Life Extension Magazine®

Woman suffering from acid reflux using natural raft-forming alginate for relief

Block Acid Reflux to Prevent Esophageal Problems

A variety of drugs reduce stomach acid, but none prevent the backwash of stomach contents into the esophagus that exacerbates heartburn and increases esophageal cancer risk. A natural, raft-forming alginate can provide esophageal relief by blocking reflux of stomach contents into the esophagus…without drugs!

Scientifically reviewed by: Andrew Roberts Jr., MPH in Global Health, MS in Medical Health, in May 2022. Written by: Kirk Stokel.

Block Acid Reflux to Prevent Esophageal Problems!

Gastro esophageal reflux disease or GERD affects 60 million Americans.

Most GERD suffers seek ways to relieve pain and burning, such as taking proton-pump inhibiting drugs like Prilosec® or Prevacid®.1

These drugs suppress stomach acid formation, but do not block the backwash of harsh stomach contents (such as digestive enzymes, bile, and acidic foods) into the delicate esophageal lining. A consequence of chronic esophageal exposure to stomach contents is deadly esophageal cancer!2,3

The link between esophageal reflux and esophageal cancer is striking. People who have long-standing and severe GERD symptoms have 43 times the risk of getting esophageal cancer, which is likely to kill over 15,000 Americans this year.2,3

Prevalence of adenocarcinoma of the esophagus has been skyrocketing in comparison with which used to be more common squamous cell carcinoma.4,5 Researchers speculate the obesity epidemic is causing more cases of adenocarcinoma of the esophagus, whereas squamous cell carcinoma is largely attributed to cigarette smoking and excess ethanol ingestion.5-7

A new approach has been discovered to impede backwash of all stomach contents (including acid) into the esophagus. By chewing on tablets composed of marine alginate and bicarbonate—known as a raft-forming alginate, one can physically block the backwash of burning acid and other stomach contents into the delicate tissue of the esophagus.8 This provides a relatively pH-neutral barrier to relieve painful heartburn—and potentially reduce the risk of esophageal cancer!8

In this article, you’ll learn how this unique mechanism has been shown to work, often within a few seconds of dosing, to form a barrier that can be retained in the stomach for hours, providing longer-lasting relief than the mechanism of traditional antacids.8

Raft-Forming Alginate Physically Blocks Reflux!

Raft-forming alginates protect the delicate esophagus via a unique mechanism.8

They produce a temporary physical barrier that blocks stomach contents from backing up into the esophagus.8

As the alginate mixture expands in the stomach, it mops up excess acid and forms a pH-neutral barrier that reduces reflux episodes.

Here’s how an alginate-based raft-forming formulation works…

One component of the mixture—alginic acid—is a dry powder containing natural long-chain carbohydrate molecules derived from brown seaweed. On contact with liquid and acid in the stomach, it forms a thick gel.8

When another component of the mixture—potassium bicarbonate—comes in contact with gastric acids, it produces carbon dioxide bubbles that get trapped in the gel.8 The expanding bubbles cause the thick gel to form a floating foam that literally sits atop the stomach contents like a raft.8

Two additional ingredients, calcium carbonate and magnesium carbonate, react with the soft foam, adding loft and tightening it up into a firmer (but temporary) “raft.”8

Studies show that in people with acid reflux the raft slides up into the lower esophagus and creates a barrier, which prevents acid in the stomach from pushing up into the esophagus.8,9

Of course, carbonate and bicarbonate in the mixture react with stomach acid as they form carbon dioxide, helping to neutralize stomach acidity and providing a second important mechanism for relieving heartburn.8

The combined effect of all this action has been shown to reduce the severity of symptoms and the frequency of reflux episodes.8 Reflux sufferers will recognize that as a huge improvement over standard antacids.

The entire raft-forming process takes less than a minute, though the raft can survive in the stomach for as long as four hours until it is broken up and passed out of the body.8 This explains the remarkably rapid and long-duration relief you can get from using a raft-forming alginate immediately following a meal.8

Raft-Forming Alginates Reduce Both Acids—and Reflux!

Raft-Forming Alginates Reduce Both Acids—and Reflux!  

For suffers of reflux and heartburn, doctors are interested in strategies that both cut the acid content of the stomach and block acid and food reflux.10

Traditional antacids can only reduce acids—but raft-forming alginates can do both!

