Many of my patients are shocked to learn that their microbiome, this microscopic community that lives on and in them, plays such a vital role in their health and well-being, including their weight, their mental state, and their moods.

If you, too, are wondering how these invisible creatures can affect you so deeply, consider that our bodies did not evolve independently.  Rather, we co-evolved with the bacteria that were on this planet long before we got here. As a result of this joint evolution, there are many functions that we cannot perform on our own.  Even our ape ancestors depended on the microbiome, and we humans certainly do. From our very first moments as homo sapiens, our bodies have relied upon its community of bacteria not just to remain healthy, but to survive at all.

Consider one of the microbiome’s primary tasks: enabling us to digest our food and  metabolize nutrients. Isn’t it remarkable to think that without the trillions of bacteria that live within us, we couldn’t absorb the nutrients we consume?  And that when that bacterial community is out of balance, we don’t absorb enough nutrients.

Another key job of our microbiome is to maintain a healthy gut by nourishing the cells of the gut wall. This wall is only one cell thick and most of your immune system is just on the other side.  So it, too, relies upon the microbiome to function at its peak. When your microbiome is out of balance, your immune system struggles, and you’re likely to suffer from frequent colds, allergies, joint pains, acne, and, potentially, more serious disorders.

We need the microbiome to keep our gut healthy because the gut is so vital to our overall health. Besides its role in digestion, it also helps us process thought and emotion—so much so that it is often referred to as “the second brain.”  To take just one example, 70 percent of your serotonin—a feel-good chemical that promotes emotional well-being, self-confidence, and good sleep—is made in the gut. When your microbiome is in good shape, chances are, your gut is too—and your serotonin and other neurochemical levels are more likely to be optimal.  As a result, you feel calm, balanced, optimistic, and confident, and you are likely to sleep well.

But when your microbiome is out of balance, your gut suffers.  As a result, your production of serotonin and other neurotransmitters drops, leaving you vulnerable to depression, anxiety, self-doubt, and sleep problems.  We think of these issues as “brain problems,” but in fact, the biochemicals that govern them are more densely populated in the gut. So really, they could be “gut problems.

Every day, we are learning more about how the microbiome and the gut affect our emotions and our brain.  In fact, while I was writing my book 10 Reasons You Feel Old and Get Fat, a study revealed that the microbes within us literally evolved to affect our food choices!  By releasing signaling molecules into our gut, the bacteria in our bodies can actually engineer our cravings.  

One of the researchers, Athena Atkipis of the Arizona State Department of Psychology, explains: “Microbes have the capacity to manipulate behavior and mood through altering the neural signals in the vagus nerve, changing taste receptors, producing toxins to make us feel bad, and releasing chemical rewards to make us feel good.”  Gut bacteria have such a huge influence on our thoughts, feelings, and mood that some people even call them “mind-altering micro-organisms.”

Your Microbiome and Your Brain

Healthy MicrobiomeUnhealthy MicrobiomeCalmnessAnxietyOptimismDiscouragementSelf-esteemSelf-doubtBalanceDepressionClear thinkingBrain fogSharp memoryMemory issuesHealthy sleepTrouble falling or staying asleepCraving veggies and other healthy choicesCraving sweets, starches, unhealthy fats

How an Imbalanced Microbiome Affects So Many Aspects of Your Health

• Brain:  anxiety, depression, brain fog, sleep issues, memory problems
• Digestive system: gas, bloating, indigestion, constipation, loose stools, heartburn, sugar cravings.
• Hormones: menstrual and premenstrual issues,  symptoms of perimenopause and menopause (hot flashes, skin problems, sleep difficulties, mood swings)
• Immune system:  frequent colds and flu, difficulty recovering from illness,  allergies
• Skin:  acne,  acne rosacea,  dermatitis, eczema, psoriasis
• Overall function:  fatigue, sleep difficulties, muscle pain, joint pain, weight gain,

So, as you can see, your microbiome helps protect your brain, your gut, and your metabolism.  When antibiotics or some other factor throws it out of balance, your brain and gut health suffer, your metabolism slows down, and your whole body becomes inflamed.  This inflammation produces weight gain as well as many other symptoms, including the gas, bloating, reflux, acne, and hormonal issues that bring so many patients to my door.

This is an adapted excerpt from my book, 10 Reasons You Feel Old and Get Fat… And How YOU Can Stay Young, Slim, and Happy!