By Stephanie Eckelkamp
Food can be your best friend or worst enemy when it comes to managing a variety of health conditions. Just ask anyone who has reversed their type 2 diabetes by ditching the refined carbs or drastically reduced their rheumatoid arthritis symptoms after adopting an anti-inflammatory diet. Dietary habits and mood are clearly connected, too. This, of course, is clear in your day-to-day life whenever you experience that drop in energy and spike in irritability shortly after having a big slice of your co-worker's birthday cake.
But the connection between diet and mental health goes a lot deeper than getting a little hangry now and then. About five years ago, I learned this firsthand. After suffering increasingly severe symptoms from a mystery illness (which I'd later learn was Lyme disease) to the point that I could no longer walk more than five minutes without debilitating pain, I had to leave my job in NYC and move back in with my parents. I felt completely isolated and slipped into such a low emotional state that I'd wake up crying and walk (or hobble) through my days in an apathetic fog. But one day, on a whim, I decided to ditch my go-to breakfast cereal and PB&J sandwiches for a veggie-heavy, paleo-style diet to help ease my pain. After a month, my pain was still there, but something I never expected happened—I felt significantly more optimistic—dare I say happy? I'm certainly not alone in my experience either.
"These days it's common to hear food referred to as medicine. What's so surprising to many people is the fact that this statement powerfully applies to mood," says David Perlmutter, M.D., renowned neurologist and host of the upcoming series Alzheimer's: The Science of Prevention.
In fact, an emerging field of research known as nutritional psychiatry is getting an increasing amount of attention for just this reason, with studies revealing drastic improvements in depression, anxiety, and other conditions among patients who make strategic dietary changes. This has prompted more mental health professionals to start asking their patients a simple yet potentially life-altering question: What have you been eating?
The research on food as a mental health treatment is stronger than ever. The field of nutritional psychiatry emerged about 10 years ago, thanks in large part to researchers like Felice Jacka, whose 2010 Ph.D. study found that women whose diets were higher in vegetables, fruit, fish, and whole grains (with moderate red meat), were less likely to have depression or anxiety than women who consumed a diet high in refined carbohydrates, added sugars, and other processed foods. For a long time, there was this idea of the mind and body being separate, and there was a lot of skepticism when Jacka first proposed her Ph.D. study. But that has all changed. Now, Jacka is the director of the Food & Mood Centre at Deakin University in Australia and president of the International Society for Nutritional Psychiatry Research; and in the past few years, clear evidence has emerged suggesting that we can no longer look at mental health and brain health in isolation.
"We now have a very large and consistent evidence base...to say that the quality of your diet is linked to your risk of depression in particular," Jacka said in a recent video she posted to her Twitter page earlier this month. But while the observational evidence between diet and mental health has been clear for several years, only recently have randomized controlled trials shown that improving diet may actually help treat mental health conditions like depression.
Case in point: The 2017 SMILES study, led by Jacka, found that moderately to severely depressed people who were coached by a dietitian to follow a Mediterranean style diet for 12 weeks experienced significant improvements in mood compared to people who simply received social support. By the end of the study, around 30% of patients receiving the nutritional support were in remission for their depression compared to 8% of the social support group. Even more recently, a 2019 meta-analysis examined 16 randomized controlled trials looking into the impact of dietary interventions on mental health and concluded that improving diet (namely by increasing vegetables and fiber and scaling back on fast food and sugars) does have a measurable benefit to depression—and to a lesser extent, anxiety.
This exciting body of research—along with other research examining the effect of individual foods and nutrients on mental health—has prompted a number of mental health professionals to incorporate food into their practice in a big way (even some colleges, like Columbia University, are starting to teach psychiatry students about the food-mood connection).
In addition to the usual questions about mental health history, social support systems, and goals, Drew Ramsey, M.D., an assistant clinical professor of psychiatry at Columbia University and a self-proclaimed nutritional psychiatrist, asks patients to describe what they eat. He's looking for potential nutrient deficiencies/insufficiencies that may affect mental health and exacerbate symptoms as well as insight into a person's relationship with food. From there, he will guide patients on how to tweak their diet to support their overall mental health, often in conjunction with more conventional modalities like talk therapy and medication.
