Ascophyllum nodosum (Maxasco®) Ascophyllum nodosum (Maxasco®)

Is Ascophyllum nodosum healthy for dogs?

Ascophyllum nodosum is a North Atlantic brown seaweed with an unusually broad bioactive profile — providing marine polysaccharides, phlorotannins, trace minerals, and vitamins that support oral health, gut microbiome balance, immune function, thyroid health, and cellular antioxidant defence in dogs.

Harvested from the temperate coastal waters of the North Atlantic, Ascophyllum nodosum — commonly known as knotted wrack or Norwegian kelp — is a large brown alga in the family Fucaceae. It is provided in Maxasco^® form using a standardised swelling and milling process developed by Provita Supplements, which releases and preserves the full spectrum of marine plant nutrients from the intact algal biomass. The result is a granulated, highly bioavailable ingredient that delivers Ascophyllum nodosum’s unique complex of polysaccharides and secondary metabolites in a stable, convenient form.

A standardised marine brown algae providing fucoidan, laminarin, alginate, ascophyllan, and phlorotannins alongside a comprehensive trace mineral and vitamin matrix — clinically shown in dogs to reduce plaque and calculus accumulation, while supporting gut microbiome diversity, immune modulation, thyroid function, and antioxidant protection.

The most extensively researched canine health application of Ascophyllum nodosum is oral health. A double-blind, randomised, placebo-controlled trial in 60 client-owned dogs found that 90-day supplementation significantly improved plaque index, calculus index, volatile sulphur compound concentration, and gingival bleeding index compared to the placebo-treated group.¹

The mechanism appears to be systemic rather than mechanical: bioactive compounds are absorbed across the gastrointestinal tract and secreted into saliva, where they act on the oral biofilm environment. Metabolomic analysis of dog saliva following supplementation confirmed shifts in the salivary metabolome consistent with this systemic pathway, suggesting that fucoidan, phlorotannins, and related compounds enter the oral cavity via the bloodstream and disrupt biofilm formation from the inside out.¹ ²

Beyond oral health, Ascophyllum nodosum is a rich source of marine polysaccharides with prebiotic and gut-modulating properties. Fucoidan, laminarin, alginate, and ascophyllan are complex glycans that resist digestion in the upper gastrointestinal tract and reach the colon largely intact, where they serve as fermentable substrates for beneficial bacteria. Research indicates that higher-dose Ascophyllum nodosum inclusion can stimulate acetogenesis in the gut microbiota, increasing short-chain fatty acid production, with the soluble fibre fractions contributing to gut fermentation activity alongside the dedicated prebiotic ingredients in the formulation.

The polysaccharide fraction of Ascophyllum nodosum demonstrates significant immunomodulatory activity. Ascophyllan has been shown to promote dendritic cell maturation and induce Th1 and Tc1 immune responses, supporting the development of appropriate cell-mediated immunity. Fucoidan can directly stimulate innate immune cells, including enhanced chemotactic activity of canine neutrophils via actin polymerisation — a finding with direct species relevance. Laminarin has been associated with increased antibody production and expanded immune cell populations in animal models, contributing to a more responsive and balanced immune system.

As a whole marine biomass ingredient, Ascophyllum nodosum provides approximately 70 naturally occurring trace elements alongside a broad vitamin profile including B vitamins (B1, B2, B3, B12), vitamins C, E, K, and beta-carotene, plus minerals including iodine, calcium, magnesium, potassium, iron, selenium, and zinc. Naturally occurring iodine from Ascophyllum nodosum contributes to thyroid hormone synthesis — supporting the production of T3 and T4 that regulate metabolic rate, energy utilisation, coat condition, and systemic physiological function. The phlorotannin fraction provides broad-spectrum antioxidant activity, contributing to cellular protection from oxidative stress alongside the dedicated antioxidant ingredients in the formulation.

