In many cultures around the world, insects and arachnids form a normal part of a person's diet. In the United States and Europe, however, we tend to regard such "delicacies" with mistrust. Can scientific evidence suggesting that insects are more healthful and nutritious than other foods change our minds?
Edible insects have the highest market value in Asia-Pacific regions, according to recent reports. However, the same reports indicate that their value is on the rise in the United States.
Most people in Western countries may think that insects and other creepy crawlies, such as spiders or scorpions, have no place in their daily meals because they have a bad rap as scary house intruders. However, scientists suggest we should be more open minded about including such critters in our diets.
For example, only last year, a clinical trial from the University of Wisconsin-Madison found that eating crickets could improve a person's gut microbiome.
In a new study, investigators from the University of Teramo in Italy now show that insects have a high content of antioxidants, which are natural substances that help maintain cellular health.
This could mean that insects might do a better job of supporting our health than fruit and vegetables, potentially becoming the next superfood — though this is a term that some nutritionists tend to eschew, arguing that it can be misleading.
"At least 2 billion people — a quarter of the world's population — regularly eat insects," notes the study's lead author Prof. Mauro Serafini. However, he admits, "[t]he rest of us will need a bit more encouragement."
So far, the researchers have conducted their investigation in vitro, and they report their findings in a study paper that appears in the journal Frontiers in Nutrition.
Crickets for an antioxidant kick?
With the current study, researchers have aimed to quantify for the first time, the potential healthfulness of edible insects and other edible invertebrates by assessing their content of antioxidants.
"Edible insects are an excellent source of protein, polyunsaturated fatty acids, minerals, vitamins, and fiber. But until now, nobody had compared them with traditional functional foods, such as olive oil or orange juice, in terms of antioxidant activity," notes Prof. Serafini.
The team procured and analyzed 12 different edible insects, as well as two types of invertebrates. These were: mealworms, buffalo worms, palm worm larvae, evening cicadas, black ants, African caterpillars, silkworms, grasshoppers, crickets, mini crickets, giant water bugs, Amazonian giant centipedes, Thai zebra tarantulas, and black scorpions.
To find out the insects and arachnids' antioxidant content, the researchers ground them and then separated them into fat-soluble content and water-soluble content after having removed any inedible parts, such as wings or stings. Finally, they tested each of the edible parts to see how rich they were in antioxidants.
Prof. Serafini and team found that, in some cases, insects beat oranges — which are high in antioxidants — and other healthful foods.
In particular, water-soluble extracts from grasshoppers, silkworms, and crickets have five times the antioxidant power of fresh orange juice, which nutritionists value for its high antioxidant content.
Moreover, the fat-soluble content of silkworms, evening cicadas, and African caterpillars have twice the antioxidant power of olive oil.
When it comes to the total level of polyphenols (antioxidants), the researchers note that grasshoppers, black ants, and mealworms pack the highest amount. At the same time, Thai zebra tarantulas, black scorpions, and giant water bugs have little to offer.
"There's a clear trend: the vegetarians [strictly plant-eating invertebrates] have markedly higher antioxidant capacity," says Prof Serafini.
Superfoods or...lost in digestion?
The researchers explain that their current findings are very promising; if insects really are better sources of nutrients, this could help address the global problem of food sustainability, they argue.
"Our results show that edible insects and invertebrates are an optimal source of bioactive ingredients and of high quality protein, minerals, vitamins, and fatty acids, together with a low environmental impact, highlighting their importance as sustainable novel foods under a nutritional, functional, and ecological point of view," the scientists write in their paper.
However, the team also cautions that they have not yet tested the effectiveness and safety of insect-derived antioxidants in humans.
"The in vivo efficiency of antioxidant-rich food is highly dependent on bioavailability [effectiveness of a substance once it enters the body] and the presence of an ongoing oxidative stress [a key factor that contributes to cellular damage]," explains Prof. Serafini.
The next step for the researchers will be to confirm whether eating insects will really offer a healthful antioxidant punch to humans, or whether the best parts of these edible critters are lost in digestion.
However, Prof. Serafini and team also argue that insect farmers might be able to feed critters suitable for human consumption a diet that may render them more healthful.
"In the future, we might also adapt dietary regimens for insect rearing in order to increase their antioxidant content for animal or human consumption."
Prof. Mauro Serafini