Other practitioners, like nutritional psychiatrist Georgia Ede, M.D., utilize lab work to evaluate metabolic health and nutritional status. "These include blood tests for insulin resistance (sometimes referred to as prediabetes or carbohydrate intolerance) and for nutrient deficiencies such as B12 and iron deficiency," she says.
Article continues belowWhat diet are psychiatrists prescribing to patients? There's not just one.Right now, most of the research has been done on a Mediterranean diet, with some research showing that people who eat this way (think: cutting out processed junk and loading up on fiber-rich veggies, fruits, fish, nuts, beans, legumes, olive oil, fermented foods, and some meat) have a 30 to 50% lower risk of depression. But many experts agree that there may not be one diet that's optimal for mental health. A number of dietary approaches, provided they include the right balance of brain-boosting nutrients (e.g., omega-3s, vitamin B12, zinc, iron, magnesium, and vitamin D) may do the trick.
To help his patients cover their nutritional bases, Ramsey guides them toward the nutrient-dense food groups that most Americans fall short in: leafy greens, brightly colored "rainbow" vegetables, seafood, and fermented foods. From there, he'll talk with patients about what food within those categories they might enjoy and how to prep and cook them in a simple, joyful way. As a useful tool, he and a colleague created an antidepressant food list, featuring the plant and animal foods (oysters, salmon, watercress, and spinach to name a few) that contain the highest levels of nutrients proven to help prevent or reduce depression.
Interestingly, while plant-based diets are often considered the holy grail, they may not actually be ideal for mental health. "There's some correlational data that people who eat no red meat, or who eat vegetarian diets, are at a much greater risk of depression," says Ramsey. "This isn't popular data among the plant-based crowd, but I think it's important to consider." But even so, Ramsey believes it's his job as a nutritional psychiatrist to help you "feed your brain" regardless of the particular diet you subscribe to—whether that's Whole30 or vegan. So, if you're passionate about consuming zero animal products, he'll provide support and make sure you're eating and supplementing in a way that supports mental wellness.
Other nutritional psychiatrists, like Ede, take a slightly different approach. While she says the most important food rule for mental health is to eat whole foods and avoid modern processed foods (namely refined carbohydrates and refined vegetable oils like soybean and corn oil), she often suggests that patients experiment with eliminating grains, legumes, and dairy as well.
"I generally recommend what I call a 'pre-agricultural whole foods diet' made up of whole plant and animal foods as one of the best ways to meet the brain's nutritional needs," she says. While nixing all grains and legumes may sound odd, she says these foods contain phytic acid, which can interfere with the absorption of important brain-healthy minerals like magnesium and zinc; and lectins, which can damage the gut lining and aggravate the immune system. This approach is enough for most people, but sometimes Ede will go a step further with patients. "For people who have insulin resistance, I recommend a lower-carbohydrate or perhaps even very low-carbohydrate ketogenic version of this same diet."
Several years ago, Ede met with a 40-year-old woman who'd had lifelong symptoms of procrastination, poor motivation, low energy, distractibility, and disorganization that interfered with her work and home life. She diagnosed her with ADHD and prescribed Adderall, which definitely helped but brought uneven benefits throughout the day and caused unpleasant side effects like constipation. She gradually removed grains, legumes, dairy, and most processed foods from her diet, which helped her mood and improved her physical health yet did nothing for her ADHD. But when she agreed to try a ketogenic diet this year, her symptoms began improving within a few days. "She has since stopped taking Adderall and reports that she functions even better when in ketosis than on Adderall, and without any side effects," says Ede.
The truth is, every body is a little bit different, and the fact that there are slightly different approaches within the nutritional psychiatry field is likely a really good sign.
So, how exactly does food affect the body to boost your mood? "Our food choices, both directly, as well as through influencing the activity of our gut bacteria, play a meaningful role in regulating our moods," says Perlmutter.
In fact, according to the experts I interviewed, there are likely three main mechanisms by which the diets described above promote mental wellness: by providing your brain with the nutrients it needs to grow and generate new connections, tamping down inflammation, and promoting gut health.
