Last updated on September 21st, 2026 at 09:52 am
Most sea moss nutrition articles describe everything as “rich in” or “packed with” minerals without ever stating an actual number. Here’s what raw Chondrus crispus actually contains per serving, sourced from USDA data rather than marketing language.
This guide breaks down what’s actually inside sea moss, using USDA reference data for raw Chondrus crispus, the most extensively tested species.
Nutrient levels can vary by type, source, and preparation, so figures here are a reference point rather than an exact match for every product.
For the broader picture of what these nutrients can and can’t do for your health, see our sea moss benefits guide. For the species distinctions that affect these numbers, see our sea moss guide.
Disclaimer: Six Herbs is an educational resource, not a medical service. Nothing in this article constitutes medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before using any herb or supplement, particularly if you are pregnant, breastfeeding, taking medication, or managing a health condition.
Table of Contents
Macronutrients
Raw Chondrus crispus is low in calories and fat, with most of its structure coming from carbohydrates and fiber rather than protein.
| Nutrient | Per 100g (raw) | Per typical 10g serving |
|---|---|---|
| Calories | About 49 kcal | About 5 kcal |
| Carbohydrates | About 12 g | About 1.2 g |
| Dietary fiber | About 1 g | About 0.1 g |
| Protein | About 1.5–2 g | About 0.15–0.2 g |
| Fat | About 0.2 g | Negligible |
The carbohydrate content is mostly structural, made up of polysaccharides like carrageenan rather than sugars. This is what gives soaked, blended sea moss its gel-like texture.
Protein content is minor; sea moss isn’t a meaningful protein source compared to something like spirulina, which contains roughly 65 grams of protein per 100 grams.
Minerals
Sea moss provides a documented, if modest, range of minerals per serving, detailed in this nutritional analysis of Chondrus crispus and related seaweeds.
| Mineral | Per 100g (raw) | Role |
|---|---|---|
| Calcium | About 70 mg | Bone and teeth structure |
| Iron | About 9 mg | Oxygen transport, hemoglobin formation |
| Potassium | About 60 mg | Fluid balance, nerve signaling |
| Magnesium | About 140 mg | Muscle function, energy reactions |
| Phosphorus | About 160 mg | Bone structure, energy storage |
| Sodium | About 70 mg | Electrolyte balance |
A note on iodine. Sea moss is a documented source of iodine, but its content varies widely between products and species, detailed in this study on iodine variability in seaweed products. This variability is also the reason iodine is sea moss’s biggest safety consideration; see the side effects and safety guide for the fuller picture.
Vitamins
Vitamin content is present but modest per serving, with folate standing out as the most notable contributor.
| Vitamin | Per 100g (raw) |
|---|---|
| Folate (B9) | About 180 mcg |
| Vitamin C | About 3 mg |
| Vitamin A | About 10 mcg |
| Vitamin B2, B3, E, K | Present in smaller, less consistently measured amounts |
The folate figure is worth noting directly, since it covers a meaningful share of daily recommended intake in a small serving.
Vitamin C and A contributions are smaller, more comparable to a modest side dish than a citrus fruit.
Bioactive Compounds
Carrageenan, a sulfated polysaccharide, is the main structural compound in sea moss and the reason it forms a gel when soaked and blended.
It isn’t a nutrient in the traditional sense, since the body doesn’t absorb it for energy. It does have documented prebiotic potential, covered in more depth in our sea moss benefits guide.
Sea moss also contains measurable antioxidant compounds, detailed in the same nutritional analysis cited above.
How Type and Processing Affect Nutrition
Nutrient content shifts meaningfully depending on species and preparation, not just marginally.
- Species matters more than color. Gold and purple varieties commonly come from different genera entirely, not just different pigmentation of the same plant. See our sea moss guide for the full explanation of why this affects mineral content.
- Drying concentrates nutrients per gram, but not per serving. Removing water increases nutrient density by weight, but a typical serving of gel already accounts for its water content, so the practical difference is smaller than it sounds.
- Wildcrafted versus farmed can affect mineral diversity. Wild-harvested sea moss absorbs minerals directly from its ocean environment, which can mean more variation between batches. Farmed sea moss tends to be more consistent but not necessarily more or less nutritious overall.
Sea Moss Compared to Other Sea Vegetables
Sea moss is lower in calories than many dried seaweeds and sits in a similar mineral range to other red algae.
Its carrageenan content and gel-forming property set it apart from kelp or nori.
It’s meaningfully lower in protein than spirulina or chlorella, so it’s best understood as a mineral-dense addition to a diet rather than a protein source.
Conclusion
Sea moss offers a solidly useful nutrient profile: modest calories, structural fiber from polysaccharides, and meaningful calcium, iron, magnesium, and phosphorus content.
It also provides a notable folate contribution, all backed by actual per-serving figures rather than vague claims.
Its biggest nutritional variable is iodine, which differs enough between products to deserve its own attention rather than a passing mention.
These numbers apply most directly to Chondrus crispus specifically; other commercially sold varieties can differ in mineral density.
For what these nutrients can plausibly do for your health, see our sea moss benefits guide.
Frequently Asked Questions
How many calories are in sea moss?
Raw Chondrus crispus contains about 49 calories per 100 grams, or roughly 5 calories in a typical 10-gram serving, making it a low-calorie addition to most diets.
What are the main minerals in sea moss?
Calcium, iron, potassium, magnesium, phosphorus, and sodium are the most consistently measured minerals, with iron and magnesium standing out as particularly notable per serving.
Does sea moss contain a meaningful amount of protein?
No, sea moss contains only about 1.5 to 2 grams of protein per 100 grams, making it a mineral source rather than a protein source in your diet.
Do different types of sea moss have different nutrition?
Yes, species matters more than color; Gracilaria and Chondrus crispus have different mineral profiles, and processing method affects nutrient concentration by weight.
Chims Clements writes about herbs from personal experience and careful research. Growing up in Aba, Nigeria, moringa and tamarind were everyday household plants long before they became globally recognised superfoods. He uses both regularly in his home today. At Six Herbs he goes deep on moringa, tamarind, fenugreek, and sea moss — building honest, experience-backed content that separates what tradition knows from what science confirms. The content on this site is for informational purposes only and is not medical advice. Always consult a healthcare provider before using herbs medicinally.