Lithothamnion superpositum is a species of calcified red marine algae belonging to the Corallinaceae family. It is highly valued commercially as a source of naturally occurring minerals, often used in dietary supplements and food fortification. This calcified algae develops a complex mineral matrix as it grows, offering a concentrated and naturally bound form of mineral content distinct from typical seaweed.
The Biology of a Coralline Algae
Coralline algae are characterized by a rigid, stone-like structure formed by depositing calcium carbonate within their cell walls. L. superpositum develops a nodular thallus, sometimes reaching the size of a kiwi or lemon, and absorbs minerals directly from the surrounding cold seawater into its dense skeletal framework.
The algae’s slow growth rate, sometimes less than one millimeter per year, contributes to the high density of accumulated minerals. When the algae dies, the calcareous fragments detach and accumulate on the seafloor, forming extensive beds of sediment known as maerl. This dead, fossilized maerl material, rather than the living algae, is typically harvested for its mineral content.
Unique Mineral Composition and Bioavailability
The mineral matrix derived from L. superpositum is complex, primarily comprising calcium carbonate and magnesium. Processed algae powder contains approximately 34% calcium and nearly 3% magnesium by weight. The material also includes over 72 different trace elements, such as strontium, boron, zinc, copper, and selenium.
This composition is coupled with a structural advantage that increases effectiveness. The skeletal residue features a highly porous, honeycomb-like structure, often exceeding 40% porosity. This large surface area enhances the solubility and absorption of the minerals in the digestive tract compared to non-algal sources. The presence of the full spectrum of trace minerals also creates a natural synergy, supporting the function and absorption of the primary minerals.
Primary Health Applications
The multi-mineral composition is primarily utilized in products supporting skeletal integrity. Supplementation with Lithothamnion minerals has been studied for reducing bone mineral loss, especially when combined with other bone metabolism nutrients. The blend of calcium, magnesium, and trace elements supports bone density and improves overall bone strength.
The mineral complex is also applied in formulations targeting joint function. Research suggests that Lithothamnion-derived minerals help mitigate discomfort associated with joint conditions like knee osteoarthritis. Furthermore, the harvested material exhibits a naturally alkaline pH (9.5 to 10.5 in a 1% aqueous solution). This alkalinity means the powder can help neutralize excess stomach acid and contribute to maintaining the body’s acid-base balance.
Sourcing and Sustainability Considerations
L. superpositum is found in cold-water regions, including parts of the North Atlantic (Iceland and Ireland) and off the coast of South America. Harvesting methods vary, but the most common practice involves dredging the dead, calcareous maerl sediment from the sea floor. Some operations collect loose material that has naturally accumulated or washed ashore in protected marine areas.
Sustainability is a frequent topic given the algae’s slow growth rate. Since the resource is fossilized, non-renewable sediment, mechanical dredging can be environmentally disruptive, potentially damaging live maerl beds and marine habitats. Certified sustainable harvesting practices, such as selectively collecting only dead, accumulated maerl deposits, are necessary to address environmental concerns. Regulatory bodies often classify harvested maerl as a non-agricultural mineral resource, which affects its eligibility for organic certification.