Health and Light

Light pollution is a threat to human health, the health of ecosystems, and esthetics.  There is a growing body of studies showing that

we are both overexposed to light at night, and underexposed to natural light during the day.

Light exposure affects our moods, hormones, fertility, and immune system. Excessive night light exposure is associated with increased breast cancers.

Earth Hour is March 24, 2018, 8:30-9:30PM local time. Turn off your lights.

The 12 Elixirs – chapter 21 – the fourth elixir: Sleep –

maintain a totally dark bedroom!

Get outdoors during the day!!!

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Increase in Artificial Night Sky Brightness in North America


Temporal organization of physiology is critical for human health. In the past, humans experienced predictable periods of daily light and dark driven by the solar day, which allowed for entrainment of intrinsic circadian rhythms to the environmental light–dark cycles. Since the adoption of electric light, however, pervasive exposure to nighttime lighting has blurred the boundaries of day and night, making it more difficult to synchronize biological processes. Many systems are under circadian control, including sleep–wake behavior, hormone secretion, cellular function and gene expression. Circadian disruption by nighttime light perturbs those processes and is associated with increasing incidence of certain cancers, metabolic dysfunction and mood disorders. This review focuses on the role of artificial light at night in mood regulation, including mechanisms through which aberrant light exposure affects the brain. Converging evidence suggests that circadian disruption alters the function of brain regions involved in emotion and mood regulation. This occurs through direct neural input from the clock or indirect effects, including altered neuroplasticity, neurotransmission and clock gene expression. Recently, the aberrant light exposure has been recognized for its health effects. This review summarizes the evidence linking aberrant light exposure to mood.

Transl Psychiatry. 2017 Jan; 7(1): e1017.
Published online 2017 Jan 31. doi:  10.1038/tp.2016.262
Clin Endocrinol (Oxf). 1998 Jan;48(1):73-9.

Autism and the Mother’s Nutrition

A recent study demonstrated that mothers who took supplements during pregnancy had a lower number of children with autism than mothers who did not take supplements. The study suggests that (!!!) the nutritional state of the mother during pregnancy may have a significant impact on the health of her child.

See chapters 11-14 of The 12 Elixirs for more information on nutrition and the health of our children.

“An international collaboration led by the Department of Epidemiology and Biostatistics at the Drexel University (Philadelphia, USA) set out to investigate the association between mothers’ use of supplementation during pregnancy and risk of ASD in their offspring who were aged 4 to 15 years.
They analyzed data from the Stockholm Youth Cohort, which included 273,107 mother-child pairs living in Stockholm County (Sweden). Mother’s use of multivitamin, iron, and folic supplementation was reported at the first antenatal visit. Diagnosis of ASD with and without intellectual disability in children was obtained from register data.
The researchers found that the prevalence of offspring ASD with intellectual disability was 0.26% and 0.48% in the maternal multivitamin use group and the non-use group, respectively. This meant that mothers who used multivitamin (with or without additional iron or folic acid, or both) was associated with an average 31% lower risk of ASD in children compared with mothers who did not use supplements. After adjusting for potential confounders and using other analytic methods, similar estimates were found.
However, the association study does not prove that multivitamin use caused lower risk of developing ASD in child. Due to limitations of the data, the study cannot answer how type, timing, and dose of supplement influences the ASD risk. Also, it remains to be determined whether there is a critical window for multivitamin use by mother and whether certain combinations of specific nutrients are responsible for the prevention of ASD.
The study results were published in the journal BMJ (October 2017).
Why is this Clinically Relevant?
  • Maternal nutrition during pregnancy is essential for the wellbeing of offspring. This study indicates it is also associated with lower risk of ASD
  • Clinicians may recommend multivitamin supplement for women who plan to become pregnant or are in early pregnancy
  • It is important to select supplements that are manufactured according to GMP which ensures quality standard


[1] DeVilbiss, E.A., et al., Antenatal nutritional supplementation and autism spectrum disorders in the Stockholm youth cohort: population based cohort study. BMJ, 2017. 359: p. j4273.”
Thank you to Carl  at NutriDyn for this reference.