How Your Sleep Cycle Impacts Your Health

We’ve all been there—staying out too late with friends or binge-watching our favourite series, only to feel the consequences the next day. How well we function throughout the day is directly influenced by our sleep. But what many don’t realise is how much our sleep cycle—the regularity and structure of our sleep phases—affects our overall health. A balanced sleep cycle is key to having more energy, maintaining a healthy metabolism, and boosting memory function. Discover how your sleep cycle works and how to optimise it for better health and well-being.

Table of Contents

What Is the Sleep Cycle?

The sleep cycle is better known to most of us as our "internal clock." Scientifically, it's referred to as the circadian rhythm—a natural pattern of sleep and wake phases. Don’t underestimate the importance of these cycles on your health. Like a healthy diet, quality sleep with an optimal rhythm can significantly enhance your well-being. Those who sleep well tend to be healthier, more energetic, and better able to achieve their goals, whether in sport or daily life.

Sleep isn’t a luxury; it’s a necessity. While we sleep, our body operates on a low power mode, triggering essential processes that aid in our recovery. Repair mechanisms kick in, and our metabolism is optimised. This regenerative period is crucial for maintaining good health. Like nutrition, sleep is one of the most powerful tools for supporting overall wellness.

A Healthy Sleep Cycle: How It Impacts Energy and Well-being

Sleep has numerous health benefits. It helps us stay mentally sharp, emotionally balanced, and boosts our immune system. It’s no wonder we tend to feel irritable and sensitive when we don’t sleep enough. Sleep influences a wide range of functions, including our attention span, reaction times, and even problem-solving abilities. Additionally, sleep is essential for forming memories.

If you’re active, regularly exercising, or trying to manage your weight, your sleep cycle plays an important role. A consistent sleep schedule helps regulate metabolism and can aid in weight management. Lack of proper sleep can increase the risk of weight gain. And crucially, sleep and fitness are intertwined. Research shows that muscle mass decreases more rapidly in those who get less than 5.5 hours of sleep per night.

Sleep Cycle Disrupted? Here’s How to Get Back on Track

With a bit of patience and the right approach, you can restore your body to a natural sleep cycle. Follow these tips:

  • Optimise your sleep environment: Your room should be dark and quiet. If necessary, try using a sleep mask and noise-cancelling earplugs to create the ideal conditions.
  • Rethink napping: If you’re struggling to establish a natural sleep cycle, consider shortening or eliminating daytime naps. Long naps during the day can prevent you from sleeping properly at night.
  • Regulate room temperature: Keep your bedroom cool—ideally between 16 and 20°C.
  • Improve your diet: Healthy foods are crucial for quality sleep. Avoid heavy meals before bed, and for better sleep quality, steer clear of caffeine, alcohol, sugar, and other stimulants.

Best Sleep Cycle: Tips for Restful Nights

Some simple habits can make a big difference in improving your sleep and finding a better rhythm. One key tip is to go to bed and wake up at the same time every day, including weekends. Consistency is vital. Regular physical activity also promotes better sleep, but avoid exercising intensely right before bed, as it can have a stimulating effect.

Diet is also important. Melatonin regulates our sleep-wake cycle and is produced from serotonin. You can boost serotonin levels in your brain through a diet rich in complex carbohydrates, such as fruit, vegetables, and whole grains.

These nutrients have a positive impact on sleep:

Magnesium

Promotes muscle relaxation and supports GABA production, a neurotransmitter that regulates the sleep cycle.
Sources: Nuts, seeds, leafy greens (e.g., spinach), whole grains.

Vitamin D

Regulates the sleep-wake cycle by influencing melatonin production. Deficiency can lead to sleep problems.
Sources: Fatty fish (e.g., salmon), eggs, fortified dairy, sunlight.

Vitamin B6

Plays a key role in serotonin production, which aids relaxation and converts into the sleep hormone melatonin.
Sources: Poultry, fish, bananas, chickpeas, potatoes.

Tryptophan

An essential amino acid that serves as a precursor to serotonin and melatonin, promoting relaxation and improving sleep quality.
Sources: Turkey, eggs, nuts, seeds, bananas, dairy.

Melatonin

The sleep hormone that regulates the body’s internal clock, signalling it’s time to sleep.
Sources: Cherries (especially tart cherries), tomatoes, walnuts.

Omega-3 Fatty Acids

Boosts melatonin and serotonin production, supporting brain health and promoting better sleep.
Sources: Fatty fish (e.g., salmon, mackerel), flaxseeds, chia seeds, walnuts.

Calcium

Helps convert tryptophan into melatonin and supports muscle relaxation.
Sources: Dairy, broccoli, almonds, kale.

Zinc

Supports the regulation of the sleep-wake cycle and helps calm the body for restful sleep.
Sources: Beef, pumpkin seeds, chickpeas, nuts.

Iron

A deficiency in iron can cause sleep disorders such as insomnia or restless leg syndrome, which affect sleep quality.
Sources: Red meat, spinach, lentils, quinoa.