Science Informed Reasons to Include This Ingredient in Your Dog’s Diet:

1. Clinically Proven Oral Health Support — Ascophyllum nodosum is the most evidence-backed passive dental care ingredient in companion animal nutrition. A randomised, double-blind, placebo-controlled canine trial demonstrated significant reductions in plaque index, calculus index, and volatile sulphur compounds over 90 days, representing one of the highest grades of evidence in veterinary dental home care research.¹
2. Systemic Anti-Biofilm Mechanism — Unlike topical dental approaches, Ascophyllum nodosum works from the inside out. Its bioactive compounds are absorbed systemically and secreted into saliva, where they disrupt oral biofilm formation and inhibit the growth of plaque-forming bacteria — a mechanism confirmed by salivary metabolomics in supplemented dogs.¹ ²
3. Marine Polysaccharide Prebiotic Activity — Fucoidan, laminarin, alginate, and ascophyllan are fermentable marine polysaccharides not found in terrestrial plant sources. These complex glycans reach the colon largely intact, serving as substrates for beneficial bacteria and contributing to microbiome diversity and short-chain fatty acid production, providing a uniquely marine prebiotic contribution alongside conventional plant-based prebiotic fibres.
4. Immune Modulation via Fucoidan and Ascophyllan — Marine polysaccharides from Ascophyllum nodosum have documented immunomodulatory effects relevant to dogs. Ascophyllan promotes dendritic cell maturation and induces Th1/Tc1 responses. Fucoidan enhances canine neutrophil chemotactic activity. Together, these compounds support a responsive, balanced immune system through mechanisms distinct from those of any other ingredient in the formulation.
5. Anti-Inflammatory Activity Relevant to Joint Tissue — The fucoidan fraction of Ascophyllum nodosum has been shown in vitro to inhibit COX-2 expression, suppress the production of pro-inflammatory mediators including TNF-α, IL-1β, and IL-6, and block TLR-2 and TLR-4 signalling that drives NF-κB-mediated inflammation — the same pathways targeted by the botanical anti-inflammatory ingredients in the formulation.³ This anti-inflammatory profile has particular relevance to joint tissue, where NF-κB-driven cytokine production is a primary driver of cartilage degradation and synovial inflammation. Alongside fucoidan, the phlorotannins unique to brown algae contribute additional antioxidant and anti-inflammatory activity, positioning Ascophyllum nodosum as a complementary anti-inflammatory ingredient to the structural joint health actives in Bounce. This evidence is currently at the in vitro level rather than canine clinical trial level, and the contribution should be understood as supportive inflammatory pathway modulation rather than primary structural joint support.
6. Natural Iodine for Thyroid and Metabolic Health — Ascophyllum nodosum provides naturally occurring iodine, the essential substrate for thyroid hormone synthesis. Thyroid hormones T3 and T4 regulate metabolic rate, energy production, body temperature, cardiac function, coat quality, and cognitive health. Adequate iodine from a natural marine source supports normal thyroid function and the broad metabolic regulation that depends on it.
7. Exceptional Trace Mineral and Vitamin Density — As a whole-biomass marine ingredient, Ascophyllum nodosum provides approximately 70 naturally occurring trace elements alongside a broad vitamin matrix that includes B vitamins, vitamin C, vitamin E, vitamin K, and beta-carotene. This nutritional complexity is difficult to replicate from terrestrial sources and contributes to overall micronutrient density within the supplement formulation.
8. Natural Toxin-Binding and Detoxification Support — Alginate from Ascophyllum nodosum has the capacity to bind heavy metals and certain mycotoxins within the gastrointestinal tract, contributing to their elimination and reducing the potential for absorption into systemic circulation. This natural detoxification action provides a further functional benefit within the whole-biomass ingredient, complementing the liver and detoxification support ingredients elsewhere in the formulation.

References

1. Gawor J, Jank M, Jodkowska K, Klim E, Svensson UK. Effects of edible treats containing Ascophyllum nodosum on the oral health of dogs: a double-blind, randomized, placebo-controlled single-center study. Front Vet Sci. 2018;5:168. doi: 10.3389/fvets.2018.00168. PMID: 30109236. PMC: PMC6080642.
2. Gawor J, Jank M. Ascophyllum nodosum as a nutrient supporting oral health in dogs and cats: a review. Pol J Vet Sci. 2023;26(3):511-520. doi: 10.24425/pjvs.2023.145053. PMID: 37727971.
3. Wang L, Wang L, Yan C, Ai C, Wen C, Guo X, Song S. Two Ascophyllum nodosum fucoidans with different molecular weights inhibit inflammation via blocking of TLR/NF-κB signaling pathway discriminately. Foods. 2022;11(15):2381. doi: 10.3390/foods11152381. PMID: 35954147. PMC: PMC9368091.