When you think of lifestyle changes, you may mostly think of eating healthy and exercising, but not the amount of sleep you get every night. However, there is some evidence suggesting that the amount of quality shut-eye you get at night could contribute to causing high lipid levels. While getting too little sleep may have a negative impact on your cholesterol levels, so can getting too much sleep.
How Does Sleep Affect Your Lipids?Although there are not a lot of studies that have examined this connection, most suggest that the relationship between sleep and high lipid levels follows a U-shaped curve. That is, consistently getting less than six hours of sleep per night may affect your cholesterol and triglyceride levels in the same manner as sleeping more than eight hours every night. This pattern has also been linked to other health conditions, such as type 2 diabetes, high blood pressure, heart disease and certain respiratory diseases.
The effect sleep has on lipids highly varies and appears to affect genders differently. In some studies, no significant difference between sleep and lipid profiles were noted, while other studies revealed that too little or too much sleep affected HDL, LDL and/or triglycerides.
For women, HDL and triglyceride levels appeared to be more affected by sleep duration than men in some studies. In some of these cases, HDL was lowered by up to 6 mg/dL and triglyceride levels were increased by up to 30 mg/dL in women who slept less than six hours or more than eight hours. In most of the studies conducted to date, LDL did not appear to be significantly affected by sleep patterns.
Sleep patterns appeared to have a different effect on men. Some studies suggested that LDL increased by up to 9 mg/dL in men who slept less than six hours. In most of these studies, triglycerides and HDL cholesterol did not appear to be significantly affected.
One study also revealed that getting too much sleep (greater than eight hours) or too little sleep placed individuals at higher risk of metabolic syndrome, which is a constellation of signs and symptoms that include lowered HDL, raised triglyceride levels, obesity and elevated blood pressure and glucose levels.
Why Could Sleep Adversely Affect Your Lipids?
Although there appears to be a relationship between sleep and high lipid levels, there are some factors that could contribute to high cholesterol in these studies, too. In some of these studies, it was also discovered that individuals sleeping less per night (less than six hours) also had poorer lifestyle habits, such as experiencing a higher level of stress on their jobs, skipping meals or eating out at least once per day, not exercising and were more likely to smoke – all of which could contribute to increasing cholesterol and triglyceride levels, as well as increasing the risk of developing heart disease.
Additionally, reduced sleep is thought to modify such hormones as leptin and ghrelin, both of which might help increase appetite and food intake – and obesity. It is also thought that less sleep might increase levels of cortisol, which could cause inflammation that contributes to heart disease.
The connection between high lipid levels and sleep that exceeds eight hours is not fully known.
While there is accumulating evidence suggesting a possible link between high lipids and getting too much or too little sleep, more studies are needed to establish a definitive link. Because adverse sleep patterns have also shown to play a role in causing heart disease and chronic conditions, getting the appropriate amount of sleep is an important part of following a healthy lifestyle.
Kaneita Y, Uchiyama M, Yoshiike N, et al. Associations of usual sleep duration with serum lipid and lipoprotein levels. Sleep 2008;31:645-652.
Dochi M, Suwazono Y, Sakata K, et al. Shift work is a risk factor for increased total cholesterol level: a 14 year prospective cohort study in 6886 male workers. Occup Environ Med 2009;66:592-597.
Amagai Y, Ishikawa S, Gotoh T, et al. Sleep duration and incidence of cardiovascular events in a Japanese population: the Jichi Medical School cohort study. J Epidemiol 2010;20:106-110.
Hall MH, Muldoon MF, Jennings JR, et al. Self-reported sleep duration is associated with the metabolic syndrome in midlife adults. Sleep 2008;31:635-643.
Cappuccio FP, Cooper D, D’Elia L et al. Sleep duration predicts cardiovascular outcomes: a systemic review and meta-analysis of prospective studies. Eur Heart J 2011;32:1484-1492.
Mosca M, Aggarwal B. Sleep duration, snoring habits, and cardiovascular disease risk factors in an ethnically diverse population. J Cardiovasc Nurs 2011 (online)