A good night of sleep is essential for a person's general health, cognitive functioning, and emotional wellbeing. Studies suggested that intake of omega-3 polyunsaturated fatty acids (omega-3 PUFAs), which include docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), could help with mood and sleep.

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    Eighty-four healthy adults who habitually consumed low amounts of oily fish (25–49 years old) completed a 26-week placebo-controlled, double-blind, randomized trial. The participants were randomly assigned to one of the three treatment groups: the DHA-rich capsules provided 900 mg DHA/day and 270 mg EPA/day, the EPA-rich capsules provided 360 mg DHA/day and 900 mg EPA/day and the placebo capsules contained 1 g refined olive oil (1).

 

    Compared to placebo, improvements in actigraphy sleep efficiency (p = 0.030) and latency (p = 0.026) were observed following the DHA-rich oil supplementation. DHA-rich oil treatment resulted in a longer total sleep time (455.17 ± 6.18 vs 437.91± 7.56 minutes, p= 0.018) than that of the placebo group. A trend towards improved sleep efficiency was identified in the EPA-rich group compared to placebo (p = 0.087). This study demonstrated some positive effects of dietary supplementation with omega-3 PUFAs in healthy adult normal sleepers (1).

 

    Mood swings and sleep problems are common menopausal symptoms. The effects of omega-3 fish oil and soybeans on menopausal symptoms were evaluated in a randomized double-blind, placebo-controlled clinical trial (2). Soybeans have been considered the most reliable source of isoflavones for alleviating the symptoms of menopause.

 

    Postmenopausal women (45–60 years old) were randomly assigned to one of three groups: 500 mg of the powder and extract of soybean; 1000 mg of omega-3 fish oil, 180 mg of EPA, and 120 mg of DHA; or placebo daily for 3 months.

 

    Compared to placebo, both omega-3 fish oil and soybean significantly improved hot flushes, sweating, and sleep problems in the postmenopausal women (p <0.05), as well as the depressive mood (p = 0.004) and anxiety (p = 0.001). There were no differences between the two intervention groups on the effectiveness.  The 12-week daily supplementation of 1 gram omega-3 fish oil could reduce the mean scores on all items of the psychological subscale, and the reduction was significant for the items relating to depression and anxiety and helped to alleviate the sleep problem. Omega-3 fish oil is as effective as soybean for improving mood and sleep during menopause (2).

 

    Omega-3 PUFAs have also been considered promising therapeutic approaches for people who experience depression. The differential effects of EPA and DHA in preventing the cytokines-induced decrease in neurogenesis and increase in apoptosis were demonstrated using cell culture models. When supplemented 22 people with major depression either 3 g of EPA or 1.4 g of DHA daily for 12 weeks, treatment with either omega-3 PUFAs was associated with a significant improvement in depression, with an average 64% drop in symptoms for the EPA group and 71% in the DHA group (3).

 

    Good sleep is also critically important for children's growth and development. Sleep problems are linked with attention-deficit/hyperactivity disorder (ADHD), as well as with other difficulties with behavior and learning in children.

 

    In a large epidemiological sample of healthy children aged 7–9 years (n = 395) from UK schools, associations between blood fatty acid concentrations and subjective Child Sleep Habits Questionnaire were examined. In 40% of the epidemiological sample, Child Sleep Habits Questionnaire scores indicated clinical-level sleep problems. The poorer total sleep disturbance scores were associated weakly but significantly with lower blood DHA and a lower DHA: arachidonic acid ratio (4).

 

    A subset of those children (n = 362) who were underperforming in reading was included in a randomized controlled trial, in which the children were either supplemented with 600 mg algal DHA or placebo daily for 16 weeks. In a randomly selected subsample (n = 43), sleep was also assessed objectively via actigraphy (4).

 

    In the actigraphy group, DHA supplementation led on average to seven fewer wake times and 58 minutes more sleep per night. The higher blood levels of DHA may relate to better child sleep and the objective evidence from actigraphy suggested that DHA supplementation could improve children's sleep (4).

