Improving Your Sleep May Be Key for Preventing and Treating Metabolic Disorders

By Dr. Mercola

A majority of Americans are not getting enough sleep, and modern technology is in large part to blame. According to the 2014 Sleep in America Poll,¹ 53 percent of respondents who turn electronics off while sleeping rate their sleep as excellent, compared to just 27 percent of those who leave their devices on.

Even children are becoming sleep deprived. The poll shows that 58 percent of teens aged 15-17 get only seven hours of sleep or less per night. Between 7 and 8 hours may be optimal for the average adult, but children are known to need more sleep than adults.
If your child is overweight and/or exhausted much of the time, chances are high that poor sleep patterns—perhaps resulting from too many light-emitting gadgets—are at play.

The exposure to excessive amounts of light at night, courtesy of electric light bulbs and electronic gadgets of all kinds, makes it exceedingly difficult for your body and brain to wind down for sleep. And this lack of sleep, in turn, can have far ranging health consequences, regardless of your age.

Poor Sleep Worsens Metabolic Disorders

According to recent research^{2, 3} poor sleep could have a significant bearing on metabolic disorders such as obesity, hypertension, and type 2 diabetes. The authors suggest that addressing your sleeping habits may be key for both the prevention and treatment of these disorders. As reported by Medical News Today:⁴

"The reason why metabolic disorders are so influenced by sleep patterns seems to be due to sleep influencing the body's ability to control food intake, metabolize glucose and maintain energy balance.

The new study reviews this existing evidence and makes recommendations for new targets and strategies in the prevention and treatment of these sleep-related forms of metabolic disease.

Among the findings, the review found that disruption of the body's natural sleep cycle—as experienced by shift workers—has a pronounced link with suffering metabolic health, as well as rates of chronic illness and early death."

These authors also blame our declining sleep hygiene on the use of electronic devices such as tablets, portable video games, TVs, and smart phones in the evening.

Another study published in the International Journal of Obesity⁵ found that infants who sleep less eat more, which places them at increased risk of future obesity and related health problems. Infants who, at the age of 16 months, slept less than 10 hours per day ate an average of 10 percent more calories than those who slept for at least 13 hours daily. According to Dr. Abi Fisher of the Health Behavior Research Centre at UCL:⁶

"Previous studies in adults and older children have shown that sleep loss causes people to eat more, but in early life parents make most of the decisions about when and how much their children eat, so young children cannot be assumed to show the same patterns.

The key message here is that shorter sleeping children may be prone to consume too many calories. Although more research is needed to understand why this might be, it is something parents should be made aware of."

To Successfully Lose Weight, You May Need to Sleep More

A number of studies have linked poor sleep and/or sleep deprivation with a higher risk of obesity and difficulty in losing weight. A recent article by Timesleader.com⁷ also discusses the findings from a University of Chicago study, which found that people who slept well lost more fat when dieting, while sleep deprived participants lost more muscle.

On average, both groups lost about the same amount of weight, but clearly, losing fat rather than muscle is definitely to be preferred! The article also notes that:

"[O]ne study found that those who slept five hours per night were 73 percent more likely to become obese than those who spent nine hours with their favorite pillow – I'll repeat: 73 percent!

The reason for this hasn't been pinpointed yet, but some say that lack of sleep lowers the levels of the hormone leptin, which reduces hunger. There's another link between sleep deprivation and weight: diabetes.

The underlying problem with type 2 diabetes is insulin resistance, in which the body does not make proper use of this sugar-processing hormone. And go figure, when you're sleep deprived, your body almost immediately develops conditions that resemble diabetes.

A study of people in their late 20s and early 30s who slept fewer than six and a half hours per night showed they essentially had the insulin sensitivity of someone over 60."

The Persistent Link Between Poor Sleep and Insulin Resistance

Impaired insulin sensitivity, also known as insulin resistance, occurs when your body cannot use insulin properly, allowing your blood sugar levels to get too high. The same applies to leptin, the hormone that tells your brain there is no need for more food. Both insulin and leptin resistance are precursors to type 2 diabetes.

They're also risk factors in many other chronic diseases. In fact, controlling your insulin/leptin levels is one of the most powerful ways to reduce your risk of chronic diseases, including high blood pressure, heart disease, and cancer.