"Our brains continue to make new connections that give birth to new brain cells into our adult life, which is known as neuroplasticity, and the major regulator of this process is a neurohormone called brain-derived neurotrophic factor (BDNF)," says Ramsey. Low levels of BDNF have been associated with both depression and Alzheimer's, but certain nutrients such as zinc, magnesium, and the omega-3 fatty acid DHA promote the expression of BDNF.
Nixing refined carbohydrates, sugars, and highly processed vegetable oils can help significantly reduce inflammation as well. "Inflammation causes oxidative stress (a form of biochemical stress), which leads to distress signals in the brain that can lead to either depression or anxiety—or both," integrative physician Vincent Pedre, M.D., recently told mbg. "On the flip side, we know that the brain will release [pro-inflammatory] cytokines in response to mental stress."
This is why an anti-inflammatory diet, like the Mediterranean diet, which contains fatty fish such as salmon and sardines that are rich in omega-3s can be such a great choice. "DHA is powerfully anti-inflammatory and has been associated not only with reduced Alzheimer's risk but improvement of depression as well," says Perlmutter.
Finally, by forgoing processed foods and eating more fiber-rich foods (veggies, fruits, legumes, whole grains), prebiotic foods (onions, scallions, garlic, artichokes, leeks, cabbage) and probiotic foods (fermented foods like kimchi, sauerkraut, and kefir), the good bacteria in our gut are able to thrive, leading to an overall healthy microbiome. "Quite a bit of research shows that the microbiome really impacts our reaction to stress and anxiety," says Lisa Mosconi, Ph.D., a neuroscientist, nutritionist, and associate director of the Alzheimer's Prevention Clinic at Weill Cornell Medical College.
This is in part due to the gut's impact on GABA, the major inhibitory neurotransmitter that's been implicated in a multitude of health challenges including anxiety disorders, insomnia, and depression. When our microbiome is healthy and populated with good bacteria, we can better regulate GABA production and benefit from its calming, soothing properties, says Mosconi. Too much bad bacteria, on the other hand, can sort of hijack the GABA system and impair your ability to cope with stress.
Beyond these three mechanisms, diets rich in whole foods are generally just great for maintaining balanced blood sugar, which is key for staying calm, happy, and level-headed on a day-to-day basis.
Related ClassHow To Control AnxietyWITH ELLEN VORA, M.D.
So, can you rely solely on food as a form of mental health therapy?Sometimes dietary tweaks recommended by nutritional psychiatrists are enough to help a patient avoid or go off medication (as with Ede's patient above), but that's not necessarily the goal of nutritional psychiatry. The simple fact is psychiatric medication is a potentially life-saving tool that has its place. "A concern I have with the food as medicine movement is that it can lead to this idea that needing medication or other treatments somehow means that you're failing," says Ramsey. "But I rarely find food to be the only treatment I give a patient. I spend a lot of time with patients in psychotherapy, and I prescribe medications as responsibly and effectively as I can when they're indicated."
It's also important not to forget about other lifestyle factors that can make a huge difference in your mental health—and many nutritional psychiatrists and other functional medicine practitioners implement these tools in their practice as well. "These efforts must go well beyond food choices," says Perlmutter. "The flames of inflammation are fanned by stress, lack of exercise, and most importantly, not enough restorative sleep. Interestingly, each of these is independently associated with risk for both depression as well as Alzheimer's disease."
The future of nutritional psychiatry. The research makes it clear that we can no longer look at mental health in isolation—we must look at it as part of a whole complex system, which most definitely includes what we eat. Here at mbg, we are so excited to watch the body of nutritional psychology research grow, and we look forward to more mental health professionals making nutrition a cornerstone of their treatment. Encouragingly, the Omega Institute is offering its first-ever nutritional psychiatry training for health care professionals this fall, taught by Ramsey, which means more of this knowledge will soon get to the people who need it most. If you're personally interested in working with a nutritional psychiatrist or therapist and can't find one in your area, inquire about video visits—many practitioners will be happy to work with you virtually.
By Stephanie Eckelkamp
Scientists now have more evidence than ever before revealing the intimate, intertwined relationship between the mind and body. We see this with gut health's influence over our mental health, but we also see it with the very real physical manifestations of psychological stress and trauma on the body—tension, heart palpitations, trembling, pain—particularly trauma that hasn't been fully processed or even acknowledged by the person who experienced it.
