By Silvia Alunni – Hague Corporate Affairs

Fats have been under the spotlight for many years, as their high consumption is correlated with health-related issues such as obesity and cardiovascular diseases. Lately, research unfolded the benefits of certain types of ‘good fats’, shifting the perspective mass consumers had on this nutrient. The distinction among different types of fat has been remarked by relevant international organisations: for instance, the WHO advises a maximum fat consumption equal to 30% of the daily energy intake, with preference for mono-and polyunsaturated fatty acids, while suggesting limiting the consumption of saturated fats and almost eliminating that of trans-fats[1]. Do dietary fats affect the gut microbiome? This blog addresses this question using plant-based spreadable fats as an example. After exposing the main scientific findings related to the impact of plant-based spreadable fats (e.g. margarine) on the gut microbiome, we look at how research could impact the health profile of these products.

First of all: what are plant-based fats? EU legislation defines them as ‘products in the form of a solid, malleable emulsion, principally of the water-in-oil type, derived from solid and/or liquid vegetable and/or animal fats suitable for human consumption, with a milk-fat content of not more than 3 % or the fat content’. These products are categorised according to their percentage of fat content, margarine being the product with the highest one (between 80 and 90%). The types of fats contained in the product are particularly relevant to the microbiome, as different dietary fats may have a diverse effect on our gut[2].

The most critical types of fat in plant-based spreads are trans-fatty acids – unsaturated fats resulting from the hydrogenation process – (TFAs) and saturated fats. Studies have remarked a correlation between a high intake of such fats with a decrease in microflora diversity and an increase in those bacteria promoting metabolic inflammation[3]. As a consequence, a diet rich in saturated fats -typical of the current Western lifestyle- has also been linked to an augmented risk of inflammatory bowel diseases and insulin resistance, caused by a change in the balance of gut bacteria that triggers a response from the immune system [4],[5].

Plant-based fats also contain a remarkable amount of monounsaturated and polyunsaturated fats, also known as the ‘good fats’. The former showed to have a limited yet healthful impact on the microbiome by stimulating, among others, bacteria improving intestinal barrier functions.[6] The latter, such as Omega 3 fatty acids, has proven beneficial to human gut composition, favouring a diverse and variegated environment for the intestinal flora, with a consequential improvement in overall health[7].

Can research and innovation projects like CIRCLES help making plant-based fats healthier? The question is a challenging one, since these products are the result of several production stages, in which the original ingredient – e.g. olives, rapeseeds, soy, palm – undergoes many processes that substantially modify the bacterial profile of the food. Research could act at the farming stage by optimising the microbiome composition of the food, with a view to providing high-quality ingredients to the first stage of the production process. In a long-term perspective, it would be worth taking a step-by-step approach along the whole plant-based fat value chain, by first investigating how bacteria balance changes between the whole food and its (un)refined oil. At a later stage, synergies with the plant-based fat industry can be envisaged to explore whether microbiome modification (combined with innovation in production processing) could help to lower the content of saturated and trans-fats in the final product.

In conclusion, plant-based spreadable products encompass a wide range of fats, with both a negative (saturated and trans-fats) and beneficial (mono-and polyunsaturated fats) impact on the gut microbiome. Due to the highly processed nature of these products, it is challenging to envisage a possible contribution of microbiome research, which is mainly focused on whole foods at this stage. Yet, it can be a long-term objective for future research projects to investigate the potential of microbiome composition and modification along the whole product supply chain, which can be carried out alongside technological innovations set forth by industries wanting to improve the health profiles of their products.

 

Image credit: Marko Blažević via Unsplash

 

[1] WHO, Healthy Diet. Retrieved from: https://www.who.int/news-room/fact-sheets/detail/healthy-diet

[2] Wolters, M., Ahrens, J., Perez, M. R., Watkins, C., Sanz, Y., Benítez-Páez, A., … & Günther, K. (2018). Dietary fat, the gut microbiota, and metabolic health–A systematic review conducted within the MyNewGut project. Clinical Nutrition.

[3] Singh, R. K., Chang, H. W., Yan, D., Lee, K. M., Ucmak, D., Wong, K., … & Bhutani, T. (2017). Influence of diet on the gut microbiome and implications for human health. Journal of translational medicine, 15(1), 73.

[4] Saturated fats change gut bacteria and may raise risk for Inflammatory Bowel Disease. Retrieved from: https://blogs.scientificamerican.com/observations/saturated-fats-change-gut-bacteria-and-may-raise-risk-for-inflammatory-bowel-disease/

[5] Alcock, J., & Lin, H. C. (2015). Fatty acids from diet and microbiota regulate energy metabolism. F1000Research, 4(F1000 Faculty Rev).

[6] Alcock, J., & Lin, H. C. (2015). Fatty acids from diet and microbiota regulate energy metabolism. F1000Research, 4(F1000 Faculty Rev).

[7] Menni, C., Zierer, J., Pallister, T., Jackson, M. A., Long, T., Mohney, R. P., … & Valdes, A. M. (2017). Omega-3 fatty acids correlate with gut microbiome diversity and production of N-carbamylglutamate in middle aged and elderly women. Scientific reports, 7(1), 11079