Could Red Marine Algae Help You Suppress Viral Infections?

Could Red Marine Algae Help You Suppress Viral Infections?

With a “tripledemic” upon us, this winter has already come to rival some of the worst cold and flu seasons on record. Amid this nasty collision of the flu, COVID-19, and respiratory syncytial virus (RSV), many of us are left wondering, what more can we do to stay safe? And as these three major respiratory viruses surge at once, we find ourselves asking, what else can we do to protect ourselves against common viral infections? Perhaps, there is a simple solution.   


What Are Red Marine Algae?

Red marine algae have been used for centuries in Traditional Chinese Medicine, renowned for their benefits in treating certain types of infections.1 Red marine algae are a rich source of protein, vitamins, trace minerals, and fiber.2 They are associated with a range of health benefits, including anticancer, antidiabetic, antioxidative, and antiviral effects.3 How do these marine gems work? Could they be effective against some of the most concerning viruses we commonly face today? Let’s dive into the details.


What Is Gigartina skottsbergii?

One strain of red marine algae is of particular benefit for promoting natural immune protection against viruses—Gigartina skottsbergii. This highly active strain of red marine algae is a potent source of sulfated polysaccharides—complex sugars that contain sulfur. Sulfated polysaccharides have well-known antiviral properties and possess the ability to inhibit viral replication.4 Sulfated polysaccharides have shown inhibitory effects on a range of viruses, including oral herpes, genital herpes, influenza, HPV, and HIV.5


How Do Red Marine Algae Work? 

The sulfated polysaccharides abundant in red marine algae promote protection from viruses in a variety of ways. The antiviral properties of sulfated polysaccharides directly inhibit many viruses. They function to block the entry of viruses into their target cells. They also inhibit the viral transcription and replication process within host cells.6 Further, sulfated polysaccharides help to activate the body’s own defenses against viruses. They are believed to ramp up the production of interferons, which are key proteins within the immune system.1 Interferons ‘interfere’ with viral infections by alerting the rest of the immune system to them. They trigger the immune system to prevent viruses from replicating, thereby, stopping their proliferation.7


The Herpes Simplex Virus

Infection with the herpes simplex virus (HSV) is extremely common. HSV is categorized into two types: HSV-1 and HSV-2. HSV-1 mainly causes oral herpes (which leads to cold sores), but it may also lead to genital herpes. HSV-2 is a sexually transmitted infection that causes genital herpes.8


Both oral and genital herpes tend to be asymptomatic, with many people being unaware that they are infected. But, for some, these infections may lead to periodic outbreaks of painful blisters. Medication may reduce the severity and frequency of symptoms. However, once infected, a person will have the herpes simplex virus for the rest of his or her life.9


Cold Sores 

Despite their name, cold sores are not caused by the common cold. Cold sores, or fever blisters, typically result from an oral herpes infection due to the herpes simplex virus type 1 (HSV-1).9 It is estimated that 50-80% of U.S. adults are currently infected with oral herpes.10 HSV-1 may also lead to genital herpes.11


Genital Herpes

Genital herpes is a sexually transmitted infection caused by the herpes simplex virus type 2 (HSV-2). Though often asymptomatic, for some, it may cause blisters and open sores in the genital area. Approximately 1 in 6 people in the U.S. between the ages of 14–49 carry the virus for genital herpes.12


Are Red Marine Algae Effective Against the Herpes Simplex Virus?

Research indicates that the strain of red marine algae known as, Gigartina skottsbergii, is highly effective against the herpes simplex virus, both HSV-1, which causes cold sores, and HSV-2, which causes genital herpes.13 Gigartina skottsbergii contains a high concentration of sulfated polysaccharides that inhibit viral replication of the herpes simplex virus. As such, the sulfated polysaccharides in Gigartina skottsbergii are potent inhibitors of both HSV-1 and HSV-2.14, 15



Shingles is a condition marked by a painful, blistering red rash that wraps like a band across one side of the face or body. It causes intense itching, burning, and shooting pain. Other symptoms may include fatigue, nausea, fever, or headache. Only people who have been infected with chicken pox are susceptible to shingles. According to the CDC, about 1 in 3 people in the U.S. will develop shingles at some point in their lifetimes.16

Shingles is caused by a virus known as the varicella zoster or herpes zoster virus. When this virus first infects the body, it causes chickenpox. Once chickenpox clears, the virus moves into the nerve tissues near the spinal cord and brain. It may remain dormant in these nerve cells for years. But the virus can reactivate, possibly even decades later. It can ‘reawaken’ and attack the nerve fibers that feed the skin, which leads to shingles. We don’t fully understand what causes the virus to resurface this way. It may be that susceptibility to the virus increases as innate immune defenses weaken. Those over the age of 60 or with compromised immune systems are at an increased risk of developing shingles.17

The shingles rash usually clears up within two to four weeks. Some people may require medical intervention such as antiviral medication or steroid ointments. For some, shingles may cause ongoing nerve pain called post-herpetic neuralgia. Currently, there are no treatments available to eliminate the herpes zoster virus from infected individuals. The CDC recommends vaccination for the prevention of shingles.16


Are Red Marine Algae Effective Against the Herpes Zoster Virus?

While several effective treatments are available for the herpes zoster virus, including vaccination, researchers continue to search for alternatives for those who suffer from vaccine-resistant strains of the virus. Research is exploring the use of red marine algae as an alternative for those who suffer from recurring flare-ups with shingles, despite vaccination. A recent study finds that the sulfated polysaccharides in red marine algae can block different stages of the herpes virus replication cycle, including penetration into host cells. This study concludes that sulfated polysaccharides are a beneficial natural agent that effectively inhibits infection by the herpes zoster virus.18



So, what can we do to naturally boost immunity to common viruses? Supplementing our diets with red marine algae may be the answer. Research indicates that red marine algae have the potential to help suppress many types of viral infections, including those from the herpes simplex virus, the herpes zoster virus, and many others. The sulfated polysaccharides abundant in red marine algae effectively block the entry of these viruses into their target cells and inhibit their viral replication within host cells. They also stimulate the immune system to increase the production of interferons, further helping to ward off viral infections. These effects may be particularly beneficial for those with compromised immune systems or those who may experience recurring outbreaks of oral herpes, genital herpes, or shingles. Emerging research further indicates that algal metabolites show the potential to suppress many types of common viral infections, including those that cause cold sores, genital herpes, HPV, influenza, and COVID-19.19



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