Perhaps the most extreme example of how trauma may affect the body: According to research by Kelly Turner, Ph.D., terminally ill cancer patients who have experienced unexpected remission—beating their disease against all odds—often cite releasing emotional stress or trauma as one of the key factors in their healing.
This has led some people to speculate that unprocessed trauma gets "stored" not just in your subconscious mind and memory but throughout your physical being—and that, in addition to more traditional modalities like cognitive behavioral therapy, some sort of physical stimulus or touch may be helpful in releasing it.
But what do the experts think? Could this be why, for instance, some people start spontaneously crying during a massage or acupuncture session for no immediately apparent reason? It's an interesting idea, so we asked researchers, psychiatrists, and healers for their take on why something like this might occur, whether trauma can, in fact, be stored in the body, and the safest ways to go about releasing it.
First, you need to understand that trauma affects everyone at one point or another. As humans, we will all experience some sort of trauma. In fact, some estimates suggest 70% of adults in the United States have experienced some type of traumatic event at least once in their lives. And while trauma is a word we often associate with war, a violent attack, rape, abuse, or near-death experiences, the reality is there are a range of other less obvious experiences that can be traumatic and that have the potential to seriously disrupt our lives.
"Trauma is going to come to all of us sooner or later," says James S. Gordon, M.D., author of The Transformation: Discovering Wholeness and Healing After Trauma and founder of The Center for Mind-Body Medicine. "It's true that some experiences are most obviously traumatic, like rape or war, but things like dealing with a serious illness in yourself or a family member, the death of someone close, the breakup of a significant relationship, or even losing a job or leaving a community that's very important to you can be traumatic."
Trauma isn't something that has to be one specific event, either. "There's much more appreciation these days for micro-traumas—like chronic, more mildly traumatic things—that cumulatively over many years can amount to the same as one macro trauma," says Ellen Vora, M.D., holistic psychiatrist. You can think of these as big-T and little-T traumas.
The problem, of course, is that the negative psychological and physical effects of any type of trauma don't always resolve on their own, and may extend far beyond the actual event. Case in point: post-traumatic stress disorder (PTSD)—a mental illness that can develop after a person experiences or witnesses a terrifying or life-threatening event(s), including any of those mentioned above—which may last the remainder of someone's life if left untreated.
BY SARA ADÃES, PH.D. , SEPTEMBER 11, 2019
Key Learning Objectives
ENERGY HOMEOSTASIS AND HEALTHY WEIGHT
Energy homeostasis is the balance the body achieves from all the processes involved with the energy we take in (e.g., calories) and use. It is the result of a dynamic control of energy intake, via the regulation of appetite and satiety, and energy expenditure, via basal metabolism, heat generation, and physical activity. In a simplified sense, when we maintain energy homeostasis our weight stays about the same over time.
To maintain energy homeostasis, the brain needs to know when our energy reserves are low so it can tell us to feed; likewise, it needs to be informed of what and how much we ingest so it can tell us to stop eating. To be able to do so, the brain needs to receive input from other organs informing it of the body's energy state and energy reserves. The brain maintains homeostasis by integrating this neural and chemical input and adjusting our energy intake and expenditure accordingly.
The gastrointestinal (GI) tract is the major source of information about our energy intake. Thus, it plays a key role in the regulation of energy homeostasis. As we’ve seen in What is the Gut-Brain Axis?, the brain, the gut, and the microbiota are linked by a bidirectional neuronal, endocrine, and immune communication system known as the gut-brain axis.
In this article, we will take a look at the role of the gut microbiota and the gut-brain axis in metabolism and energy homeostasis. We will learn how food-derived chemical signals—nutrients and microbial metabolites—are translated in the gut into endocrine and neural signals that convey information about the caloric load and composition of a meal to the brain. We will also discuss the impact of diet on the gut microbiota and on the mechanisms of energy homeostasis, particularly the regulation of appetite.
Energy homeostasis is maintained through the dynamic control of energy intake and energy expenditure.
HOW ENTEROENDOCRINE CELLS SENSE THE GUT
Scattered throughout the lining of the GI wall, in contact with the gut lumen (i.e., the space inside the GI), a type of gut-specific endocrine cells called enteroendocrine cells (EECs) can be found. EECs are important because they have a sensory apparatus at their surface that allows them to sense the gut lumen. They sense gut nutrient levels—sugars, fats, and proteins—and microbial metabolites, and communicate those levels by producing signaling molecules called gut hormones or gut peptides.