Compelling studies show that alginate preparations are highly effective at reducing both the intensity and the frequency of reflux attacks.8,11

In one study, using sophisticated pressure and acid-monitoring equipment, 20 mL of alginate kept the esophagus in the non-acidic range nearly 3 times longer than placebo and cut the incidence of food reflux by half.10

Another study, of a single dose of a liquid form of an alginate-based formula showed a soothing effect in an average of just 65-66 seconds! Over 82% of subjects described the effects as “instant” relief.12 In this study, a full 100% of patients experienced heartburn relief within just 3.3 minutes after the dose.

Unlike prescription antacid medications such as Prilosec® (omeprazole), alginate formulations can have beneficial impact on reflux damage to the larynx, or voice box. Significant differences in objective scores based on the appearance and condition of the larynx were seen between subjects taking 10 mL of alginate suspension four times daily (after meals and at bedtime), compared to placebo subjects.13

Even more impressive than these placebo-controlled studies is research that compared alginates with other antacids.

One such study found significantly greater improvement in heartburn symptoms in patients treated four times daily with 200 mg of cimetidine (Tagamet®) plus 500 mg of alginate than in patients treated four times daily with 400 mg of cimetidine alone, and the rates of healing and improved appearance of damaged esophagus were similar between the two groups.14

A related study found that a single 20 mL dose of an alginate formulation alone was better than an alginate-cimetidine combination at reducing both food and acid reflux.15

Other studies have shown marked reduction in symptom severity scores with alginates compared to Propulsid® (cisapride), a reflux medication,16 and with Prilosec® (omeprazole), a commonly used oral acid blocker.17

Propulsid® was shown to cause cardiac arrhythmias, with over 70 fatalities reported from 1993-1999, and has been removed from the US market.18

One 2012 study showed that alginate treatment was equivalent to Prilosec® (omeprazole). This is an encouraging finding, given the potential ill effects of prolonged Prilosec (omeprazole) use.19,20 (See Table of Side Effects of Common Classes of Acid-Blocking Drugs for more details.)

Most impressively, studies regularly find that alginate treatment provides relief significantly faster than drugs.17,21

What You Need to Know
Guard Against Esophageal Cancer

Guard Against Esophageal Cancer

  • The rate of gastroesophageal reflux disease (GERD), or heartburn, is rapidly rising.
  • Reflux is painful and debilitating on its own—but it is a major cause of esophageal cancer.
  • Traditional antacid treatments are used only to reduce stomach acid levels—and, in addition to having side effects, are powerless to stop the acid pocket that pushes into the esophagus.
  • When it encounters gastric acid, raft-forming alginate, which includes natural algae, forms a light but strong foam barrier—a “raft” floating on top of stomach contents and preventing acid from entering the esophagus.
  • The addition of the berry polyphenol ellagic acid further lowers acid levels in the stomach and reduces inflammation.
  • This simple combination of raft-forming alginates, carbonates, and ellagic acid offers effective defense against acid reflux—and potent protection against the risk of reflux-caused esophageal cancer.

Ellagic Acid Further Slashes Acid and Inflammation Levels

In addition to protecting the esophagus from the physical effects of acid and food reflux, it’s important to protect the stomach itself from excessive acid production and the inflammation that produces ulcers and potentially increases cancer risk.

Ellagic acid is a polyphenol found in many types of plants, such as berries and pomegranates.22,23 It is a powerful antioxidant with additional and complex properties that make it ideal for protecting stomach and esophageal health.

Like antacid drugs, ellagic acid slows the secretion of hydrochloric acid into the stomach by interfering with the molecular pump that drives hydrogen atoms into the stomach.24 Despite the name, ellagic acid is only a very mild, organic acid, with little in common with potent gastric hydrochloric acid. It directly protects the stomach’s mucous lining from damage that can lead to ulcers.24,25

Ellagic acid has been found to protect the stomach and promote ulcer healing through its favorable impact on inflammatory cytokines.22 One study clearly showed that ellagic acid shifted stomach biochemical parameters away from pro-inflammatory and towards healing profiles.23

Intriguingly, ellagic acid’s beneficial effects on the stomach lining vary depending upon the source of the inflammation. In alcohol-induced ulcers, the protective effect comes from an increase in endogenous nitric oxide, which acts as an anti-inflammatory agent.22 But in ulcers produced by the harsh arthritis drug indomethacin, ellagic acid reduces levels of the inflammatory leukotriene B4.22 And in ulcers produced by sour acetic acid (the acid in vinegar), ulcer healing was promoted by reductions in inflammatory cytokines TNF-alpha and related compounds.

