Overcoming the omega 3 bug downside
Insects are nutritionally attractive as they are rich in protein, vitamins, minerals and low in calories. Yet, bugs have higher omega-6 to omega-3 ratios than those seen in the junky Western diet! Should we forget about insects then? Not at all, as this problem has a very simple food fix...
Despite their 'gross' appearance, insects have been proposed as the protein source to feed the rapidly expanding world population. Unlike livestock, insect farming costs are relatively low at both an economic and environmental level.
You see, insects occupy far less land, eat less and produce substantially less waste than livestock. So, from a sustainability point of view, insects’ rule.
In addition, bugs are a fantastic protein source, offering higher amounts of certain micronutrients compared to commonly consumed animal meats.
For example, insects are especially rich in calcium and iron, with the iron content in crickets and honeybees being 180% and 850% greater than that of beef.
Another bug bonus is their low-calorie content compared to meat, making them especially attractive for those trying to lose weight, while wanting to retain their muscle mass.
Moreover, insects offer insoluble dietary fibre in the form of chitin, improving bowel function and reducing the risk of colorectal cancer. This is a key distinguishing factor from meat, which has zero fibre.
From all I mentioned, insects are very attractive from a sustainability and nutritional point of view, but they come with the downside of having a very high omega-6 to omega-3 ratio (n-6/n-3 ratio).
Why is this problematic?
Diets that provide very little omega 3s and excessive amounts of omega-6 fats are associated with several health issues in humans, including cardiovascular disease, cancer and autoimmune diseases.
Both omega-6 and omega-3 fatty acids are crucial for the body and must be consumed in the diet. However, since omega-3s are anti-inflammatory while omega-6s favour inflammatory pathways, it is important to have a tight ‘omega balance’ that will prevent the body from running into a constant inflammatory state associated with poor health outcomes.
The ideal n-6/n-3 ratio for optimal health outcomes is 5 or less, but the typical western diet bumps up this ratio to 16! Surprisingly, this ratio is even higher for bug species, being 18 in black soldiers, 22 in mealworms and 36 in house crickets.
While this is concerning, a recently published paper showed that the n-6/n-3 ratio of insects can be easily improved.
Quite simply, through diet.
If you ever wanted to improve your n-6/n-3 ratio, you would just incorporate more omega-3 rich foods into your diet, or reduce your total omega-6 intake, or use both strategies.
Well, it seems that insects are no different to humans in this aspect...
In this study, the researchers assessed whether adding flaxseed oil (a source of omega-3) on top of a standard insect diet could substantially improve the n-6/n-3 ratio of house crickets, lesser mealworms and black soldier flies.
All these insects were fed a standard diet containing approximately 4% fat per kg of insect feed, of which 2.5% was alpha-linolenic acid and 0.5% EPA (both are omega-3s).
Then, the researchers divided the insects into 4 groups based on the amount of flaxseed oil that was added to their standard feed: 0, 10, 20 or 40 g of flaxseed oil (0, 1, 2, or 4%) per kg of insect feed were made for each treatment group.
So, what kind of changes occurred to the n-6/n-3 ratios of the three investigated insect species with the addition of flaxseed oil?
In short, MASSIVE reductions!
The inclusion of 2% of flaxseed oil was enough to bring the n-6/n-3 ratio down from 36 to 4 in house crickets, and from 22 to 4 in lesser mealworms. Meanwhile, 1% of flaxseed oil sufficed to reduce the n-6/n-3 ratio in black soldier flies from 18 to 3.
Moreover, the reduction in the n-6/n-3 ratio for all insect species was dose-related, with the greatest reductions happening with the addition of 4% of flaxseed oil. However, since lower doses of flaxseed oil successfully reduced the n-6/n-3 ratio to what is deemed healthy in humans, it does not appear necessary to feed insects higher quantities.
What’s so exciting about this study is that it shows that the n-6/n-3 profile of insects can be easily improved, making them an even healthier protein source.
Even better, the addition of flaxseed oil at different quantities did not affect the survival, development time, live weight or dry content matter of the three species. In other words, insects grew just as well with the modified diet as with their standard diet, but with the added benefit of being nutritionally healthier.
To sum up, insects that are produced on standard commercial diets have the downside of having extremely high n-6/n-3 ratios. Fortunately, tweaking the standard bug diet with flaxseed oil is a very simple and effective solution to overcoming this problem and making insects an even healthier protein source.
Payne, C.L., Scarborough, P., Rayner, M. & Nonaka, K. (2016). Are edible insects more or less 'healthy' than commonly consumed meats? A comparison using two nutrient profiling models developed to combat over- and undernutrition. European journal of clinical nutrition, 70(3), 285–291.
Oonincx, D.G.A.B., Laurent, S., Veenenbos M.E. & van Loon J.J.A. (2019). Dietary enrichment of edible insects with omega 3 fatty acids. Journal of Insect Science. Doi: 10.1111/1744-7917.12669.
This post was written by Juan Girones, Medical Writer at Havas Life Medicom.
You can read more of his work on his blog Nutrisphere on Medium: Precise and up-to-date nutrition and medical information.