EECs produce over 20 different gut peptides. Each gut peptide is released in response to specific stimuli (e.g., nutrient composition of a meal, caloric load of a meal) and collectively they act as a code that (1) signals what and how much we have eaten, and (2) triggers adequate metabolic and behavioral responses.[3,4]
Following their secretion, gut peptides can activate nearby neurons of the vagus nerve or the enteric nervous system (ENS), the gut’s own nervous system. Enteric and vagal neurons can sense nutrients directly, but because neuronal innervation does not extend to the gut lumen, direct nutrient sensing is restricted to absorbed nutrients and local metabolic products. The input from gut peptides is then sent to the brain via the vagus nerve. Gut peptides can also reach the systemic circulation and act directly on the brain. [1,3,5]
Chemical signals from nutrients and microbial metabolites are translated in the gut into neuroendocrine signals that convey information about the caloric load and composition of a meal to the brain.
HOW GUT PEPTIDES INFLUENCE ENERGY HOMEOSTASIS
Neuronal inputs from the gut are conveyed to energy regulation centers in the brain, where they are integrated with energy reserve signals (such as leptin and insulin, for example) and other hormonal and neurochemical inputs to regulate appetite and energy expenditure. Blood-borne gut peptides also stimulate satiety centers in the brain directly to decrease appetite.[2,4,6]
Gut peptides act locally as well. For example, they change gastrointestinal motility and secretion and increase gastric distension, which helps create that feeling of fullness that stops us from overeating. They also modulate insulin and leptin secretion to adjust glucose and fatty acid utilization.[3,4,6]
Appetite-inhibiting gut hormones also act by decreasing the secretion of appetite-promoting gut hormones, the most prominent of which is ghrelin—actually known as the hunger hormone. Ghrelin secretion, which occurs mostly in the stomach, is determined by absorbed nutrients and by neural and hormonal signals. Ghrelin secretion rises when the nutritional status is low to stimulate hunger and food intake; its levels fall rapidly after a meal in part due to the action of gut peptides.
Besides decreasing energy intake, gut-derived neuroendocrine signals within the gut-brain axis also influence energy expenditure.[1,6] Gut peptides can increase energy expenditure by increasing motor output, basal metabolic rate, and brown adipose tissue (BAT) thermogenesis (i.e., heat generation).[6,8]
In table 1, you can see a few examples of appetite-inhibiting gut peptides, what stimulates their secretion, and what their actions are.
Gut hormones signal the nutrient composition and caloric load of a meal and trigger physiological responses that modulate appetite and energy expenditure.
HOW THE GUT MICROBIOTA INFLUENCES ENERGY HOMEOSTASIS
We have a mutually beneficial symbiotic relationship with the gut microbiota. This means we cooperate and help each other. We help bacteria by feeding them what we eat. In return, they help us digest and extract energy from food, transforming nutrients we wouldn’t be able to absorb into other forms that can be taken up by the gut into the blood.
Metabolites produced by the gut microbiota include short-chain fatty acids (SCFAs), secondary bile acids, choline metabolites, phenolic compounds, indole derivatives, vitamins, neurotransmitters and neurotransmitter precursors, and bioactive lipids. Through these metabolites, the gut microbiota can influence the activity of EECs, gut hormone secretion, appetite, and energy storage.[9,10] Many of these microbial metabolites are essential for our health.
Short-chain fatty acids (SCFAs), which include the molecules acetate, propionate, and butyrate, are particularly relevant in the crosstalk between microbial and human metabolism. SCFAs are mostly produced from the breakdown of nondigestible fibers and starches and they account for up to 10% of human energy requirements. The SCFA butyrate is the primary energy source for epithelial cells in the colon, propionate is used by the liver to produce glucose, and acetate is transported in the blood to other tissues were it can be oxidized and used as a substrate for energy metabolism.[1,11,12]
But beyond being a source of energy, SCFAs are also signaling molecules. SCFAs bind to receptors expressed by EECs, influence nutrient-sensing, and regulate gut hormone secretion.[1,6,9] SCFA receptors are also expressed in neurons of the vagus nerve and ENS and in immune cells.[13,14] Thus, SCFAs can regulate and have a significant impact on the gut-brain axis, and consequently, on appetite, food intake, metabolism, and energy homeostasis.[15–17]
SCFAs also act on liver and muscle cells, where they regulate glucose utilization and energy expenditure, and on adipose cells, where they regulate fat storage.[13,14] SCFAs can also regulate energy homeostasis by stimulating leptin production in fat cells. Leptin is a hormone produced by adipose tissue that signals the state of fat stores to the brain and inhibits hunger.
