Why Can’t I Sleep at Night Even When I’m Tired?

You probably know that drinking coffee and alcohol can interrupt a good night’s sleep. But are you aware that snacking, overeating sugar, and not getting enough sun can stop you from sleeping at night?

Simple diet changes can fine-tune your sleep-wake cycle and reduce sleep problems by replenishing electrolytes and naturally boosting melatonin.

Let’s look at common reasons for poor sleep and learn how to promote healthy sleep habits by making beneficial dietary and lifestyle changes. 

Seven reasons why you can’t sleep when you’re tired 

Your sleep-wake cycle is controlled by sleep-regulating hormones, neuronal processes, and external cues such as light exposure and body temperature.

Research published in Nutrients found that certain dietary and lifestyle choices can cause hormonal imbalances and overstimulate the nervous system. This can cause difficulty falling asleep even when you are tired.¹

Here are seven reasons why you may not get enough quality sleep.

1. Frequent snacking

Snacking close to bedtime can significantly disrupt your internal body clock and lead to sleep issues. 

Digesting food requires energy and promotes metabolic activity, which can make relaxing and falling asleep challenging. 

2. High-carb diet 

Eating sugars and carbs can quickly raise blood sugar levels and trigger the release of insulin. This critical hormone regulates energy metabolism and fat storage.

Chronically elevated insulin due to a high-carb diet can lead to insulin resistance, a metabolic disorder characterized by a lack of cellular response to insulin signaling. Insulin resistance is linked to a frequent need to urinate, which can significantly impact sleep quality. 

In addition, insulin resistance is linked to increased systemic inflammation, which can worsen inflammatory sleep conditions such as obstructive sleep apnea.

3. Overeating protein

Consuming too much protein can trigger sleep issues in some sensitive individuals. 

Protein-rich foods, especially those containing high levels of the amino acid tyrosine, have been found to increase the production of the neurotransmitters dopamine and norepinephrine.

These neurotransmitters have excitatory properties and activate the nervous system, making it more difficult to wind down and fall asleep.

4. Alcohol 

Alcohol can make you feel drowsy and may help you fall asleep faster. However, alcohol significantly disrupts sleep cycles and causes fragmented sleep, leaving you tired and drained the next day.

Even small amounts of alcohol can suppress rapid eye movement (REM) sleep, which is vital for cognitive functioning, cellular repair, and recovery. REM sleep deprivation can lead to daytime sleepiness, impaired memory, and lack of focus.

A study published in the Handbook of Clinical Neurology summarizes, “Alcohol initially acts as a sedative. In the second half of the night, sleep is disrupted, with increased wakefulness followed by a period of poor quality sleep that can lead to a downward spiral, with insomnia being self-treated with alcohol to produce a rapid sleep onset.”²

5. Caffeine 

While moderate amounts of caffeinated beverages such as black coffee and tea have several health benefits, drinking too much can quickly impact your ability to fall asleep and stay asleep. 

Caffeine has been found to bind adenosine receptors in the brain. Adenosine is a calming neurotransmitter that promotes relaxation and sleep. 

By blocking these receptors, caffeine inhibits the sleep-inducing effects of adenosine and, due to its stimulating properties, promotes wakefulness at the same time. 

Caffeine is also a diuretic that can cause increased urination at night, potentially disrupting deep sleep phases, which can result in an inability to fall back asleep. 

6. Vitamin D deficiency

Vitamin D deficiency is widespread and can worsen sleep disorders such as sleep apnea. Maintaining optimal vitamin D levels may enhance sleep quality. 

Vitamin D, the sunshine vitamin, has potent anti-inflammatory properties and promotes normal immune functions. 

Low vitamin D levels are linked to chronic inflammation and may contribute to the narrowing of the upper airway, which increases the risk of obstructive sleep apnea.

7. Stress

Stress activates the body’s fight-or-flight response and triggers the release of stress hormones such as cortisol and adrenaline. 

These hormones activate metabolic processes and increase pulse rate and blood pressure, which can cause difficulties falling asleep and explain why stress can significantly disturb sleep quality. 

Interestingly, research published in the Journal of Clinical Trials found that just one night of partial sleep deprivation increases average cortisol levels the following day, perpetuating the vicious cycle of elevated cortisol and poor sleep quality.³

Watch the video below to learn which foods to avoid if you want a good night’s sleep. 

Circadian rhythm explained

The circadian rhythm, also known as your internal body clock, regulates the neuronal, metabolic, hormonal, and mental changes your body undergoes within a 24-hour cycle. 

Circadian rhythms are mainly influenced by light and darkness and controlled by the suprachiasmatic nucleus (SCN). This small region of the brain receives nerve signals about light and dark from specialized cells in the retina of the eyes.

The SCN is like a biological clock that controls the production of melatonin, a crucial sleep hormone that prepares your body for sleep.

Melatonin levels increase during the evening and decrease in response to bright light in the morning, which triggers wakefulness. 

Poor sleep hygiene habits–such as exposure to blue light emitted from digital screens, inconsistent sleep patterns, and an uncomfortable bedroom–can impact melatonin production and sleep cycle regulation, which increases the risk of restless nights and sleep disorders.        

Tips for falling asleep faster at night

Getting enough restful and rejuvenating sleep is crucial for physical and mental well-being. During sleep, your body recovers, consolidates memories, and restores energy. 

Sleep issues can make you sick and significantly increase the risk of various health conditions, including obesity, diabetes, heart disease, and weakened immune defenses. 

