Algae: why they are part of your diet – 01/15/2024 – Balance

Have you ever wondered why your homemade ice cream is covered in ice crystals when industrial ice cream is not? Or how onion rings are all the same size, even though onions are smaller at the ends?

Or how the beer you forgot in the glass still foams half an hour later?

This is all due to seaweed extract, also known as alginate, a natural fiber, says Jeffrey Pearson, professor of molecular physiology at the University of Newcastle in the United Kingdom.

Although hidden in some foods in the West, seaweed is widely consumed in coastal areas of Asia.

And little by little they are becoming better known in the West, where they are considered a nutritional and sustainable “superfood”. But how true is this?

Some parents in the US have chosen to replace greasy, salty potato chips with seemingly healthier dried seaweed.

Despite this, highly processed seaweed snacks can be high in salt and other additives, and should be consumed in moderation.

Overweight or obesity

According to recent findings by Pearson, some species of algae may also help control weight in overweight or obese people.

This, he says, is because alginate inhibits lipase, an enzyme that helps the body digest fat, meaning it can reduce the amount of digested dietary fat by around 75%.

Pearson and his researchers used an artificial intestine to test the effectiveness of more than 60 natural fibers, measuring how much fat was digested and absorbed when consumed with common foods such as bread and yogurt.

Pearson now plans to carry out clinical trials to look at this effect when alginate is consumed as part of a normal diet and hopes that his research will lead to him introducing more alginate into foods such as bread to help people control their weight.

Seaweed doesn’t just help with weight loss. Large studies in Japan found a correlation between daily seaweed consumption and lower rates of heart disease compared to those who did not eat seaweed, and a lower risk of stroke in men.

However, a recent review of 25 studies looked at the health benefits of consuming seaweed.

It turned out that many studies showing positive health outcomes correlated with a diet rich in seaweed were carried out in people with health problems such as obesity and type 2 diabetes, rather than in the general population.

“In healthy individuals, the algae most likely does not generate any health benefits”, says the main author of the article, João Pedro Trigo.

However, eating between 5 and 10 grams of seaweed per day can provide nutritional benefits thanks to the fiber and nutritional content of seaweed, Trigo adds.

Still, there is very little known about how processing and fermentation affect how the body absorbs nutrients from algae.

Potential risks

There are also some concerns surrounding the potential risks of arsenic, lead and iodine found in seaweed.

Some species of algae may contain more arsenic than others, says Florent Govaerts of the Norwegian food research institute Nofima.

“You can have the same species and one will contain a lot more arsenic than the other, depending on where it’s produced,” he says.

Arsenic levels in algae often vary depending on the arsenic content of the water in which they are grown.

But while there are real concerns about the extent to which our diet can expose us to heavy metals, Alec Watt, director of macroalgae exploration Green Ocean Farming in the UK, says all algae sold for human consumption is tested first.

“There are processes to control algae,” he explains.

The type of algae that contains arsenic is organic, which the body eliminates through urine, says Pearson.

Seaweed can also contain high levels of iodine, but again, the amount depends on the species of seaweed.

“You can get a lot of iodine if you eat a lot of seaweed,” explains Ingrid Undeland, professor of Food Science and Nutrition at Chalmers University of Technology in Gothenburg, Sweden.

“These are relatively small amounts before reaching the approximate recommended daily intake. It also depends on the species and the possible presence of metals or unwanted elements in the water, which is a difficult message to convey”, he says.

Too much iodine can cause thyroid problems in some people, and more immediate side effects include nausea and vomiting.

Additionally, studies have shown that various types of processing – including washing, blanching, boiling, soaking, drying and fermenting – can reduce the amount of iodine in some species of algae.

Particular flavor

However, the question of taste remains. Although seaweed extract doesn’t taste like anything, Pearson says, he tested it on whole seaweed and found mixed results.

“We found that people don’t like it and don’t ask for more,” he says.

Studies show that some people may be more skeptical of foods they are unfamiliar with.

However, researchers have recently discovered evidence that, contrary to popular belief, seaweed used to be an important part of the diet of ancient Europeans during the transition to agriculture.

Researchers examined dental tartar from 74 people across Europe and found evidence that people ate seaweed during the Mesolithic period, about 8,000 years ago, and the Neolithic period, 6,000 years ago.

“No one had found direct evidence of seaweed consumption before prehistoric archaeological records. It was very unexpected,” says Karen Hardy, co-author and professor of prehistoric archeology at the University of Glasgow.

“We have preconceived ideas about what food is like in Europe and seaweed is not the first thing that comes to mind,” he says.

Perhaps, then, getting used to the taste of seaweed is not such a challenge.

The reputation of algae

However, there may be some confusion about how to eat seaweed and incorporate it most efficiently into our diet.

Watt recommends chopping dried seaweed and sprinkling it on food as a way to season it. But while he’s passionate about the benefits of seaweed, he’s not optimistic about seeing frozen seaweed in supermarkets anytime soon.

“We need a celebrity chef to promote them,” he says.

Despite the apparent lack of information about seaweed, its reputation that it brings numerous health benefits prevails.

When Govaerts conducted a survey to measure knowledge and understanding about seaweed, he found that people in Norway and the United Kingdom, for example, generally have very little knowledge about the subject, other than to believe that it is quite healthy and sustainable.

But to further complicate the seaweed message, researchers argue that it’s not as simple as saying seaweed is healthy or unhealthy, safe or dangerous, because there are so many species.

Referring to all algae species simply as “algae” is like referring to all legumes simply as “legumes,” says Govaerts.

Seaweed species don’t just vary in taste: their nutritional profiles are also very different. And the nutritional value of algae not only varies from species to species, but also depending on the water in which it is grown, says Undeland.

“We should stop talking about ‘algae’, because they are very different in the way they relate to each other and what they contain. Some may be healthier than others and contain more protein,” says Undeland. “There are 145 edible species and six produced in large quantities.”

It remains to be seen whether seaweed – or certain species of seaweed – will become more ingrained in the Western diet in the near future.

There are still many unknowns about iodine and arsenic contamination, but the European Food Safety Authority monitors the growing popularity of seaweed to better control this issue.

But celebrity chef or not, seaweed is associated with many health benefits and could become a more widespread and healthy addition to the Western diet.

This article was published on BBC Future. Click here to read the original version.