Resolving sleep issues can improve and even eradicate other health conditions. That’s how important sleep is for us! But can changing your diet improve how you sleep? Yes, it can! And it goes far beyond just not drinking coffee at night. Let’s take a look!
The Importance of Sleep
Sleep itself does not generate energy. The energy in our body comes from Adenosine Triphosphate (ATP), a molecule mainly derived from glucose, which powers everything we do. Sleep does not create ATP—so why do we have less energy when we don’t sleep?
Prolonged wakefulness disrupts the balance between ATP consumption and restoration because we use less energy when we sleep. Also, during sleep, mitochondrial function is restored. Mitochondria are the energy factories of our cells, where ATP is generated. When they don’t receive their nightly maintenance, they become less efficient at producing energy.
During Sleep, Our Brain Detoxifies
Although our overall energy use decreases during sleep, ATP production in the brain actually increases. This is because sleep plays a critical role in brain restoration.
In the brain, beta-amyloid plaques can build up, which are linked to Alzheimer’s and other neurodegenerative diseases. These plaques come from a larger protein called Amyloid Precursor Protein (APP), which is normally involved in cell growth and repair. When APP is broken down properly, it forms harmless protein fragments. However, sometimes beta-amyloid is produced instead, which is sticky and clumps together, forming plaques in the brain. These plaques disrupt communication between neurons and promote inflammation and oxidative stress.
During sleep, the glymphatic system (the brain’s lymphatic system) clears out these plaques, along with adenosine—a compound that builds up during the day and makes us feel groggy.
Sleep Supports Neuroplasticity
Sleep boosts BDNF (Brain-Derived Neurotrophic Factor), which supports synaptic growth and helps neurons form and strengthen connections. During sleep, the brain strengthens important neural pathways and prunes unnecessary ones. This consolidates memory, enhances learning, and supports habit formation.
Lower levels of BDNF make it harder for the brain to reorganize itself and adapt, which can negatively impact cognitive function.
The Link Between Sleep and Depression
There is a bidirectional relationship between sleep deprivation and depression1. Poor sleep alters the synthesis of key neurotransmitters like serotonin, dopamine, and noradrenaline, which help regulate mood. Chronic sleep loss can cause imbalances that greatly increase the risk of depression.
Additionally, prolonged sleep deprivation raises cortisol levels. High cortisol can increase brain inflammation, further disrupting neurotransmitter function and increasing the risk of depression.
Immune System Support
Sleep plays a vital role in maintaining a healthy immune system, including the regulation of T cells, which are crucial for adaptive immunity2.
During sleep, the body releases cytokines such as interleukin-12 and interferon-gamma, which are essential for T cell function. The decrease in cortisol during sleep is also beneficial—high cortisol levels can suppress immune function, making us more vulnerable to illness.
Metabolic Health
Sleep deprivation reduces insulin sensitivity, meaning cells don’t respond as effectively to insulin. This leads to higher blood sugar levels and increased insulin production, which, over time, can contribute to metabolic disorders like type 2 diabetes.
Additionally, poor sleep increases levels of ghrelin, the hunger hormone. This can explain sugar cravings after a bad night’s sleep3. More ghrelin, combined with reduced ATP production, makes us hungry and crave sugar for a quick energy boost.
At the same time, leptin—the hormone that signals fullness—is suppressed. This means you can eat more than you actually need. And if that wasn’t enough, sleep deprivation also weakens impulse control, making it harder to resist cravings.
In short, poor sleep can be a major trigger for overeating and weight gain.
Heart Health
Lack of sleep can increase blood pressure4 and influence the development of atrial fibrillation—an irregular and often rapid heart rhythm. This condition can lead to poor blood flow, increasing the risk of blood clots, stroke, heart failure, and other cardiovascular complications.
Fertility
Because sleep deprivation disrupts hormone regulation and the circadian rhythm, it can negatively affect fertility.
In men, testosterone levels drop, as testosterone is primarily produced during REM sleep. Its productions is also inhibited by higher cortisol levels.
