A ‘superfood’ commonly found in restaurants and grocery stores may be able to prevent an infection with a common, and debilitating, virus.
Researchers in Australia have found that compounds in brown and green seaweed stop an infection with norovirus, a highly contagious stomach bug that causes nausea and vomiting so forceful sufferers sometimes crack ribs, in its tracks.
Normally, the virus, which is spread by touching surfaces contaminated with the bacteria from an infected person, binds to sugars on the surface of gut cells to enter them and cause an infection.
But in lab tests, scientists found that complex carbohydrates from seaweed mimicked the shape of these sugars and caused the virus to bind to them instead.
The higher the concentration of the seaweed, available in grocery stores for about $0.60 a pack, the more virus it trapped — in some cases, leaving almost none to infect human cells.
Researchers said their results showed seaweed had ‘promising inhibition capacities’ against norovirus, which currently has no preventative measure, and may even be a possible alternative to a vaccine.
In previous cases, shots targeting noroviruses have failed because the virus mutates rapidly, allowing it to skirt around vaccine-triggered immunity.
Researchers say that seaweed could help to curb a norovirus infection (stock image)
About 19 to 21 million Americans are sickened by norovirus every year, estimates suggest, while 900 die from the infection.
Normally, the infection clears up on its own in one to three days. To treat it, doctors recommend patients get bed rest and drink plenty of fluids. In severe cases, however, it can cause dangerous dehydration that requires hospitalization.
Doctors say that those under five years old and older adults are particularly at risk because they have a weaker immune system.
In the study, which was published as a letter in Microbiology Spectrum, scientists tested how to block norovirus from entering gut cells.
Typically, the virus would bind to sugar molecules called histo-blood group antigens (HBGAs), found on the wall of the cell, to gain access and cause an infection.
But the scientists had noted that two complex carbohydrates in seaweed, fucoidan and ulvan, mimicked the shape of HBGAs.
In their lab study, they also found that the complex carbohydrates worked across multiple strains of norovirus, with variants including GII.4, the most common form of the virus, and GII.17, also binding to the seaweed instead of gut cells.
Scientists emphasized, however, that research was in the early stages and that more work was needed to prove seaweed could prevent an infection.
Norovirus is a common winter bug that infects about 19 to 21 million Americans every year. It is also linked to some 900 deaths annually (stock image)
Shown above is a pictured of deep-fried seaweed (stock image)
Limitations included that the study was not carried out in humans. Conditions in the gut could cause the virus or seaweed to behave differently.
It was also unclear how much seaweed is needed to avoid an infection.
Seaweed can be a part of a balanced diet, and is considered a superfood because it is fiber- and nutrient-dense while being very low in calories, sugar and fat.
But, despite this, some experts suggest that people should not eat seaweed more than two or three times per week.
This is because some portions contain high levels of salt, with the average American told not to consume more than a teaspoon of salt per day, and higher levels of iodine.
High salt levels can cause high blood pressure, and raise the risk of conditions including a stroke, heart attack and kidney damage. High iodine levels can interfere with the thyroid, a vital organ that regulates the body’s metabolism.
In recent years, seaweed has found new popularity amid suggestions that it could be an excellent food for weight management. Some experts say its nutrient profile can help to curb appetite for longer.
