Seaweeds have high ash content (20% to 39% by dry weight) and are therefore rich sources of minerals.
Seasonal and geographical variation must be considered when using seaweeds for mineral content. Brown seaweeds tend to be higher in mineral content than red species.
Seaweed mineral content generally consists of macro elements (8-18 gm/100gm) including sodium, potassium, calcium, and magnesium and trace elements (5 to 15 mg/100 gm) including iron, zinc, manganese and copper.
These values tend to be higher than for edible land based plants especially with progressive mineral depletion of food crops. The bioavailability of minerals from seaweed-enriched products is significant. Mineral enriched fractions are being prepared from seaweeds and evaluated as nutraceutical ingredients and functional food additives.