Greg Potter, MS, PhD
By now, you’ve probably heard people touting reasons why consuming edible insects (entomophagy) is a good idea. Perhaps you’ve tried them or even routinely include them in your diet. It’s something that I’ve always been open to, and when I tried crickets I was impressed by how good they actually taste. Obviously, crickets aren’t as moreish as roast lamb, but the flavor is wholesome and nutty, and I imagine the texture lends itself well to many dishes. I knew that many insects are unusually dense sources of protein and fiber, so I wanted to learn more. In this blog, I’ll share the highlights of what I found, focusing on insect protein.
Why Eat Insects? A Global Perspective
If you cringe at the mere prospect of eating insects, consider these facts: About 2 billion people on our planet habitually consume insects, and these individuals eat more than 2,000 species of insects. Furthermore, many people continue to forage for insects in the wild, and it seems that humans have been doing so for millennia (1). So, whereas eating insects isn’t (yet) the norm in continents such as Europe and North America, it might be more common elsewhere than you anticipated. Many people eat insects, but why is this important?
United Nations researchers currently estimate that the world’s population will reach 9.8 billion by 2050. Relying on our current staple animal protein sources to nourish so many people may not be wise, for consequences such as greenhouse gas emissions and water use may produce unsustainably severe strain on ecosystems. Nowadays, roughly 1 billion people suffer from protein energy malnutrition worldwide, and the results of this are tragic. If protein supply doesn’t match demand, this number will only increase (2).
The idea of increasing global insect consumption (relative to other protein sources) to counter these trends makes sense for several reasons. First, some insects are about 50% protein by weight – more than dairy, eggs, fish, or meat – and a higher proportion of the mass of insects is edible than conventional livestock. Next, insects procreate far more rapidly and convert what they eat into body mass more efficiently than conventional livestock. Last, farming insects may require less land and water, while also producing lower quantities of greenhouse gases than conventional livestock (1). Yep, that’s a pretty strong portfolio. But as somebody who really cares about personal health I’m not yet won over… what about the nutrient profiles of insects?
Are Insects Good Sources of Protein?
Insects vary between about 7% and 48% protein by weight, but obviously these numbers rise when they are assessed on a dry matter basis. There is remarkable variation in protein content within species of the same order. Within the order Orthoptera (which includes crickets, grasshoppers, and locusts), for example, protein ranges from as little as 6% to as much as 77% of dry matter. But there is also substantial variability within species, depending on factors such as insect developmental stage, feeding, and season of assessment (1).
Another noteworthy consideration is that the tough exteriors (exoskeletons) of insects contain chitin. Chitin is fibrous, but like protein it contains nitrogen. Because the protein content of foods is generally determined by measuring their nitrogen content, nitrogen in chitin likely leads to overestimation of insect protein content. This exaggeration is probably amplified by other nonprotein nitrogen sources in insects too, such as free amino acids (1).
Insect Protein Composition
Now, a key concept in dietary protein metabolism is that the effects of proteins partly depend on their amino acid building blocks. Because our bodies cannot synthesize all amino acids, we need certain quantities of specific (indispensable) amino acids from our diets. Vegans are all too familiar with this, for few plant proteins contain sufficient concentrations of all amino acids. Cereals, for instance, are typically low in lysine, threonine, and tryptophan, whereas legumes are low in cysteine and methionine. A simple solution for vegans is to pair cereals with legumes at the same meal. (There’s a reason Jamaicans love rice and peas.) So, the amino acid composition of protein sources is important.
There’s significant variation between insects in their amino acid profiles. Insects from the orders Coleoptera (beetles), Hymenoptera (includes ants, bees, and wasps), Lepidoptera (butterflies and moths), and Orthoptera (which I mentioned earlier) typically meet adults’ amino acid needs, and the amino acid profiles of these organisms are comparable to high-quality proteins like beef, eggs, and milk (1). The same is not true for other insect orders that have been studied, although it may be that combining insects from different orders within a meal overcomes the amino acid inadequacies of individual insects. Similarly, including insects from certain orders with complementary cereals or legumes may result in a superior complement of amino acids.
