cards may be older than the ones in the tables above. Confirm the price, serving size and iodine on the retailer's page before you order.
Sea Moss & Bladderwrack Supplement 200 Capsules
Capsules that pair Irish sea moss with bladderwrack, 900 mg of each in the three-capsule serving the retailer lists. High in iodine by the retailer's own numbers.
- Format: Capsules
- Size: 200 vegetable capsules
- Category: Sea Moss
- Price: $49.99 (checked November 3, 2026)
- Lab evidence: Merchant states third-party testing. CannaWize has not reviewed the results.
Sea Moss & Bladderwrack 90 Capsules
A smaller 90-capsule bottle that combines sea moss and bladderwrack. Check the label for the amount of each seaweed and the iodine per serving before comparing it with the 200-count size.
- Format: Capsules
- Size: 90 capsules
- Category: Sea Moss
- Price: $29.99 (checked November 3, 2026)
- Lab evidence: Lab results not reviewed by CannaWize
Sea Moss Supplement 140 Capsules
Single-ingredient sea moss capsules, 140 per bottle. A simpler label than the combination products, which can make serving comparisons easier.
- Format: Capsules
- Size: 140 capsules
- Category: Sea Moss
- Price: $41.99 (checked November 3, 2026)
- Lab evidence: Lab results not reviewed by CannaWize
Sea Moss & Elderberry Supplement 90 Capsules
Sea moss paired with elderberry in a 90-capsule bottle. Combination products make it harder to see how much of each ingredient you get, so read the supplement facts panel.
- Format: Capsules
- Size: 90 capsules
- Category: Sea Moss
- Price: $29.99 (checked November 3, 2026)
- Lab evidence: Lab results not reviewed by CannaWize
Sea Moss & Moringa Supplement 90 Capsules
Sea moss and moringa together in a 90-capsule bottle. Look for the amount of each ingredient per serving on the supplement facts panel.
- Format: Capsules
- Size: 90 capsules
- Category: Sea Moss
- Price: $29.99 (checked November 3, 2026)
- Lab evidence: Lab results not reviewed by CannaWize
Affiliate disclosure: CannaWize may earn a commission if you buy through links on this page, at no extra cost to you. CannaWize does not sell these products. You complete your purchase on the retailer's website, and the retailer handles pricing, shipping and returns.
A short buying checklist
- Botanical names for every ingredient, including Chondrus crispus for the sea moss.
- Milligrams of each ingredient per serving, not just a total.
- Iodine per serving, compared with 150 micrograms recommended and 1,100 micrograms as the upper limit.
- A lab report that matches the lot on your bottle. See how to read a sea moss lab report.
- The sale price and the regular price, if a listing shows both.
- A clinician's view if you have a thyroid condition, are pregnant or breastfeeding, or take medicine. See sea moss side effects and who should avoid it.
If you are weighing capsules against making gel or buying powder, our format comparison and gel guide cover the trade-offs.
Frequently asked questions
Which sea moss capsules are cheapest per serving?
Of the five labels we compared on November 3, 2026, the 200-count sea moss and bladderwrack worked out to about $0.75 a serving, against $1.00 for the 90-count products and $1.20 for the 140-count sea moss. It also printed the most iodine, 561 micrograms a serving. Sources: retailer 200-count listing and 140-count listing.
How much iodine is in sea moss capsules?
On the labels that state it, 561 micrograms per serving for the 200-count sea moss and bladderwrack, 364 micrograms for the 140-count sea moss and 6 micrograms for the sea moss and elderberry blend, per the retailer's FAQ. NIH's adult recommended intake is 150 micrograms and its upper limit is 1,100. Sources: NIH ODS and the retailer listings.
Are these sea moss capsules third-party tested?
The retailer says its capsules are third-party tested for heavy metals, identity and microbials, and the 200-count and 140-count pages link lab reports for specific lots. We have not reviewed the reports, so we show testing as the retailer's claim. Source: retailer listing.
Does a sea moss and bladderwrack capsule have more iodine than sea moss alone?
On the labels we read, yes: 561 micrograms per serving for the 200-count sea moss and bladderwrack against 364 for the 140-count sea moss. NIH notes that iodine varies greatly between seaweed species, so read the label for each product. Sources: NIH ODS and the retailer listings.
Sources and further reading
- Retailer product page: Sea Moss & Bladderwrack 200 capsules (Alkaline Herb Shop)
- Retailer product page: Sea Moss & Bladderwrack 90 capsules (Alkaline Herb Shop)
- Retailer product page: Sea Moss 140 capsules (Alkaline Herb Shop)
- Retailer product page: Sea Moss & Elderberry 90 capsules (Alkaline Herb Shop)
- Retailer product page: Sea Moss & Moringa 90 capsules (Alkaline Herb Shop)
- NIH Office of Dietary Supplements: Iodine, health professional fact sheet