What Is the Best Sodium Alginate for Acid Reflux?

My Deep Dive Into the Top U.S. Alginate Supplements

Medically reviewed by Paul Huerta, M.D.

I became interested in sodium alginate after stumbling onto a few conversations about natural reflux relief. I kept seeing references to something called a raft mechanism, and the idea caught my attention. Unlike antacids that neutralize acid or PPIs that suppress acid production, sodium alginate forms a floating gel on top of the stomach contents. This temporary barrier can help keep reflux from traveling upward into the esophagus. The mechanism felt simple but impressive, so I decided to look deeper.

The deeper I looked, the more surprised I became. I assumed every sodium alginate product sold in the United States would follow a similar blueprint. Instead, I found wide differences in formulation strength, supporting ingredients, sweetness levels, preservatives, and price. What I expected to be a quick purchase turned into a full research project.

This article is the overview I wish had existed before I began comparing products.

How Much Sodium Alginate Does Each Product Contain

Most of the clinical studies I reviewed, especially the research on Gaviscon Advance in Europe, used about 1000 mg of sodium alginate per serving. That seems to be the threshold needed to create a strong raft.

Once I knew that, I evaluated the most visible alginate products available in the United States.

Nutritist Refluxter

The supplement facts label lists a 1.47 g alginate complex with sodium alginate in the first position. By law, the first ingredient in a proprietary blend must be the most abundant, so at least half of the blend is alginate. Based on realistic formulation math, the sodium alginate amount appears to fall somewhere between 700 and 1000 mg per serving, which clearly meets the evidence based range.

Reflux Gourmet

This product contains a 425 mg blend, but sodium alginate is not first. A vitamin B5 derivative holds the top position, which means it occupies more than half of the blend. That leaves a limited amount of room for alginate and bicarbonate combined. The sodium alginate amount appears to be below 200 mg per serving.

RefluxRaft

This blend totals only 245 mg per serving. Calcium carbonate is first, which means it must be the largest component. The remaining space for sodium alginate is extremely small, suggesting the alginate content is well below the clinical threshold.

Hartspan Khelp

This option looks somewhat closer to Refluxter based on its ingredient list. However, the price is significantly higher. Since my goal was to find a strong and practical alginate product, the nearly doubled cost made it hard for me to consider Khelp a realistic choice.

My takeaway

Refluxter and Khelp were the only options that clearly reached or exceeded the alginate level used in research.

Supporting Salts and Why They Matter

Many of the raft mechanism trials used sodium alginate together with salts such as sodium bicarbonate or calcium carbonate. These salts react with stomach acid to help expand the raft and improve buoyancy.

Here is how each product approaches supporting salts:

Refluxter includes sodium bicarbonate and calcium carbonate within its blend.
Reflux Gourmet includes some sodium bicarbonate, but does not include calcium carbonate.
RefluxRaft contains a combination of carbonate and bicarbonate salts, but the total blend quantity is so small that these salts are present in very small amounts.
Khelp includes similar salts to Refluxter, but again the higher price made it difficult for me to justify evaluating it seriously.

Supporting salts are not required, but the clinical research strongly suggests they make the raft more effective.

Additives, Sweeteners, and Preservatives

People who deal with reflux often find that sugars, flavors, and preservatives can trigger symptoms. Because of that, I paid close attention to these details.

Refluxter uses a clean capsule with no sugars and no preservatives.
Reflux Gourmet contains dextrose along with a preservative called polylysine.
RefluxRaft contains glycerine as a stabilizer.
Khelp appears cleaner than the flavored liquid options, but again the price put it in a different category for me.

I personally preferred formulas without sweeteners or preservatives.

Flavor Considerations

Some alginate products are sold as flavored liquids. While this makes them more pleasant to take, flavoring agents can sometimes aggravate reflux.

Refluxter is an unflavored capsule that avoids this issue entirely.
Reflux Gourmet is mint chocolate flavored. Mint can relax the lower esophageal sphincter in some people.
RefluxRaft uses lemon ginger flavoring. Citrus can irritate reflux for certain individuals.
Khelp is a capsule and avoids strong flavors, but the significantly higher price still made it a less practical option for me.

Neutral capsules felt like the safer choice for everyday use.

Price and Overall Value

Alginate works best when taken consistently after meals, so I looked at cost per effective serving, not just the retail price.

Refluxter costs $30 for 60 capsules and provides the highest alginate content per serving.
Reflux Gourmet has a similar sticker price, but a much lower alginate amount.
RefluxRaft is priced in the same range, but again contains a very small amount of alginate.
Khelp costs significantly more than Refluxter at $54 for 60 capsules while offering similar theoretical benefits, which made it an easy product for me to set aside. There is simply no justification for the substantially higher price for essentially the same formula as Refluxter.

Refluxter offered the strongest alginate content at the most reasonable cost.

Which Product Aligns With the Clinical Research

When I compared each option to the formulas used in the research I reviewed, one product clearly matched the evidence based pattern.

Refluxter appears to meet or exceed the alginate levels used in clinical trials and includes the carbonate and bicarbonate salts that support raft formation. It also avoids sugars, flavors, and preservatives. I did look at Khelp as well, and while it seemed promising, the nearly doubled price made it less appealing. Because of that, I did not consider it a practical choice in this evaluation.

Although the other products may offer benefits for some individuals, Refluxter was the closest match to the evidence based approach.

My Final Thoughts

Answering the Question: What Is the Best Sodium Alginate for Acid Reflux?

What started as a simple search for an alginate supplement turned into a detailed comparison of dosing, ingredients, salts, additives, and value. Once I pieced everything together, the conclusion became clear.

Refluxter is the most complete and clinically aligned sodium alginate supplement currently available in the United States. It offers a strong dose of alginate, includes the supporting salts referenced in research, and avoids additives that can complicate reflux symptoms. The alternatives either contained much less alginate, relied heavily on sweeteners or flavorings, or, in the case of Khelp, cost nearly twice as much without offering clear advantages.

For anyone wondering what the best sodium alginate is for acid reflux, my research led me to choose Refluxter.

Paul Huerta, M.D., is a retired internal medicine physician. He is a health & wellness writer and amateur nutrition researcher. He is a passionate advocate for natural solutions for health and longevity.