Secondary bile acids are another type of microbial metabolite that also act as signaling molecules. Secondary bile acids result from the degradation by gut microbes of a fraction (5 to 10%) of bile acids (or bile salts) produced in the liver from cholesterol and secreted in bile. [Bile acids are molecules that facilitate the metabolism of dietary fat and the absorption of fat-soluble vitamins and cholesterol.] Microbiota-derived secondary bile acids influence signaling pathways involved in energy and lipid metabolism, production of fatty acids, and triglyceride storage.
Microbial metabolites influence nutrient-sensing, the production of gut hormones, and the gut-brain axis. Thus, the gut microbiota influences energy intake and energy storage in our body.
HOW DYSBIOSIS AFFECTS WEIGHT GAIN
The composition and diversity of the gut microbiota, which determines the levels of SCFAs and secondary bile acids, for example, is known to be one of the factors that influence our feeding behaviors and appetite.[19,20] In turn, the composition and diversity of the gut microbiota is determined by the diet.
Overnutrition and high-sugar and high-fat diets can have a particularly negative impact on the gut, creating imbalances in microbial composition and diversity, referred to as dysbiosis. Unhealthy diet-induced dysbiosis can have a significant impact on energy homeostasis: it can alter microbial signaling, gut nutrient-sensing, gut peptide sensitivity, and endocrine, immune, and neuronal signaling to the brain.[21,22] These dysfunctions in the gut-brain axis will result in abnormal appetite control, leading to further overeating.[1,6,23]
The composition and diversity of the gut microbiota is one of the factors that determines appetite and feeding behaviors.Animal studies have given us a glimpse of the extent of the metabolic impact of the gut microbiota. For example, colonization of germ-free mice with a gut microbiota from obese mice was shown to induce more weight gain than with a microbiota from lean mice. This increased weight gain was attributed to the composition of the gut microbiota of obese mice. It was shown that obese mice have a microbiome (the genetic pool of the microbiota) enriched in genes involved in the extraction of calories from indigestible carbohydrates and in the stimulation of fat production and fat accumulation, for example.
It’s likely that a similar process occurs in humans. Because of differences in the composition of the gut microbiota induced by unhealthy diets, overweight individuals may become more effective at extracting energy from food and at storing and accumulating fat.
Furthermore, one of the immediate consequences of overeating or high-fat and/or high-carbohydrate diets is the excessive production of some gut peptides. If this behavior becomes customary, tolerance to gut peptides develops over time and their satiety-promoting effect consequently decreases. This creates a crescendo of overeating and tolerance that, along with dysbiosis, can lead to significant weight gain.
Diet-induced changes in gut microbiota composition and diversity contribute to the dysregulation of energy homeostasis associated with excessive weight gain.
HOW DIET MAY IMPACT METABOLIC HEALTH
Excessive weight and fat accumulation are often associated with a number of parameters that are indicative of generalized poor health, including insulin resistance, atherosclerosis, and other cardiometabolic dysfunctions.
The gut microbiota may play a key part in this process of health impoverishment.[26,27] For example, high-fat diets favor the growth of a type of bacteria that produce an endotoxin called lipopolysaccharide (LPS), a proinflammatory molecule. A chronic high-fat diet may increase plasma LPS concentrations two- to threefold. This type of diet-induced change in the gut microbiota can lead to gut barrier dysfunction (known as leaky gut). As a consequence, microbial products, such as LPS or other inflammatory molecules, may reach the blood and activate proinflammatory processes throughout the body, particularly in white adipose tissue.[29–31]
This state of generalized chronic low-grade inflammation induced by changes in the microbiota is known as metabolic endotoxemia. Gut dysbiosis and changes in intestinal barrier permeability have been implicated in what is known as cardiometabolic syndrome, a combination of symptoms associated with chronic low-grade inflammation—hypertension, insulin resistance, impaired glucose tolerance, dyslipidemia (high fat content in the blood), and abdominal adiposity—that can have massive detrimental effects on health.[32–34]
Changes in gut microbiota composition can lead to a state of chronic low-grade inflammation that contributes to poor cardiometabolic health.
