According to microbiologist and researcher Kiran Krishnan and autoimmune expert Dr Datis Kharrazian, variety is not just the spice of life, a variety of vegetables is the answer to a long and healthy life because they nourish our microbiome, which in turn supports our immune system.

When we hear “microbiome”, the digestive and respiratory systems come to mind, but the microbiome is the sum of the genetic material of all the microbes: bacteria, fungi, protozoa and viruses, which live on and inside the human body. The microbiome and the immune system are different components of the same human ecological system. Microbiome bacteria help digest food, regulate the immune system, protect against pathogenic microbes, and produce beneficial substances like vitamins B12, thiamin, riboflavin, and vitamin K.

The microbiome acts as the eyes and ears of the immune system and, like a referee, provides signals to the immune system so that it knows when to react and when not to react. Krishnan asks you to imagine a stadium (the microbiome) with only one guardian (immune cell) for 200,000 spectators (beneficial microbes). The keeper relies on spectators to be on the lookout for trouble and to inform him. A greater number and variety of microbial bystanders informing immune guardian cells means the immune system can respond faster and better to protect the body by only targeting specific troublemakers before they spiral out of control.

Krishnan estimates that about 80% of the American population suffers from gut dysbiosis (an imbalance of microbes and leaky gut) which often leads to chronic diseases like diabetes, heart disease, hypertension, obesity and autoimmunity. A compromised respiratory and digestive microbiome, with low or small amounts of beneficial microbes to alert immune cells, gives bad actors (pathogens like influenza and COVID) more time to thrive. Bystander microbes signal so slowly that by the time the immune guardian cells respond, their response is very damaging not only to the pathogens, but to all of our cells (think blast furnace or nuclear bomb), and can result in a serious illness or death.

The immune system is one of the only parts of the body that constantly adapts to its environment, inside and out.

“As your environment changes, your immune function, your immune abilities, your restrictions, your actions, all of that changes,” Krishnan says.

To safeguard and improve your microbiome Krishnan advises six strategies:

• Eat more diverse vegetables and fruits. A diversity of plant-based foods nurtures a wider and more diverse range of beneficial microbes and supports their increase.
• Fast at least once a day for 12 hours. Digestion consists of three stages which take about 12 hours; some beneficial microbes proliferate only during these stages.
• Go out every day. When possible, open windows and doors. The air carries beneficial microbes to the respiratory and digestive systems, so take a deep breath of clean outdoor air.
• Manage stressors. Invite peace. Stress releases hormones like cortisol that signal bad organisms to act and release toxins.
• Get a pet. Pets increase microbial diversity. (And pets comfort and entertain us.)
• Play in the dirt. A Finnish study found that daycare children who played in dirt and forest developed healthier, more diverse microbiomes and increased killer T cells.

Dr. Datis Kharrazian believes that gut health is the foundation of our body’s health. Our diet has an impact on digestion, the quality of our intestinal microbes and the strength of our immune system. In his “3D Immune Tolerance Program,” Kharrazian offers an easy way to diversify our intake of vegetables, prebiotics, and fruits to increase the growth and variety of beneficial gut microbes.

Dr. Kharrazian’s Microbiome Mashup (a plant-based probiotic)

Finely chop at least 21 different types of organic produce (small amounts will do…they add up quickly), mix and freeze. You don’t need to eat a lot, maybe a teaspoon a day to start and work up to 3 or 4 tablespoons. Alternatively, chop the vegetables and puree them in a blender or food processor. Place 3-4 tablespoon-sized portions in a silicone mini muffin pan or on a parchment-lined baking sheet and freeze. Place the frozen vegetable patties in a freezer bag.

Mix one a day into a serving of smoothie, soup, hot water, stir fry, sauté, braise, warm salad, roast or stew.

When product choices are plentiful, prepare two different collections and alternate them.

You can use any organic vegetable, even frozen. I like to lightly steam sweet potatoes and quick kale in boiling water to increase digestibility, but it’s not necessary. Beware of adding fruit; keep it minimal and low glycemic, like a bit of apple or pear or a few red grapes. Add celery, fennel, radish, beet and turnip greens, broccoli, cauliflower, Swiss chard, kale and cabbage stalks.

You can add fiber (a “prebiotic” that feeds beneficial bacteria) such as ground psyllium, ground flax seeds, hemp seeds, chia seeds, seaweed, konjac shirataki noodles, garlic, Jerusalem artichokes, jicama, dandelion greens, onion family, broccoli, brussels sprouts or asparagus.

Nancy Krcek Allen has been a chef-educator for over 25 years and has taught professional and recreational courses in California, New York and Michigan. His culinary manual is called “Discovering Global Cuisines”.