Food & Health

  • Date Posted: 14 April, 2020

Fermented and plant based food will boost your microbiome and immune system

By Angela Schaefer

Fermented vegetables in your diet can improve your immune system.

Even though we have to protect ourselves through hand washing and social distancing, from contracting Covid-19 during this lockdown period, we can also assist by giving some thought to the little guys on the frontline – our immune system.
In a previous health article, we discussed how to boost our overall health as the threat of Corona looms, but taking care of our immune system, specifically, is worth turning our attention to.

The microbiome has been under the spotlight in recent years as scientists try to understand the full impact of it on our health, but what they do know is that it is intricately linked to our immune system. In fact, some authors state that as much as 75% of our immune system is housed in our gut. “Some have suggested that the immune system should be renamed to reflect its true role as what might be called a ‘microbe interaction system’”, states Justin Sonnenberg in his book, Gut Reaction.

Our bodies are hosts to a few microbiomes but for the purposes of this article, we will be discussing the gut microbiome.

Unbeknownst to many of us, there is a community of a hundred trillion microorganisms (belonging to over 2000 species and potentially containing 150 to 500-fold more genetic material than human DNA) that have taken up residence in our guts. They have evolved with us as a species, and if looked after well, have many health-promoting benefits, one of which is a vibrant and effective immune system.

Unfortunately, modern day lifestyle and the Standard American Diet (SAD) which many people have adopted, largely due to convenience and lack of time, does not support a healthy microbiome. According to David Perlmutter in his book, “The Grain Brain – Whole Life Plan”, an unhealthy intestinal microbiome can be caused by:

• diets high in refined carbohydrates, sugar and processed food
• diets low in fibre (especially the kind that feeds the microbes)
• dietary toxins such as gluten and processed vegetable oils
• chronic stress
• chronic infections
• the use of antibiotics and other medications such as nonsteroidal anti-inflammatory drugs and acid-reflux drugs like proton pump inhibitors.

Justin Sonnenberg adds meat and saturated fats to this list.

Boost your microbiome with plant based foods.

That said, how can we go about improving the state of our intestinal microbiome, and thereby fine-tuning our immune systems? Firstly, the diversity of gut flora is very important. We’re able to increase the numbers and, more importantly, the varieties of microbes by consuming a broad range of plant-based foods. Think vegetables, fruits, herbs, spices, legumes, pulses, nuts and seeds. Not only will some microbes be present on these foods from the soils they’re grown in (preferably organic) but all of these different foodstuffs feed different microbes, hence developing as many populations as possible.

For most individuals, fermented foods should be part of our diets as these are responsible for populating our guts with microbes. A good start would be a bowl of sugar-free yoghurt (by the way, artificial sweeteners are damaging to the gut flora and ultimately result in weight gain in most individuals.) Home-made is always better. From yoghurt to kefir (fermented milk) to water or coconut water kefir, to sauerkraut or other vegetable krauts. Kimchi (a spicy Korean dish made from fermented vegetables), tempeh (a fermented soy bean dish from Indonesia), miso (a Japanese paste made from fermented soy beans and rice, barley or seaweed), natto (another Japanese product made from fermented soy beans) and pickles. Unfortunately shop-bought pickles are stored in vinegar and are not made using the same fermentation process so these do not afford our bodies the probiotic benefit.

We also need to eat prebiotic foods such as dandelion greens, Jerusalem artichokes, garlic, onions, leeks, asparagus, artichokes, bananas, apples, konjac root (contains glucomannan), cocoa, burdock root, flax seeds, jicama root and seaweed. The fibres in these foods feed the microbes in our guts by fermenting them and forming Short Chain Fatty Acids (SCFA.) These, in turn, nourish the cells of the gut lining and assist in the amelioration of inflammatory responses to pathogens. One of the reported concerns with Covid-19 has been, in some patients, an over-reactive immune system resulting in the overproduction of mucus and inflammation, damaging the lungs and resulting in respiratory failure and death.

According to PubMed (see reference below), a large study performed on a cohort of 168,999 women and 219,123 men showed that, in both genders, dietary fibre intake was significantly linked to a 22% decrease in mortality rates from infectious, cardiovascular, and respiratory diseases.

So while time is available to you during this lockdown period, why not spend some time in your kitchen, preparing some of these dishes and give your immune system a little boost of nurturing.

Justin  and Erica Sonnenburg’s Bacteria-Boosting Granola

(6 grams of fiber per serving, not including added fruit)
Store-bought granola usually has an overabundance of added sugar, which is unfortunate because granola has great potential for supporting microbiota health. This recipe keeps all the great dietary fiber but eliminates much of the added sugar. To keep it interesting throughout the year, we often add seasonal fruit when we eat the granola.

• 4 cups mixed rolled cereal grain (or 1 cup each of flakes from oats, barley, rye, and quinoa; substitute as desired)
• 1 cup unsweetened dried flake coconut
• 1 cup chopped almonds
• ½ cup pumpkin seeds
• ½ cup pumpkin puree
• 3 tablespoons olive oil
• ½ cup water
• 2 tablespoons maple syrup
• 1 teaspoon ground cinnamon
• 1 teaspoon vanilla extract
• ½ cup raisins

INSTRUCTIONS: Preheat the oven to 180˚C. In a large bowl, mix together the rolled cereal, coconut, almonds, and pumpkin seeds. In a small bowl, whisk together the pumpkin puree, olive oil, water, maple syrup, cinnamon, and vanilla. Pour the wet mixture over the cereal mixture and stir to coat. Spread the mixture onto a large baking sheet and bake for 40 minutes or until golden brown, stirring halfway through. Add the raisins to the cooked granola. When cooled, store the granola in a covered container in the refrigerator. Granola keeps well for at least a month. Serve about ¾ cup over yogurt or kefir with seasonal fresh or thawed frozen fruit.

Angela Schaefer is a director of the Prue Leith Culinary Institute and a Functional Medicine Health Coach

Interested in Fermentation? Attend our short course to learn more. 

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