Insomnia’s Five Subtypes: Here’s How to Address Each One

Sleepless nights can be more than just an occasional inconvenience—they often come with exhaustion, frustration, and confusion about why nothing seems to help. If you’ve (or your patients have) tried different remedies but still struggle to get quality rest, understanding the specific nature of insomnia is the key to unlocking deeper, restorative sleep. In this article, you’ll find a link to an in-depth guide by my friend and colleague, Dr. Damiana Corca, on how to understand the different subtypes of insomnia, allowing you to personalize your approach to achieve better sleep results. I also encourage you to check out her book, The Deep Blue Sleep. 

 

Sleep changes with aging, but it doesn’t just change with aging; it can also start to explain aging itself – Matthew Walker, Sleep and Neuroimaging Laboratory, University of California, Berkeley

Sleep Deprivation, Health and Aging

Bottom line – we do much worse with poor sleep. Research tells us that chronic lack of sleep can significantly increase the risk of various diseases, including cardiovascular issues, diabetes, obesity, and neurodegenerative conditions like Alzheimer’s disease. Sleep is critical for the body’s repair mechanisms, which operate during the deeper stages of rest. When sleep is consistently disrupted, or we don’t achieve restorative deep sleep, these repair processes are impaired, leading to systemic inflammation and a weakened immune response. Post-exercise muscle recovery can even be compromised by poor sleep. Furthermore, poor sleep exacerbates oxidative stress, a key contributor to cellular aging and disease progression.

Sleep deprivation also influences epigenetic regulation, altering the way genes are expressed without changing the underlying DNA sequence. For instance, inadequate sleep can modify gene activity linked to stress responses, metabolic pathways, and inflammation. Over time, these changes can accelerate biological aging and increase susceptibility to chronic illnesses such as those mentioned above. This connection between sleep and aging is so fundamental that, as UC Berkeley’s Matthew Walker notes, “Sleep changes with aging, but it doesn’t just change with aging; it can also start to explain aging itself.” I can’t underscore enough how important sleep is, and how much can be improved when we reverse poor sleep.

The Five Types of Insomnia

As we know well in functional medicine, there can be many individual variations of many diseases, meaning that one person’s insomnia can have different underlying biochemistry than the next person’s. Clearly, the term “insomnia” alone does not capture the complex patterns of sleeplessness we might experience.

My friend and colleague Dr. Damiana Corca offers a smart alternative, drawing from her years of clinical practice and insights (and shared in her book The Deep Blue Sleep). She identifies unique insomnia types based on root causes and contributing factors (i.e., the classic functional medicine “antecedents, triggers, and mediators”), offering a more effective path to healing.

Here are the five main types of insomnia and how they manifest:

1. The Anxious Type This form of insomnia, as the name suggests, is often fueled by anxiety. For some, this manifests as difficulty falling asleep, while for others, it’s characterized by early morning awakenings. Common experiences include lying awake for hours due to overwhelming worry or waking up at 2-4 a.m. feeling restless and unable to return to deep sleep.

Antecedents and triggers for this type often include emotional stress, past trauma, or significant life transitions. For women, hormonal changes during perimenopause can also amplify anxiety and disrupt sleep patterns.

2. The Overthinking Type This type is marked by a racing mind that won’t switch off, often accompanied by digestive issues or blood sugar fluctuations. People with this type may struggle to fall asleep as their thoughts spiral, or they might wake up around midnight to 2 a.m., unable to quiet their mind.

Physiological contributors include poor gut health, hormonal imbalances, and even stress-induced neurotransmitter depletion.

3. The Overtaxed Type This insomnia type is tied to the modern fast-paced lifestyle, where juggling responsibilities leads to burnout. People with overtaxed insomnia often wake up earlier than intended, around 2-3 a.m., feeling wide awake but physically drained.

Chronic stress, irregular schedules, excessive screen time, and unprocessed emotional burdens often underlie this type. Physical stressors like inflammation or undiagnosed health issues can also play a role.

4. The Depleted Type Most commonly affecting individuals in their 40s and beyond, this type of insomnia manifests as waking up after 4-5 hours of sleep and finding it impossible to return to rest. Unlike other types, the person often feels calm yet resigned to being awake.

Over time, neurotransmitter levels like serotonin and GABA decline due to chronic stress, aging, or poor diet, contributing to this form of insomnia. Additional factors include genetics, cumulative damage from infections or toxins, gut imbalances, and hormonal depletion.

5. The Overburdened Type This type is characterized by restless sleep and feelings of internal irritation or unease. People often wake up unsure how much rest they’ve had, feeling as though something is disrupting their system.

Root causes can include chronic infections (like Lyme disease), environmental toxins (such as mold or chemicals in personal care products), heavy metals, or gut health imbalances. Sleep apnea can also contribute to this type of insomnia, making it crucial to address the physical and environmental irritants preventing restful sleep.

The Importance of Understanding Your Insomnia Type

Each insomnia type reflects a deeper story about the interplay of stress, lifestyle, and physiological factors that impact sleep. Understanding your specific type can help guide you toward effective solutions rather than relying on one-size-fits-all remedies.

For example, addressing the anxious type may involve calming the nervous system through meditation and hormonal support. For overthinking insomnia, improving gut health and balancing blood sugar can have profound effects. Meanwhile, the overtaxed type often benefits from stress management and lifestyle adjustments, while the depleted and overburdened types may require comprehensive healing of the body’s systems with the support of a holistic practitioner.

Restorative sleep is possible, but it requires understanding your or your patient’s unique challenges and addressing them through a functional medicine lens. To learn more about each type of insomnia and discover tailored strategies for overcoming them, download the full guide.

Dr. Fitzgerald’s Recommended Sleep Support Supplements