Potassium

Regulates blood pressure and relaxes muscles, contributing to a more restful sleep.
Sources: Bananas, avocados, sweet potatoes, beans.

The 90-Minute Sleep Cycle: What You Need to Know

Curious about the 90-minute sleep cycle? The 90 minutes refer to the average length of a complete sleep cycle. Our sleep consists of several phases, which are divided into different cycles. A healthy adult goes through four to six of these cycles per night, each lasting between 90 and 120 minutes. First, we enter light sleep, followed by deep sleep. The body's regeneration processes occur during the deep sleep phase, making it particularly important for our health. As the night progresses, deep sleep phases gradually decrease, while light sleep phases increase.

At a Glance

  • 01.

    The sleep cycle, also known as the circadian rhythm, regulates the natural shift between sleep and wakefulness. A consistent, restful sleep enhances mental and physical performance, supports metabolism, and aids memory and emotional stability.

  • 02.

    A disrupted sleep cycle can increase the risk of weight gain, reduce muscle mass, and hinder the body's recovery processes. Improving sleep environments, diet, and daily routines can help restore a healthy sleep rhythm.

  • 03.

    Sleep occurs in cycles lasting about 90 minutes, alternating between light, deep, and REM sleep phases. Deep sleep is crucial for regeneration and overall well-being, especially in the earlier cycles of the night.

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↡ Survey of 527 AG1 customers after 12+ days of use, 2024. Vitamins C, B6, B12, riboflavin, niacin, pantothenic acid, and folate help reduce tiredness and fatigue. Pantothenic acid supports mental performance. Calcium supports normal digestive enzyme function, while biotin maintains normal mucous membranes, such as the gut lining.

Immune System

1: Copper, folate, selenium, zinc, and vitamins A, B12, B6, and C contribute to the normal function of the immune system. Vitamin C contributes to the normal function of the immune system during and after intensive physical activity. The positive effect is achieved if 200 mg of vitamin C are taken daily in addition to the recommended daily dose (80 mg). This is the case when taking AG1.

Metabolism

2: Vitamins C, B6 and B12, as well as thiamine, riboflavin, niacin, biotin, pantothenic acid, calcium, phosphorus, copper, and manganese contribute to normal energy-yielding metabolism. Biotin, zinc, and chromium contribute to normal macronutrient metabolism. Vitamin A and riboflavin contribute to normal metabolism of iron. Zinc contributes to normal acid-base metabolism.

Healthy Cells

3: Vitamins E and C, as well as riboflavin, zinc, copper, manganese and selenium, contribute to the protection of cells from oxidative stress. Zinc contributes to normal DNA synthesis. Phosphorus contributes to normal function of cell membranes.

Mental Performance; Mental Focus; Nervous System; Psychological Function

4: Vitamins C, B6, B12, riboflavin, niacin, pantothenic acid and folic acid contribute to the reduction of tiredness and fatigue. Pantothenic acid contributes to normal mental performance. Zinc contributes to normal cognitive function. Vitamins C, B6, B12, thiamine, riboflavin, niacin, biotin, and copper contribute to normal functioning of the nervous system. Thiamine, niacin, vitamin B6, vitamin B12, biotin, folate, and vitamin C in AG1 contribute to normal psychological function.

Healthy bones

5: Calcium contributes to the maintenance of normal bones. Protein, phosphorus, zinc, and manganese contribute to the maintenance of normal bones. Vitamin C contributes to normal collagen formation for the normal function of bones.

Cardiovascular System

6: Thiamine contributes to the normal function of the heart. Vitamins B6 and B12 contribute to normal red blood cell formation. Vitamin C contributes to normal collagen formation for the normal function of blood vessels.

Skin, hair, nails

7: Vitamin A, riboflavin, niacin, biotin and zinc contribute to the maintenance of normal skin. Vitamin C contributes to normal collagen formation for the normal function of skin. Biotin, zinc and selenium contribute to the maintenance of normal hair. Copper contributes to normal skin and hair pigmentation and to normal connective tissue. Selenium and zinc contribute to the maintenance of normal nails.

Hormonal Health

8: Vitamin B6 contributes to the regulation of hormonal activity. Pantothenic acid contributes to normal synthesis and metabolism of steroid hormones, vitamin D, and some neurotransmitters. Zinc contributes to the maintenance of normal testosterone levels in the blood. Selenium contributes to normal thyroid function and normal spermatogenesis. Zinc contributes to normal fertility and normal reproduction. Chromium contributes to the maintenance of normal blood glucose levels.

Digestion

9: Calcium contributes to the normal function of digestive enzymes. Biotin contributes to the maintenance of normal mucous membranes (e.g., intestinal mucosa).

Muscles

10: Calcium contributes to normal muscle function. Proteins contribute to the maintenance of muscle mass and an increase in muscle mass.

Healthy eyes

11: Vitamin A, riboflavin and zinc contribute to the maintenance of normal vision.

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