‘Them” (1954), “Tarantula” (1955), “The Deadly Mantis” (1957) and, of course, “The Fly” (1958) are classic horror movies that make it clear just what humans think of creepy-crawlies. But many “bugs” are downright essential for good health and a long life — and they colonize your mouth and guts, as well as your skin and lungs. Your mission, should you decide to accept it, is to nurture and protect the 10,000 species that occupy your ecosystem, so they can do their jobs, which include everything from balancing your blood sugar to maintaining a happy disposition.

So we’re going to take a brief tour of some of your biomes to let you in on simple ways to make friends with your ride-along microbes.

DIGESTIVE TRACT BIOMES

Say ahh! The oral biome is the gateway to your body. While some of the microbes stay on your tongue or soft palate and in biofilms coating the teeth and gums, others are just passing through on their way to your guts and lungs. Tooth decay, gingivitis and periodontal disease all can increase oral bacteria that contribute to diabetes, inflammatory bowel disease, anxiety, depression, Alzheimer’s disease, heart disease and even premature birth.

But healthy teeth and gums can protect your oral biome and your health by strengthening your immune system, reducing inflammation and aiding your digestion. Your smart steps:

1. Ditch mouthwash. Brush and floss twice a day; scrape or brush your tongue, too.

2. Eat a plant-centered diet. Eliminate all added sugars and syrups.

3. If you suffer from dry mouth or mouth breathe while sleeping, that can harm the healthy balance of bacteria in your mouth. Ask your dentist about what can help keep your mouth shut while you’re asleep and saliva substitutes and other techniques to increase moisture.

GUT INSTINCTS

Research shows that 45% of the bacteria found in your mouth show up in the gut as part of the 100 trillion bacteria, both good and bad, that live there. When your gut biome is in balance, it ups your resistance to infection and chronic inflammatory diseases, including inflammatory bowel disease and diabetes, some cancers, autoimmune diseases and allergies, obesity and mental illness. Your smart steps:

1. Exercise daily: This includes 10,000 steps plus 30 minutes of aerobics and two 20-minute strength-building sessions weekly. Exercise increases gut microbes that produce a fatty acid called butyrate, which in turn helps produce satiety hormones that curb hunger, and protects and promotes new growth of brain neurons. Exercise can also improve your health by causing gut chemistry changes that force more direct contact between gut microbes and immune system cells.

2. Eat food that nourishes beneficial gut microbes. High-fiber veggies and fruits and 100% whole grains and legumes will do the trick. Prebiotics like low-fat yogurt and sauerkraut feed the good bugs. Avoid red meat. Studies show that animal protein can increase microbes that are associated with inflammatory bowel disease and increase production of TMAO, a compound that promotes cardiovascular disease. Also, ditch added sugars and ultraprocessed foods.

3. Ask your doc about taking a probiotic daily.

LUNG AND SKIN BIOMES

>> Breathe: Your lung microbiome is composed of aspirated oral bacteria and microbes from the air. If you’re a smoker, are exposed to toxic pollutants, or if unhealthy oral microbes invade your lungs, you become susceptible to COPD, allergies, asthma and more. Smart moves: Never smoke anything, and make sure you have good oral health.

>> Smooth: The skin microbiome can ward off skin disease and irritation, and prevent infection from entering the body. However, modern hygiene using antibacterial products, frequent showering and application of everything from wrinkle creams to deodorant and sunscreen damages the biome mix. Smart moves: Avoid antibacterial personal care products; when you shower, use soap where needed but don’t lather up every square inch. Use only micronized zinc oxide for sunscreen, and rely on hats and SPF clothing for primary protection.

Mehmet Oz, M.D., is host of “The Dr. Oz Show,” and Mike Roizen, M.D., is chief wellness officer and chairman of the Wellness Institute at Cleveland Clinic. Email questions to youdocsdaily@sharecare.com.