It is a well-known fact that a good night’s sleep, besides exercising and a healthy diet, is essential for our mental and physical wellbeing. But what is perhaps unknown to many is that poor sleep can significantly increase the risk of several lifestyle diseases such as obesity, high blood pressure, diabetes, and heart diseases. These diseases may result in decreased life expectancy. On the other hand, getting enough and quality sleep can improve your brain function, boost your immune system to fight infections better, maintain hormonal balance in the body, and aid in the healthy growth and development in children.
Lifestyle diseases associated with poor sleep
Research shows that people who sleep for less than 6 hours on an average have a higher Body Mass Index (BMI), while those getting sleep of 8 hours per night have the lowest BMI. People with a BMI of 30 and above fall in the ‘obese’ category. Lack of sleep not only causes obesity in adults but also in children. Short or poor-quality sleep increases the risk of obesity by de-regulating the appetite leading to higher calorie consumption. During sleep, the brain signals the body to secrete hormones that help control appetite, regulate glucose processing, and energy metabolism.
Inadequate sleep creates an imbalance in these hormones that include:
- Increased production of cortisol (stress hormone)
- Increased secretion of insulin which regulates glucose metabolism and promotes fat storage
- Lowered levels of another hormone known as leptin that helps regulate energy balance by inhibiting hunger and reducing the fat storage
- Higher secretion of ghrelin, a hunger-stimulating hormone which increases food cravings.
- Heart diseases
Studies have revealed that short or poor sleep quality is associated with several cardiovascular diseases, including coronary heart disease, stroke, and irregular heartbeat. The factors that link reduced sleep to heart diseases include:
- Hypertension - High blood pressure is one of the leading risk factors for heart disease and stroke. While blood pressure reduces during normal sleep, inadequate sleep keeps the blood pressure high for a longer duration. Over time, insufficient sleep makes the body lose its ability to regulate stress hormones leading to high blood pressure.
- Higher levels of inflammation - Inflammation is a well-known risk factor for heart disease and stroke. A protein called CRP (C-reactive protein) that is released during stress and inflammation is elevated in sleep-deprived individuals.
- A higher heart rate is observed in sleep-deprived individuals, which indicates heightened stress that affects heart health.
- People with sleep disorders such as obstructive sleep apnea wake up several times each night as it affects the ability to breathe during sleep. It happens due to an obstruction in the airways and affects the amount of oxygen circulated when one is asleep. This is related to an increased risk of high blood pressure, heart attack, and stroke.
- Insomnia, a condition in which individuals have trouble falling asleep or staying asleep, is linked to high blood pressure, a major risk factor for heart diseases.
Studies suggest that a single night of inadequate sleep in people with existing hypertension can raise their blood pressure throughout the following day. From this, the association of poor sleep with the development of heart diseases can be established.
Studies have reported that lack of sleep increases insulin resistance, the body’s inability to use insulin, leading to type 2 diabetes. Sleep influences glucose metabolism, the process of breakdown of sugars for use as energy. Research indicates that people who slept for 4 hours every night have impaired glucose metabolism than those who slept more. Factors contributing to type 2 diabetes that are linked to lack of sleep include:
- When a person goes into a deep sleep, the activity of the nervous system goes down, and the brain needs less glucose. Also, there is an increase in the production of growth hormones and a decrease in the stress hormone. Inadequate sleep impairs glucose regulation in the body and increases stress hormone.
- Lack of sleep may also increase cravings for high-fat and high-sugar foods that lead to diabetes over time.
- Poor sleepers also tend to consume more calories later in the day. This disrupts the circadian rhythm, the internal process which regulates the sleep cycle, leading to weight gain and impaired levels of insulin and blood glucose.
- In people with sleep apnea, lack of oxygen causes stress which induces the release of glucose into the bloodstream. Over time, the individual can develop insulin resistance resulting in type 2 diabetes.
Tips to sleep better
Now that we understand the importance of sleep, let us look at some tips on how to sleep better to keep lifestyle diseases at bay:
- Try going to sleep at the same time every day and follow the same for waking up. Ensure that this routine is maintained on all the days including weekends.
- Consume light meals instead of heavy ones before bedtime. Avoid consumption of alcohol before going to bed.
- Refrain from using electronic devices with bright artificial light such as mobile phones, TVs, and laptops before bedtime.
- Substances such as caffeine (found in tea, coffee) and nicotine (found in cigarettes) can interfere with your sleep. Hence, it is best to avoid these substances before your sleep time.
- Regular physical activity can help you sleep better. However, strenuous exercise should be avoided at least a couple of hours before bedtime.
Getting enough sleep each night should be one’s priority for a healthier, productive, and happier life. Doctors recommend 7 to 8 hours of sleep per night for adults for optimal health. Sleep experts also warn that sleeping for more than 9 hours may do more harm than good. However, sleep needs may vary from person to person and change throughout life. If you wish to know how much sleep your body needs to keep you away from diseases, speak to our team of experts.