Smoking or eating leafy greens could be hurting your eyes

Embargoed until: Publicly released:

Exposure to the heavy metal cadmium could reduce your ability to see contrast, especially in low light, fog, or glare, according to US researchers. The team conducted a study of almost 2,000 people and found that those who were exposed to cadmium had weaker eyesight when it came to viewing an image against a background – known as contrast sensitivity. Cadmium is commonly found in cigarette smoke, but can also be found in leafy green vegetables, rice, and shellfish. This study was observational, therefore cannot show cause and effect.

Journal/conference: JAMA Ophthalmology

DOI: 10.1001/jamaophthalmol.2018.3931

Organisation/s: University of Wisconsin-Madison, USA

Media Release

From: JAMA

Is Exposure to Lead, Cadmium Associated With Reduced Ability to See Contrast?

Association of Cadmium and Lead Exposure With the Incidence of Contrast Sensitivity Impairment Among Middle-aged Adults

Bottom Line: Contrast sensitivity is a measure of how well someone sees an image against a background. Diminished contrast sensitivity can impact daily life because common low-contrast conditions include low light, fog or glare. Understanding what might contribute to a decrease in contrast sensitivity is important. An observational study of nearly 2,000 people taking part in an ongoing study of aging examined whether exposure to the heavy metals cadmium and lead was associated with increased risk of impaired contrast sensitivity. Results of the study suggest cadmium exposure, but not lead, was among the factors associated with increased risk. Cadmium exposure typically happens through inhaling cigarette smoke and eating green leafy vegetables, rice and shellfish. Limitations of the study include that no definitive conclusions can be drawn and that the association could be due to another element of cigarette smoking.

News for:


Media contact details for this story are only visible to registered journalists.