Another point that I’ll make is that the “needs” of adults to avoid malnutrition may not be optimal. The process of accruing skeletal muscle exemplifies this. Fundamentally, your muscle mass depends on the balance between how much muscle protein your body synthesizes and how much it degrades. Because muscle protein synthesis is far more amenable to change than muscle protein degradation, researchers generally focus on the factors that influence synthesis. (Another consideration is just that measuring muscle protein breakdown is harder.) Of all amino acids, leucine is unique in its ability to trigger muscle protein synthesis, and a certain amount of leucine is probably needed at each meal to maximize this construction process. Milk proteins are a mainstay in bodybuilders’ supplement cabinets in part because of their high leucine content. Interestingly, several orders of insects (Coleoptera, Hymenoptera, Isoptera (termites), and Orthoptera) have leucine contents similar to some milk proteins (1).
Insect Protein Digestibility
The last thing that I’ll mention is that the composition of protein is inconsequential if the protein can’t be digested. For this reason, scientists sometimes measure the difference in amino acid levels across the small intestine to assess digestibility. Such studies are costly and technically tricky though, so alternative methods that don’t involve live animals have been developed. Studies of protein digestibility have reported large differences between insect proteins, and head-to-head work found that termite protein is much less digestible than casein, a milk protein. This may partly be because proteins are bound up by insect exoskeletons though, for when chitin is removed digestibility is much improved.
The Future
I hope that this blog has persuaded you to seriously consider including insects in your diet at some point. A variety of edible insects can be easily ordered online now, including ants, chapulines, crickets, locusts, mealworms, and silkworms. A good place to pick these up is Crunchy Critters. But you needn’t go for whole insects, for there are now many insect protein products. Many people love EXO protein bars, for instance. Others enjoy insect protein powders, such as those made by CRIK nutrition. These powders combine cricket protein with vegan protein sources. Purists searching for unadulterated insect protein sources can try flours, like those made by Cricket Flours. And if you opt for flours or powders, why not use them as a protein source in smoothies? humanOS recently released smoothie recipes for Pro users, each of which details health benefits of the ingredients. Instead of whey, try using insect protein sources in these and see how you get on! Alternatively, you can combine insect sources with other protein sources, if you prefer.
The scientific research on eating insect protein is so paltry at the moment that I understand if you choose to await more studies. We just don’t know much about the metabolic consequences of insect protein intake compared to that of animal and plant proteins. This said, there are several reasons to assume that insects are very healthy foods. It’s probably occurred to you that it is of course myopic to only consider amino acids, for insects contain a diversity of other compounds that influence health too. As just one example of this, consuming chitin appears to induce numerous anti-aging effects, partly through its potent antioxidant actions (3). And the macronutrient profiles of insects generally appear to be a dieter’s dream – insects are packed with protein and fiber.
Future research on how to optimize insect production will be valuable. If we’re selfish for a few seconds and only consider our own health, studies of how insect feed influences insect nutrient profiles might be fruitful. In addition, it will be interesting to see work that clarifies the results of combining different insect proteins, for there’s reason to think that this strategy will be advantageous. I’m also excited at the advances being made in producing other dietary proteins, such as efforts to synthesize meat in the lab.
I don’t want to sound cheesy, and I’m not a fan of preaching. However, we live on a beautiful planet that teems with wonderful beings. Various forces threaten the integrity of this state, but the good news is that we can act to move the dial in the right direction. As my awareness of this has grown, I’ve become increasingly conscious of the many things I routinely do that jeopardize the natural world. Going forward, eating insects now and then doesn’t seem too much to ask.
Key Takeaways
- The world’s population is growing, and this requires new ways to feed people.
- Many people consume insects, and humans have done so for a long time.
- Insects are generally rich in protein, and many appear to have amino acid profiles comparable to animal proteins.
- Very little is known about the metabolic consequences of eating insects.
- Many insect protein products are available, and more and more people are enjoying them.
References
- Churchward-Venne TA, Pinckaers PJM, van Loon JJA, van Loon LJC. Consideration of insects as a source of dietary protein for human consumption. Nutr Rev. 2017;75(12):1035-1045.
- Wu G, Fanzo J, Miller DD, Pingali P, Post M, Steiner JL, Thalacker-Mercer AE. Production and supply of high-quality food protein for human consumption: sustainability, challenges, and innovations. Ann N Y Acad Sci. 2014;1321:1-19.
- Kerch G. The potential of chitosan and its derivatives in prevention and treatment of age-related diseases. Mar Drugs. 2015;13(4):2158-82.