BY: DR. JASON BUSH
The newest version of Canada’s Food Guide has prompted reactions for several reasons. Firstly, complex advice surrounding portions and servings found in the previous iteration was replaced by the presentation of a plate divided into portions of different types of food. This image conveys perhaps the most important point: Make sure that half your plate is made up of a combination of fresh and prepared fruits and vegetables, and that protein and carbohydrate sources each make up only a quarter of your plate. The health professionals who authored the Food Guide believe that the most effective way to combat unhealthy eating is not to focus on portion size but rather to ensure that half of each meal or snack is mostly non-starchy vegetables.
Another surprising aspect of the new Food Guide is the recommendation that protein sources come largely from plant rather than animal sources. Many people have interpreted this message as an attack on the meat industry, focusing on connections between unhealthy fats and the sodium and chemicals present in preserved meat. However, increasing your intake of plant-based protein sources provides the added benefit of increasing your dietary fibre, something that simply cannot be obtained from animal-based protein sources.
A final point emphasized by the new Food Guide is the preference that carb-heavy foods come from whole grain sources. Milling grains into white flour removes most roughage, which creates an appealing texture when used in baking and the production of pasta. However, foods made with processed flour are quickly converted to sugar when digested, leading to rapid spikes in blood glucose. Complex carbohydrates, in which digestible carbs are retained within fibrous, protein-containing cell walls, are digested more slowly and have nutritional value beyond simple calories.
What do these three points emphasized by Canada’s Food Guide have in common? Increasing fruits and veggies, seeking plant-based proteins, and choosing whole grain carbohydrates will all effectively increase the amount of dietary fibre you consume. While the Food Guide does not (yet) recognize prebiotic material as being an important subset of dietary fibre, it’s clear that the nutritional science driving these revisions is certain to improve the abundance of prebiotics in our diet, translating to improved gut health.