For women more cortisol also generates hormone imbalances and additionally, poor sleep interferes with the communication between the hypothalamus and the pituitary gland, which is necessary for releasing FSH (follicle-stimulating hormone)5. FSH supports follicle development, and low levels can lead to irregular cycles and difficulty conceiving.
Improves Athletic Performance
During sleep, the body releases growth hormone, which stimulates muscle repair, regeneration, and growth. Sleep also enhances protein synthesis, which supports muscle recovery after exercise.
Additionally, sleep strengthens neural connections in the motor cortex, reinforcing newly learned movements and skills. Studies show that during sleep, the brain replays muscle activity, solidifying skills and improving coordination.
In short, sleep is essential for both muscle recovery and motor skill learning, making it crucial for athletes, exercisers, and anyone working on movement-based skills6.
3 Diet Tips for Better Sleep
Now that we know why sleep is so important, let’s look at some simple ways to improve it.
1. No Coffee After Noon
After noon? Yes. Caffeine takes about 12 hours to fully clear from your system. If you drink coffee at 3 PM, caffeine may still be in your body at 3 AM, affecting your sleep. In case you experience difficulty to fall asleep, you may want to quit coffee earlier in the day.
Cacao also contains stimulants, though less caffeine than coffee. Still, some people find that drinking hot cocoa at night affects their sleep.
Certain teas, like black and green tea, also contain caffeine and may not be the best choice before bed.
2. Less Carbs, More Fats and Protein
Waking up between 1 and 4 AM can have various causes. Alcohol makes us fall asleep easily, however wake us up at night. The same can happen with a disturbed liver, hormonal imbalances, or low blood sugar.
When our blood sugar levels fall too low, adrenaline will kick in to set all processes in motion to balance sugar levels again, and this wakes us up. When blood sugar falls too low (hypoglycemia), the body sees it as an emergency because the brain depends on glucose for energy. In response, the body activates the sympathetic nervous system, triggering the release of adrenaline from the adrenal glands. This signals the liver to convert stored glycogen into glucose so energy can be generated.
Keeping your blood sugar steady is thus important for a good night’s sleep. Therefore, skipping meals or eating high-sugar-content foods before sleep is not something I would advise you to do.
Generally, carbs and sugars are more quickly processed and used by our bodies. This means that after a high-carb meal, your blood glucose levels can go up quickly but also drop again in a short amount of time. To prevent your blood sugar from going too low during the night, it is best to eat foods that keep you nourished for a longer time. I like to eat some nuts in the evening, as they are rich in healthy fats. You can also opt for a dinner with a bit fewer carbs and a bit more protein.
3. Correct Meal Timing
Although a nutrient-dense dinner can improve sleep, eating too late can be counterproductive. Digestion should be finished before lying down to prevent stomach issues.
Eating at consistent times trains the body to release insulin in a predictable pattern, keeping blood sugar stable.
Cortisol should peak in the morning to wake us up and then drop in the evening when melatonin rises. Eating late at night can keep cortisol levels higher than they should be, disrupting sleep.
The liver, which plays a key role in nutrient processing and detoxification, functions best at night when we’re resting—not digesting. Late-night eating can interfere with this process, leading to inflammation and poor-quality sleep.
To support your natural rhythms:
- Don’t skip breakfast—it sets the tone for the day and aligns your internal clock.
- Eat meals at roughly the same time each day (within a 30-minute window).
- Finish dinner at least 2–3 hours before bed.
Meal timing, in a way, becomes the conductor of your body’s internal orchestra, harmonizing various biological rhythms.
Personalized Advice
These general tips can significantly improve sleep, but if you want to take it further and fine-tune your diet for optimal rest, energy, and balance, feel free to reach out! I’d love to help you create a diet that fully supports your needs so you can get the most out of life!
Pictures
Coffee: Bianca Gasparoto
Woman waking: Anna Nekrashevich
Neuroplasticity diagram taken from the review: “The Combined Influences of Exercise, Diet and Sleep on Neuroplasticity”
https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2022.831819/full