HOW THE GUT MICROBIOTA MAY SUPPORT METABOLIC HEALTH
The gut microbiota can influence gut nutrient sensing and gut peptide release. Thus, gut microbiota manipulation is a potential tool to target the gut–brain axis and influence energy homeostasis to support metabolic health.
Raising the levels of SCFAs by, for example, increasing the dietary intake of indigestible starches and fibers is known to confer metabolic benefits. In animals with genetic obesity, dietary supplementation with SCFAs was shown to decrease weight gain, improve insulin sensitivity and increase energy expenditure. The metabolic benefit of chronic SCFA administration was associated with activation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and increased mitochondrial function, indicating that it can influence cell nutrient sensing and metabolic pathways.[17,36]
The composition of the gut microbiota can be altered using probiotics and prebiotics. Probiotics are “live microorganisms, which when consumed in adequate amounts, confer a health effect on the host.” A prebiotic is a “nondigestible compound that, through its metabolization by microorganisms in the gut, modulates composition and/or activity of the gut microbiota, thus conferring a beneficial physiological effect on the host.” Studies using probiotics and prebiotics have shown that these products are able to modify the gut microbiota in such a way that improves gut nutrient-sensing mechanisms and reduces food intake.
Also in animal studies, it was shown that probiotics increase the levels of satiety hormones, causing a reduction in food intake that suppresses body weight gain and improves metabolic parameters such as insulin sensitivity.[39–41] Similarly, studies in mice fed high-fat diets showed that prebiotics decreased food intake, weight gain, fat mass, and insulin resistance. [39,42,43]
In humans, probiotic administration has also been shown to support weight loss, an effect that was associated with reductions in circulating leptin levels. Likewise, prebiotic administration was shown to increase satiety and reduce hunger and the desire to eat, an effect most likely due to an increased release of satiety-signaling gut hormones.[45,46] In overweight adults, prebiotics induced weight loss and improved glucose regulation.
Probiotics and prebiotics modulate the composition and diversity of the gut microbiota and can be used to support metabolic health.
As our knowledge about the influence of the gut microbiota on our metabolism expands, it becomes increasingly clearer that a healthy diet supports a healthy gut microbiota, and that both are key factors in maintaining a healthy metabolic function. Likewise, it is becoming clearer that interventions designed to support a healthy gut microbiota may be highly beneficial in supporting a healthy metabolism and cardiometabolic function.
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BY BEN COTE , SEPTEMBER 24, 2019
You have less than a hundred days until the end of the year. Or maybe less, depending on when you are reading this. Of course it’s all arbitrary. The end of the year or the beginning of the next is just a day like any other. But as the time passes and we see and set dates for our goals and dreams, we are reminded of the work we want to do and the world we wish to create for ourselves.
What are your goals for the next 100 days?
Did you accomplish your goals you set in the last 100 days? Did you set any? Or are you just busy all the time? Is is not enough to be busy… The question is: what are we busy about? Henry David Thoreau
The influx of technology and our modern lifestyle have all but eliminated seasons or rhythms in our life. As we head into fall, it just feels like summer is getting started and as kids head back to school it can often feel like we just shift from one season of busy into another, almost indistinguishable from the last.
We struggle to keep up with work, bills and life in general as we do not carve out time to take care of ourselves or pause the busy, even if just for a moment, to not only appreciate the present but to think about the future we want to create for ourselves in the next season of our lives.
So you have less than 100 days. How does that make you feel?
Overwhelmed and already behind? Or energized and excited to take on your next goal?
You get to choose. The time will pass either way.
If you are in the overwhelmed camp, here is where you get to pause and take control.
Today can be day 1 for you if you want it to be.
M.Om., Dipl. Acu (NCCAOM) L.Ac.
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