Could medical marijuana laws actually be increasing opioid overdose deaths? Are the benefits of medical cannabis worth the possible side effects? Is the blue light in LED lighting damaging our retinas and disturbing our sleep rhythms?


A new study has challenged whether legalizing medical marijuana actually helps prevent opioid-related deaths.

Researchers repeated an earlier analysis that linked medical marijuana laws to slower-than-expected increases in state prescription opioid death rates from 1999-2010. The original authors speculated that patients might be substituting marijuana for painkillers, but they warned against jumping to conclusions.

When the new researchers included data through 2017, they found that states passing medical marijuana laws actually saw a 23 percent higher-than-expected rate of deaths involving prescription opioids. The study determined that any beneficial link between opioid overdose and medical marijuana use was likely coincidental all along.

“We don’t think it’s reasonable to say it was saving lives before, but it’s killing people now,” said researcher Chelsea Shover of Stanford University School of Medicine.

The new study undermines recent policy changes in states including New Mexico, New York, New Jersey and Pennsylvania approving marijuana for patients with opioid addiction.

However, marijuana has been shown to help ease chronic pain, and other studies have suggested medical marijuana laws may reduce opioid prescribing.



The number of medical marijuana cardholders more than tripled in the last five years as more states jumped on the bandwagon, with an estimated 2.6 million Americans using marijuana for their health, according to an Associated Press analysis.

States that expanded the use of medical marijuana for common ailments such as severe pain, post-traumatic stress disorder and anxiety saw a boost in enrollment.

Besides chronic pain, there’s strong evidence marijuana or its ingredients can ease nausea and vomiting from chemotherapy and help with symptoms of multiple sclerosis. Pharmaceutical companies are seeking approval for CBD drugs to treat seizure disorders and autism, and prescription drugs already on the market use synthetic THC to treat weight loss, nausea and vomiting in patients with AIDS or cancer.

While evidence suggests medical marijuana is not effective in treating opioid addiction, it may be helpful in reducing use of opioid painkillers. The National Center for Complementary and Integrative Health, better known for its research on herbs and yoga, has set aside $3 million for studies to determine which of marijuana’s 400-plus chemicals help with pain. THC was excluded due to its mood-altering effects and potential for addiction and abuse.

Despite online claims that marijuana’s ingredients might one day be used to treat cancer, results thus far have been mixed. In fact, one study found evidence that marijuana might interfere with some cancer drugs, making them less effective. However, many cancer patients taking medical marijuana have reported improvements in vomiting, pain, disturbed sleep, anxiety and depression with few side effects.

While medical marijuana does seem to help some patients, “so much is unknown about the risks, side effects and drug interactions,” noted one researcher, Dr. Dylan Zylla of the health care system HealthPartners.

Source: Some Claims of Medical Cannabis Lack Scientific Evidence


Market penetration of LED lighting is increasing, and the U.S. Department of Energy estimates it will represent 48 percent of total lumen-hour sales by 2020 and 84 percent by 2030. While the increased use of LED is positive in terms of energy consumption, the blue light in LED lighting can damage the eye’s retina while disturbing our biological and sleep rhythms, warns a new report.

Scientific evidence confirms the “phototoxic effects” of short-term exposure to high-intensity blue light, as well as an increased risk of age-related macular degeneration after chronic exposure to lower-intensity sources, according to the French Agency for Food, Environmental and Occupational Health & Safety, known as ANSES.

Yet protection from the harmful effects to the retina offered by “anti-blue light” screens, filters and sunglasses varies, and their ability to preserve sleep rhythms is not proven.

ANSES differentiates types of blue light in its report. While “warm white” domestic LED lighting has weak phototoxicity risks, similar to traditional lighting, other LED lighting sources, including the newest flashlights, car headlights and some toys, produce a whiter and “colder” blue light that is more harmful.

Children and teenagers, whose eyes do not fully filter blue light, are particularly sensitive to the harms of cold blue light, the French authority noted. The agency also recommended that only low-risk LED devices be available to consumers and the luminosity of car headlights be reduced.

A separate American study found that blue light can indeed damage the eyes, but only if the wavelengths are below 455 nanometers and the intensity is quite high.

“There are blue light photoreceptors in the retina that directly communicate with the brain circadian clock,” lead author Gianluca Tosini, professor and chief scientific research officer at Atlanta’s Morehouse School of Medicine, wrote in an email. “It is true that exposure to light in the evening affects sleep and circadian rhythms mostly by inhibiting the synthesis of the sleep promoting hormone melatonin.”

But he also said that a few studies have shown that “exposure to blue light in the middle of the day may have beneficial effects” since it increases alertness.

Source: LED lights damage eyes and disturb sleep, European health authority warns

(Risks Alerts are reported by CM Editor Kimberly Tallon)