Thus, in ulcer prevention, ellagic acid works both by reducing the offending factors and by strengthening the body’s natural defensive factors.22

Animal studies demonstrate that ellagic acid reduced the standard ulcer index by 59%, while accelerating ulcer healing through induction of important growth factors.23

In addition, ellagic acid appears to inhibit Helicobacter pylori, the bacterium that inevitably causes gastritis—a main cause of gastric ulcers—and which has been associated with both esophageal and stomach cancer.26,27 And indeed, one study showed that ellagic acid reduced by 21 to 55% the number of chemically-induced esophageal tumors in experimental animals.28

While we’re awaiting further proof that ellagic acid itself prevents cancer, there is strong evidence that strawberries—which are rich in ellagic acid—are powerful anti-cancer agents, as we’ll see next.

Table of Side Effects of Common Classes of Acid-Blocking Drugs


Common Names


Aluminum-containing Antacids

Maalox, Mylanta

  • Bone-Softening33,34

H2 Blockers

Cimetidine, Ranitidine, Famotidine

  • Vitamin b12 deficiency35,36

Proton-pump Inhibitors

Omeprazole, Esomeprazole

  • Vitamin b12 deficiency36,37
  • Reduced medication bioavailability38
  • Clostridium difficile-associated diarrhea38,39
  • Pneumonia37,38
  • Osteoporosis as well as vertebral and hip fracture37-39
  • Rebound acid over-secretion39

Over-the-counter antacids can be very effective against acid damage, but they come with many potentially serious side effects, especially with prolonged use. Raft-forming alginate preparations, however, are associated with none of these.

Strawberries Lower Risk of Esophageal Cancer

Strawberries Lower Risk of Esophageal Cancer  

Strawberries are loaded with powerful antioxidants, chiefly in the form of polyphenols, which block free radical formation.29 Moreover, strawberry extracts promote increases in levels of natural antioxidant systems lying dormant in the cells, triggering potent self-protection in the vulnerable stomach lining.30 Administration of strawberry extract in rats with alcohol-induced ulcers significantly reduced the animals’ ulcer index, in large part by inhibiting peroxidation of cell membrane lipids.30

Animals supplemented with strawberries show up to 56% fewer cancers after exposure to known esophageal carcinogens.31 And in those that do develop cancers, the tumors are less frequent and smaller than in control animals.

A 2012 study in humans demonstrated remarkable protection from esophageal cancer in a high-risk population, following consumption of a high-dose freeze-dried strawberry powder. These patients had known esophageal dysplasia, a pre-cancerous state. After six months of supplementation, there was a reduction in severity of the dysplasia without side effects. This visible benefit was accompanied by reductions in markers of inflammation.32

Strawberry polyphenols protect against stomach damage caused by alcohol and other damaging agents.30 Again, this effect is generally attributed to their content of antioxidants and free radical scavengers. (The strawberry intake of these human and animal subjects was vastly higher than an alginate combination could ever provide in a pill form; but including strawberry content in a formulation serves to enhance its protective activities.)

The Facts About Esophageal Cancer

The National Cancer Institute estimates that 17,990 new cases of esophageal cancer will be diagnosed in 2013, during which time the disease is predicted to cause 15,210 deaths.2

Rates of esophageal cancer are rapidly increasing, and gastroesophageal reflux is a major contributor.3,40

Esophageal cancers are most common in white men over 50, in smokers, in those who are obese, and especially in people with frequent symptoms of gastroesophageal reflux.41,42

Studies show that people with recurrent symptoms of reflux have a 7.7-fold risk of esophageal cancer, while those with long-standing, severe symptoms are at an incredible 43.5-fold risk of the disease.3


Gastrointestinal reflux is increasingly a major source of pain, suffering, and diminished quality of life—but it is also a key cause of esophageal cancer.

For years, traditional medicine operated on the simple notion that by using antacids and reducing acid levels alone, they could control the symptoms and potentially fatal consequences of acid reflux.

Raft-forming alginate creates a physical barrier “raft” to block reflux from occurring, protecting esophageal tissue from corrosive stomach contents. Alginate is clinically proven to reduce the frequency and intensity of reflux attacks, with effects equivalent to antacid medications that have substantial side effects.

The addition of ellagic acid to an alginate formulation can reduce stomach acidity and inflammation—which further protects the esophagus from the chronic inflammation that could one day trigger cancerous cells.

And strawberry extract contributes additional oxidant protection by upgrading the body’s own powerful antioxidant enzymes, with proven effects on reducing ulcer-related stomach cancer.

The simple combination of raft-forming alginates, carbonates, ellagic acid from pomegranates, and strawberry extract holds enormous potential to safely reduce painful acid reflux—and provide potential protection against cancer.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.


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