Sleep Affects Your Diet, and Overall Health, More Than You Think

You may have heard that food can actually influence the quality of your sleep—but new research shows that sleep can also influence when we eat, our metabolism, and our risk of developing cardiovascular related diseases as well.

The National Sleep Foundation recommends those between the ages of 18 and 64 sleep for at least seven hours each night for optimal health and wellbeing, but over one-third of Americans regularly miss that mark. People aren't heading to bed early enough, either, and consequences are much more serious than just being cranky throughout the day.

A new study, published Tuesday in the peer-review Journal of the American College of Cardiology, suggests that sleeping less than six hours per night could greatly increase your risk of cardiovascular disease. The study, which included 4,000 participants at an average age of 46 with no history of heart disease, showed that people who didn't get at least six hours of sleep were 27 percent more likely to develop atherosclerosis (a build up of plaque in arteries).

Researchers came to this conclusion after studying participants' sleep activity for 7 days, taking an ultrasound of the heart and cardiac CT scans, and comparing the data against those who got between 7 and 8 hours of sleep each night.

Furthermore, a recent international review of previously published studies considered the effect of sleep on physical health—the results of that review were published in the Advances in Nutrition journal in December 2018.

Research showed an increased risk of poor health for those who prefer to stay up late, as they tend to entertain more erratic eating patterns and consume unhealthy foods, especially compared to those who get adequate sleep and wake up early.

The review explained researchers used an emerging field in nutritional epidemiology to come to their conclusion. It's known as chrono-nutrition, which encompasses three separate facets of eating behavior: timing, frequency, and regularity to help interpret results.

One’s chronotype, more commonly known as a circadian rhythm, serves as an internal clock, regulating the body’s 24-hour cycle. This internal clock tells you when to sleep and when to wake up—even when to eat. Researchers found people with an evening chronotype, those who would refer to themselves as "night owls," face 2.5 times more risk for health conditions such as heart disease and Type 2 diabetes. Their results were weighed against those than those who get enough sleep and rise early in the morning.

The team behind the study believe this phenomenon has everything to do with diet. Those with an evening chronotype tend to have worse diets than those who go to bed earlier as well as wake up earlier. Night owls tend to consume more caffeine, fat, alcohol, sugar, fast food, and snacks, and also tend to eat fewer whole grains and produce than their early-rising counterparts.

Those who go to sleep later than usual also frequently skip breakfast, leading to larger meals later in the day with excess snacking.

Eating your way through a majority of calories later in the day has been linked to an increased risk for Type 2 diabetes, as circadian rhythms influence how your body metabolizes glucose. The review noted glucose levels should naturally decline throughout the day and reach their lowest point at night. However, since many of those who stay up late consume a great deal of calories after dark, their metabolism can be negatively affected, as the body has to stop following its normal biological process to metabolize food.

Furthermore, evidence showed that those who skimped on sleep often choose to sleep more on weekends, which also has an impact on their diets and metabolism.

The review noted chronotype can be influenced by environment, career, social culture, age, and ethnicity. One study in particular suggested sleep was impacted by how much sunlight they enjoyed that day—every additional hour participants spent outside that day led to 30 minutes of “advance sleep” later that evening.

While chrono-nutrition is still a relatively new field, researchers believe this thorough review of 135 studies suggests that targeting one's sleep patterns could be the next frontier of prevention and treatment for chronic diseases related to diets.