What Are Nervine Herbs?
Nervine herbs – ranging from skullcap to oats, linden, lemon balm, chamomile, and rose, to name a few – rebalance internal tension helping to support a calm, even response to the stresses and challenges of everyday life. While they are gentle and mild in their actions – certainly not full-on sedatives – this is actually an advantage. You don’t see dependence develop, and they can be used throughout the day as well to help keep stress and occasional anxiety at bay without making us feel sleepy at work. You can see how they make an excellent complement to the adaptogens: by decreasing our perception of stress, nervines spare the adrenal response from being invoked for every little annoyance that crosses our path. Save the stress response for what really counts! And with adaptogens on board, make sure that, even when that response occurs, it’s not overdone and recovery can happen well. One plant – tulsi, or holy basil – is one of my favorites because its rich aromatic profile has a pronounced nervine effect, while its less volatile chemistry has well-documented adaptogenic action. It’s the best of both worlds – which is probably why tulsi is so revered in the Ayurvedic medical system.
Our two adrenal glands are located on top of each kidney. From this perch, they not only have access to a rich blood supply but are also close to the site of fluid and mineral balance in the body. This makes sense given their role: they participate in the stress response, of course, but are also involved in energy, libido, lean muscle growth, immune response, blood pressure, blood sugar, and water balance. So you can see how the hormones secreted by our adrenal glands have far-ranging effects: from the short-acting jolt of adrenaline to the longer-term influence of cortisol, which modulates metabolism in the liver, reduces our sensitivity to insulin, and suppresses inflammation (and immunity). We think of the adrenal glands as producing stress hormones, and this is true – but while we can perceive the effects of acute stress (heart racing, clammy hands, perhaps some anxiety), it is the more subtle ongoing hormonal activity of the adrenals that ends up having more profound effects on energy, metabolism, sleep, and mood. Unfortunately, this is hard to see until it’s gone: when our adrenal function begins to drop off, we notice fatigue, lack of motivation, metabolic slowdown, sleep disruptions, and more pain.
It is this last piece that usually serves as a good indicator that our adrenal function is sub-optimal: if we recover more slowly from vigorous exercise, feeling more fatigue – and crucially, more pain – after a big hike, or an extra-long jog, it can often mean that our reserve of adrenal hormones is flagging. This ability to recover and feel ready again is a key piece of the adrenal response, and, as it turns out, to healthy sleep patterns, too. When our adrenal health is solid, hormone secretion rises in the pre-dawn hours, helping to boost our energy and mood and reduce symptoms of inflammation, right before we wake up. As a result, we wake feeling ready to go! But as adrenal health deteriorates, affecting our ability to recover, we wake feeling more sluggish, noticing more pain. This is because adrenal hormone levels haven’t had a chance to build up to good levels overnight. During the day, as we experience stress, they try to catch up – and often do – but by now it’s late evening and time to go to sleep. The higher evening hormone levels make it hard to get to sleep, and our crucial recovery time is disrupted – further depleting adrenal reserves. It’s the classic “wired and tired” picture, where hormone secretion has shifted from high-AM and low-PM to low-AM and high-PM.
Adrenal hormone secretion is controlled by a few different organs. The kidneys themselves trigger the release of hormones that balance fluid and sodium levels. The nervous system, in response to the daily sleep/wake rhythm and to environmental stressors, regulates the secretion of hormones like cortisol, DHEA, and adrenaline. If we are to support adrenal health, we often work with herbs that affect water balance in the kidneys and the perception of stress in the nervous system, because this “upstream” strategy takes the burden off the adrenal glands and allows them to replenish their reserves of hormones. When addressing adrenal health as part of having good energy, healthy sleep patterns, and a balanced stress response, we turn to herbal adaptogens and nervines.
Adaptogens have broad-ranging effects, but this is mostly because they affect adrenal hormone secretion. In general, we can think of adaptogenic herbs this way: they set an “upper limit” on the signals the nervous system can send to the adrenals, making it harder for the body to crank adrenal response up to 100%. Some herbs, like licorice, keep adrenal hormones in the bloodstream longer: this lets the brain know that there’s plenty of response happening, and it doesn’t need to stimulate more. Others, like Rhodiola and eleuthero, help balance out excessive adrenal stimulation while at the same time containing chemistry that supports the activity of attention- and alertness-enhancing brain pathways. The net result: we feel more alert, but at the same time don’t produce excessive, unhealthy levels of adrenal hormones. Contrast this to the action of stimulant drugs (like amphetamines, or even caffeine): they increase brain alertness, but also crank up adrenal secretions. This is why stimulants make us feel awake, but also sometimes jittery, cold, and clammy: these last effects are the result of excess adrenal hormone secretion, and you’ll never feel them from adaptogens like Rhodiola or eleuthero.
Other adaptogens are more calming in nature: they still help set an “upper limit” on adrenal hormone secretion, but also encourage deeper, more refreshing sleep and lack any of the activity on alertness pathways in the brain. By supporting more effective recovery during times of rest, adaptogens such as ashwagandha and Schisandra allow the body to bounce back and we can really notice this during the day: a balanced mood, energy level, and inflammatory response. It’s interesting to note that these herbs won’t ever make you “sleepy” directly: their effects, due in part to limiting the body’s ability to “overdo” the stress response and make sure our adrenals secrete hormones at balanced, healthy levels, are to get us into a more restful place during the evening and nighttime hours, so recovery and sleep can actually take place.
When you put it all together, using adaptogens and nervines to help support healthy energy, mood, libido, and inflammatory response become fairly intuitive. First, learn to recognize the signs of shifting adrenal hormones: feeling unrefreshed in the morning and “wired but tired” in the evening; noticing more inflammation and longer recovery times after vigorous workouts; relying more on stimulants during the day and sedatives at night. Next, develop a relationship to more alertness-enhancing adaptogens, like Rhodiola and eleuthero, during the morning hours. I often recommend one dose on waking, and another right before lunch. This will help support good adrenal activity when you need it most, while also making sure that the adrenals don’t overdo it. Additionally, especially if sleep patterns are being affected, consider some more calming, restorative adaptogens, like ashwagandha or tulsi, in the afternoon and evening hours. Finally, have a good nervine formula on hand to try during the day, especially if you feel a lot of tension and irritability. Their gently supportive, soothing actions will insulate the adrenals from the stress of the little things in life. But if you support excellent adrenal health, you’ll find yourself turning to these nervines less and less: a great sign that tonic herbalism has worked its magic yet again.