 

    DHA is also highly important during pregnancy for optimal development and functioning of fetal neural tissue. Infant ability to organize sleep and wake states following parturition is highly associated with later developmental outcomes.

 

    The impact of maternal DHA intake on infant sleep patterning was assessed in the first 48 postnatal hours in a longitudinal, randomized, double-blinded, placebo-controlled study. Women (18-35 years of age) with no pregnancy complications consumed a cereal-based functional food (92 kcal) containing 300 mg DHA an average of 5 days/week or placebo bars (n=27 DHA, n=21 Placebo). The intervention began at 24 weeks gestation and continued until delivery (38-40 weeks). Infant sleep/wake states were measured on postnatal days 1 and 2 using a pressure-sensitive mattress recording respiration and body movements (5).

 

    There were significant group differences in arousals in quiet sleep on day 1 (p=0.006) and day 2 (p=0.011) with fewer arousals in the DHA intervention group compared to those of the placebo group. Similarly, arousals in active sleep on day 1 were significantly lower in the DHA-intervention group (p=0.012) compared to the placebo group. The results suggested that increased prenatal supply of dietary DHA has a beneficial impact on infant sleep (5).

 

    The essential fatty acid docosahexaenoic acid (DHA), found in cold-water marine fish, has a central role in regulating the biophysical properties of neural membranes. Based upon animal studies, specific regions of the brain, including the cerebral cortex, synapses, and retinal rod photoreceptors, have a particularly high DHA concentration. Adequate DHA intake is especially important during pregnancy, accumulating in fetal tissue at a particularly high rate during the third trimester (5).

 

    Multiple research groups have investigated infant cognitive function related to maternal DHA supplementation and reported better sleep-state patterning, habituation, attention, problem-solving and visual acuity in infants of mothers consuming DHA supplementation compared to infants of mothers without DHA supplementation. Developmental advantages related to maternal DHA supplementation extend into early childhood with better IQ at 4 years of age and neurological development at 5.5 years of age (5).

 

    EPA and DHA are omega-3 PUFAs mainly found in oily fish. A 3.5 oz (100 g) serving of wild salmon provides from 1 g to 2 g of EPA and DHA. 1 g of fish oil per day would correspond to eating three salmon meals per week. Omega-3 PUFAs, are typically low in Western diets. Increase fatty fish intake can be beneficial for improving emotional wellbeing, reducing anxiety, stress, and depression and helping with sleep quality as shown in the studies mentioned from newborns to menopausal women.

 

References:

1. Patan, M. J., Kennedy, D. O., Husberg, C., Hustvedt, S. O., Calder, P. C., Middleton, B., … Jackson, P. A. (2021). Differential Effects of DHA- and EPA-Rich Oils on Sleep in Healthy Young Adults: A Randomized Controlled Trial. Nutrients, 13(1), 248.

2. Purzand, B., Rokhgireh, S., Shabani Zanjani, M., Eshraghi, N., Mohamadianamiri, M., Esmailzadeh, A., … Allahqoli, L. (2020). The comparison of the effect of soybean and fish oil on supplementation on menopausal symptoms in postmenopausal women: A randomized, double-blind, placebo-controlled trial. Complementary Therapies in Clinical Practice, 41, 101239.

3. Borsini, A.,et. al. (2021). Omega-3 polyunsaturated fatty acids protect against inflammation through production of LOX and CYP450 lipid mediators: relevance for major depression and for human hippocampal neurogenesis. Molecular Psychiatry.

4. Montgomery, P. et. al. (2014). Fatty acids and sleep in UK children: subjective and pilot objective sleep results from the DOLAB study - a randomized controlled trial. Journal of Sleep Research, 23(4), 364–388.

5. Judge, M. P., Cong, X., Harel, O., Courville, A. B., & Lammi-Keefe, C. J. (2012). Maternal consumption of a DHA-containing functional food benefits infant sleep patterning: An early neurodevelopmental measure. Early Human Development, 88(7), 531–537.