The increase in insulin-related diseases we're now seeing is largely due to lack of exercise combined with the excessive consumption of refined fructose and processed carbohydrates… but it also appears that lack of sleep plays an important part in the equation.

Besides deteriorating your insulin and leptin sensitivity, sleep deprivation also increases levels of ghrelin, a hormone that triggers hunger.⁸ This too can easily result in overeating and/or indulging in the wrong foods. Too little sleep also impacts your levels of thyroid and stress hormones, which in turn can affect your memory, immune system, heart and metabolism, and much more.

By altering the balance of all of these various hormones, lack of sleep can lead to a wide array of health problems, from accelerated aging and earlier onset of Alzheimer's,⁹ to depression, and increased risk for cancer. In fact, tumors have been shown to grow two to three times faster in laboratory animals with severe sleep dysfunctions.

To Sleep Better, Skip the Drugs and Treat Yourself to Bright Daylight During the Day

If you or your child has trouble sleeping, how can you most effectively reverse that trend? For starters, please do NOT make the mistake of turning to sleeping pills—prescription or otherwise. Unfortunately, this is what many end up doing. According to one 2007 study, more than 80 percent of children's doctor visits for sleep problems included a prescription for a sleep drug! Most prescribed for kids' sleep troubles were antihistamines, blood pressure drugs, benzodiazepines, antidepressants, and sleeping pills like Ambien and Sonata.

You certainly do not need to go to medical school to understand that using drugs to help kids sleep is not their best option, as it in no way, shape or form addresses the underlying cause of poor sleep patterns and instead exposes kids to potentially serious medication side effects. The same goes for adults. Instead, I strongly recommend addressing truly foundational issues—such as maintaining a natural rhythm of exposure to sunlight during the day and darkness at night—first. In a recent interview, researcher Dan Pardi revealed why this is so critical for sleep and overall health.

                    Download Interview Transcript

Unfortunately, most people in Western societies spend the larger portion of each day indoors, which essentially puts you in a state of "light deficiency." Meanwhile, most people expose themselves to too much light in the evening, at a time when the natural rhythm calls for light to fade. Research shows that exposure to bright room light before bedtime suppresses melatonin production in 99 percent of individuals. This can effectively rob you of sleep by masking sleepiness, as this hormone influences what time of day or night your body thinks it is—regardless of what time the clock displays.

To correct the situation and return your body to a normal rhythm of waking and sleeping, Pardi recommends getting at least 30-60 minutes of bright outdoor light exposure during daylight hours. This will help "anchor" your biological rhythm. Then, in the evening, you'll want to dim environmental lights and avoid the blue light wavelength to prevent the suppression of melatonin, as this will make it difficult to fall asleep. To do this, you can use blue-blocking light bulbs, dim your lights with dimmer switches and turn off unneeded lights, and if using a computer, install blue light-blocking software like f.lux¹⁰ (Also keep in mind that digital alarm clocks with blue light displays could have a detrimental effect.)

Sleeping Well Is Part of a Healthy Lifestyle Plan

There's compelling research indicating that sleeping too little may increase your insulin and leptin resistance, thereby raising your risk of obesity, diabetes, and other metabolic diseases. To address your sleep problems, I recommend beginning by realigning your circadian rhythms to the natural rhythm of daylight and nightfall.

Without this synchronization, aspects of your waking/sleeping system will be working at the wrong time, making it difficult to sleep at night, while increasing daytime sleepiness. Again, the three factors to keep in mind are as follows:

• Get daylight exposure, ideally around solar noon, for at least half an hour or more each day
• In the evening, dim environmental lights and avoid the blue light wavelength
• When it's time to go to sleep, make sure your bedroom is dark. I recommend installing blackout shades for this purpose, or use a sleep mask to avoid disrupting your melatonin production 

Besides maintaining a natural circadian rhythm, there are a number of additional ways to help improve your sleep if you're still having trouble. For a comprehensive sleep guide, please see my article "33 Secrets to a Good Night's Sleep." Here are 10 often-overlooked factors that might be interfering with your sleep. My previous interview with Dr. Rubin Naiman also delves into some of the most common causes of insomnia, and how to address them.