Here are four tips on how you can fall asleep faster at night.

1. Avoid too many fluids during the evening

Drinking too many fluids close to bedtime may cause you to wake up due to a full bladder. 

Reducing your water intake during the evening hours can help you avoid having a constant urge to pee at nighttime. 

2. Increase zinc-rich foods

Zinc has unexpected sleep benefits, and increasing zinc-rich foods such as oysters, seafood, and red meat can support your sleep health.

Zinc is needed for the production of melatonin and enhances its sleep-promoting properties. This essential mineral has also been found to support the function of GABA (gamma-aminobutyric acid), a crucial neurotransmitter that facilitates a calm and relaxed state conducive to sleep.

3. Boost melatonin naturally 

Boosting melatonin levels naturally can help you fall asleep faster, stay asleep longer, and support a healthy, balanced sleep-wake cycle for better overall rest and recovery.

Here are several steps you can take to boost melatonin levels naturally:

• Keep a consistent sleep schedule 
• Reduce blue light exposure from digital screens during the evening 
• Avoid bright lights and dim surrounding lights two hours before bedtime 
• Avoid snacking and alcohol close to bedtime
• Combine a ketogenic diet with intermittent fasting 
• Keep your bedroom dark and cool 

4. Find ways to relax 

Calming an overactive nervous system is crucial to prepare the body for restful sleep, and using relaxation techniques throughout the day can help mitigate stress, anxiety, and racing thoughts. 

Exercise and stress-reducing activities such as stretching, breathing exercises, or taking a warm bath before bedtime can help you wind down and relax. 

Why you’re tired during the day

Daytime sleepiness is often linked to delayed sleep phase syndrome (DSPS), a sleep disturbance characterized by an inability to fall asleep at a conventional bedtime. 

Most people with DSPS feel tired but can’t sleep and often don’t get enough restorative sleep, causing tiredness and lethargy during the day.

If you suffer from sleeping problems, you may have considered sleeping pills or other sleep medicine, which typically contain sedative compounds. However, most sleeping aids don’t work and often interfere with regular sleep cycles, making you more tired.

Sedatives are metabolized in the liver, and depending on the exact type and dosage of sleeping aids, your liver may not entirely eliminate these compounds overnight, and you may continue to experience sedative effects the following day.  

What causes insomnia on keto?

Insomnia can occur for various reasons when following a ketogenic diet. While most people notice improved sleep when doing keto, others may experience disrupted sleep patterns.

Here are four potential reasons to experience sleep issues when following keto. 

1. Increased energy 

Keto typically increases energy levels due to the metabolic changes triggered by burning fat as the primary fuel source. 

While more energy is one of the many health benefits of a low-carb diet, it can cause temporary sleep issues. Having more energy may mean your body feels less tired during the evening, which can cause difficulties falling asleep or waking up too early.

Increasing physical activity typically resolves this issue and helps get a good night’s rest.  

2. Inadequate intake of calcium and magnesium  

If you are doing keto but aren’t focusing on a nutritious low-carb diet like Healthy Keto® that provides ample nutrients while maintaining ketosis, you may be at risk of mineral deficiencies.

Magnesium and calcium are essential in relaxing muscle tone and calming the nervous system, and deficiency can increase the risk of DSPS and insomnia.

Consuming plenty of mineral-rich green leafy vegetables, full-fat dairy, and seeds and nuts promotes a relaxed body and may help you get restful sleep.

3. Lack of potassium-rich foods 

“Replenishing potassium is crucial to support healthy sleep when doing keto,” explains Dr. Berg.

Keto, especially during the early phases of keto-adaptation, can trigger increased urination and depletion of essential electrolytes.

Potassium is the most important electrolyte for sleep regulation. Lack of adequate potassium can cause an elevated pulse rate and increased blood pressure, resulting in an overstimulated nervous system, which can cause trouble sleeping.

To support optimal potassium levels, aim to include 7 to 10 cups of leafy greens and non-starchy vegetables in your daily diet, as they’re rich natural sources of this essential mineral. 

You can also make your own electrolyte drink with potassium, which is an excellent strategy to promote optimal electrolyte balance and support restful sleep. 

4. Vitamin B1 deficiency

If you started keto and often find yourself lying awake at night due to racing thoughts, you may have developed a vitamin B1 deficiency.

Vitamin B1 is involved in the production of neurotransmitters and hormones that influence sleep and wakefulness and helps promote a calm nervous system, which is essential for restful sleep.

Some of the best vitamin B1 sources include sunflower seeds, pork, salmon, tuna, asparagus, spinach, and pasture-raised eggs. 

Watch the video below to learn what causes insomnia on keto.

When to seek a sleep specialist

It’s best to consult a sleep specialist if you suffer from persistent sleep issues that affect your daily functioning and quality of life.

If you experience any of these sleep problems, it’s recommended to consult a sleep expert:

• Chronic insomnia
• Excessive daytime sleepiness
• Restless legs syndrome at night
• Sleep apnea
• Shift work-related sleep disorders
• Night terrors  

A sleep study typically includes a comprehensive evaluation and diagnostic tests to formulate personalized treatment plans tailored to your specific needs.

FAQ

Sources

1. https://pmc.ncbi.nlm.nih.gov/articles/PMC7230229/ ?
2. https://pmc.ncbi.nlm.nih.gov/articles/PMC5821259/ ?
3. https://pubmed.ncbi.nlm.nih.gov/9415946/ ?