Lack of sleep is a silent enemy undermining us every day. Our grandparents used to say: Get some rest, and things will get better. And although they said it more for love problems or toothaches, today it is increasingly clear that they were also right about diseases we didn't used to call civilization-related.

In the modern world, the average person sleeps between 6 and 6.5 hours per night, while experts recommend at least 7 to 9 hours of quality sleep. In the US, where they have the highest rates of obesity and diabetes in the world, more than a third of adults sleep less than 6 hours per night. In Europe, the data is similar: at least 30% of people sleep too little, and among young adults, the number is even higher.

Why is this important? Because sleep is not just rest, but part of the body's regulation. Just like water regulates our temperature, sleep regulates our hormones, appetite, metabolism, and even the desire to move.

What happens when we don't sleep enough?

When we are awake, the body is constantly functioning – metabolizing, producing hormones, regulating blood sugar. And if we don't get enough sleep, errors start to occur. One of the most crucial errors is called insulin resistance.

This means that our cells become "deaf" to insulin – the hormone produced by the pancreas that helps sugar move from the blood into the cells, where the body uses it for energy. When cells no longer respond correctly, sugar remains in the blood. The body then produces even more insulin until the pancreas is exhausted, leading to the development of diabetes.

This sounds serious – and it is. One study observed 28 young, healthy people aged 18 to 23. When they didn't sleep for 24 hours, they began to show signs of insulin resistance, even though they were otherwise completely healthy. In less than a day, the body started showing signs that lead to diabetes.

Hormones – the silent power of the body

When talking about blood sugar and body weight, we cannot ignore hormones. They are small chemical messengers that control appetite, energy expenditure, stress, sleep, and much more.

Lack of sleep causes an increase in cortisol – the stress hormone. Cortisol isn't bad by itself – it helps us get up in the morning and gather ourselves – but if there is too much of it, it raises blood pressure, increases appetite (especially for sweets), and eventually leads to fat accumulation in the abdomen, one of the most dangerous forms of obesity.

But the story doesn't end there. There are two more hormones that are extremely important for appetite control: leptin and ghrelin.

Leptin is produced by our fat tissue and signals to the brain: "I'm full." When we have enough leptin, the body doesn't need more food. On the other hand, ghrelin, produced by the stomach, causes hunger.

And now imagine this: after one sleepless night, leptin levels drop, while ghrelin increases. The result? Not only are you tired, but you are also hungry – and not for salad, but for bread, pasta, chocolate, and chips.

This was also confirmed by a study from 2004, which showed that people consume an average of 385 more calories after a sleepless night than usual. If this continues for weeks or months, the pounds quickly start to accumulate.

Exercise? Harder when we are tired

Again, we can rely on an old saying: A tired horse pulls poorly. If we are sleep-deprived, we lack the motivation to exercise. Instead of a walk or workout, we choose the couch, chocolate, or fast food.

Studies show that lack of sleep reduces energy expenditure. Not just because we move less, but also because the body uses quite a bit of energy during sleep – especially in the so-called REM phase. The REM phase is the one where we dream and dominates the second half of the night's sleep. If we only sleep 5 or 6 hours, we hardly reach this phase.

Interestingly, during this phase, the brain "resets," and the body burns more calories than at any other time during the night. If this phase is missed, metabolism decreases.

Why do mothers struggle to lose weight after childbirth?

Many young mothers wonder why they can't lose the weight gained after childbirth, even though they breastfeed and often don't have time for hearty meals. The answer, again, lies in sleep.

In the first few months after childbirth, mothers sleep very little and very intermittently. Their sleep cycle is disturbed, leptin hormone drops, ghrelin increases, metabolism slows down, and cortisol remains elevated most of the time. This is not the ideal combination for weight loss.

What does science say?

Over 60 scientific studies published in prestigious journals such as The Lancet, Sleep, and JAMA Internal Medicine have confirmed a direct link between lack of sleep and a higher risk of diabetes and obesity.

In 2015, one of the largest studies conducted in the US with over 100,000 adults showed that those who regularly sleep less than 6 hours per night have a 45% higher risk of developing type 2 diabetes and a 55% higher risk of obesity.

The WHO (World Health Organization) included sleep deprivation in 2019 among the top ten health risks of modern society.

How can you help yourself?

First: start taking sleep seriously. It's not a luxury but a basic need, just like water and food.

Second: create an evening routine. Keep the hour before bedtime screen-free. Try a cup of chamomile or lavender tea at least half an hour before bed – these natural remedies calm the nervous system.

Third: make sleep a priority, just like work or meals. Your body will thank you. And let it be clear – sleep is not a waste of time. It is the cheapest and most natural medicine we have.

In conclusion...

In simple terms: eating organic vegetables, going to the gym, and taking dietary supplements won't help if you only sleep 5 hours a night. The body simply needs sleep to do its magic. And although we are not doctors, we can listen to the body and nature – and nature says: Go to sleep!