Researchers found phthalates, a group of chemicals that are used to make plastics soft and are known to disrupt the endocrine system, and other plasticizers in popular fast food items.

Air pollution reduces sperm count in mice by causing inflammation in the brain. The brain has a direct line to the reproductive organs affecting fertility and sperm count under stressful conditions.

Older adults who studied a second language had significant cognitive improvements without becoming fluent, suggesting that you don’t have to be fully bilingual for your brain to benefit. 

Poor sleep is associated with worse cognitive health. The researchers found a U-shaped relationship between sleep and cognitive decline, with the sweet spot being 5.5-7.5 hours of self-reported sleep.