Sleep is a vital factor toward our well-being, but within the last 50 years Americans have reported a 1.5–2 hour reduction in sleep per night. Modern life continuously devalues sleep; our increasingly busy lifestyles are leading to widespread sleep deficiencies. At the same time obesity, diabetes, and other chronic diseases have skyrocketed. Are you one of those people who are always tired? Is your life just too busy to fit in a good night’s sleep?
Here’s an overview of what happens metabolically throughout a good night’s rest. While we sleep, our metabolism, breathing, digestion, heart rate, and movements all decrease so that our energy needs are much lower. In turn, blood sugar levels remain relatively stable throughout the night. If individuals are, on the other hand, kept awake while fasting for about the same time frame, blood sugar levels would fall significantly. Our metabolism reflects our energy requirements while we’re either awake or sleeping; it appears to follow diurnal rhythms. Sleep is a necessity in recovery; when we don’t get enough, our health will ultimately suffer. Research indicates a strong relationship with sleep deprivation and, in addition to cognitive function, chronic diseases.
Shortened sleep can result in weight gain, which can then interfere with sleep; a vicious cycle is created when we miss out. Sleep deprived individuals reportedly have a 35% greater chance of gaining more than 5kg over the course of 6 years. There are so many of us out there who just keep gaining weight year after year. While there’s obviously a number of things causing this weight gain, sleep is likely one of the factors. Lack of sleep (less than 6 hours per night) alters our metabolism in profound ways—the end results are dramatic: insulin resistance, decreased energy, enhanced appetites, and damaged immune systems. What does that mean? Weight gain and chronic disease!
Why would our bodies have a worse glucose tolerance following a restless night? Well, let’s look at this through an evolutionary perspective. Our ancestors would have likely remained awake when there was some kind of threat; in this respect, a heightened glucose availability state would have been an advantage. Appetite stimulation would have resulted in an increased food intake which meant more energy and so on and so forth. Today, what was once advantageous is now clearly detrimental; studies consistently show an increase in BMI with decreased sleep. What’s more? Being overweight (BMI 25kg/m2 and higher) linearly increases our risks for chronic disease and death.
Recent research is linking sleep loss with our immune and inflammatory systems. Whole body, low-level inflammation as well as the activation of our immune system occurs after sleep loss. Furthermore, one night of recovery sleep doesn’t reverse the lack of sleep the previous night; inflammatory and immune cell markers stay elevated. These inflammatory and immune cell markers do a number of things including raising our risks for heart disease and other chronic diseases. If you’re an athlete and have never understood why you can’t fully recover between workouts, sleep may be the answer.
What are some steps you can take to get more sleep? Naps are great! Short naps under 20 minutes will avoid a lot of the grogginess associated with longer naps. When these short naps follow coffee consumption, alertness will be even greater after the nap. Bright lights after a nap are also a good idea to avoid grogginess. Try getting into the habit of going to bed earlier. If you have problems falling asleep, it would be a good idea to avoid brighter lights (e.g. computer) before bedtime. It may be hard at first, but eventually you should be able to break your bad habits and get in more valuable sleeping time.
Sleep is a fundamental requirement for all mammals. Why? That remains a mystery. Whatever the reason, chronic sleep deprivation leads to a slew of health problems including obesity, diabetes, and heart disease. By 2010, an estimated 33% of adult Americans were overweight and 36% were obese! Approximately 8.3% of Americans had diabetes and 35% fit into the pre-diabetic range. Clearly this isn’t just because of lack of sleep but a variety of factors, including exercise and diet; either way, sleep plays its part. No matter how busy you are, make time for a good night’s sleep! Your body will thank you for it!
Faraut B, Boudjeltia K, Vanhammed L, Kerkhofs M.(2012) Immune, inflammatory and cardiovascular consequences of sleep restriction and recovery. Sleep Med Rev 16:137-149.
Kamdar B, Needham D, Collop N.(2012) Sleep Deprivation in Critical Illness Its Role in Physical and Psychological Recovery. J Intensive Care Med 27(2):97-111.
Killick R, Banks S, Liu P.(2012) Implications of Sleep Restriction and Recovery on Metabolic Outcomes. J Clin Endocrinol Metab 97:3876–3890.
Lucassen E, Rother K, Cizza G.(2012) Interacting epidemics? Sleep curtailment, insulin resistance, and obesity. Ann N Y Acad Sci 1264(1):110–134.
See this and other articles on Jennifer Novakovich's website JennovaFoodBlog.com