FDA proposes mandatory notice for food additives; Biden cancer update; pulse oximeter tunes itself to skin tone — Morning Medical Update

FDA proposes mandatory notice for food additives

The proposed rule would end a decades-old practice that let companies declare new ingredients safe without telling the agency.

The U.S. Food and Drug Administration (FDA) issued a proposed rule Monday that would require food manufacturers to notify the agency when they determine an ingredient is "Generally Recognized as Safe," or GRAS, according to the Department of Health and Human Services (HHS).

Since 1958, companies have been permitted to self-affirm that ingredients are safe without a full government review; the FDA encourages notification of new GRAS ingredients but does not require it. The proposal would make that notice mandatory and expand a public inventory of the filings.

Acting FDA Commissioner Kyle Diamantas told reporters that shifting to a mandatory system "closes a decades-old information gap," and said the rule is intended to increase transparency and consumer confidence in the food supply.

The FDA cast the change as part of the Trump administration's "Make America Healthy Again" initiative.

HHS and the U.S. Department of Agriculture have submitted a proposed definition of ultra-processed food for final review, with details to come later, and Diamantas said the FDA planned to issue guidance Tuesday on limiting biological hazards for processors of fresh-cut produce, as ongoing salmonella and cyclosporiasis outbreaks have sickened thousands of people in the U.S.

Biden's prostate cancer has spread, son says

Hunter Biden told the BBC that the 83-year-old's disease has metastasized further and is causing considerable pain.

Former President Joe Biden's prostate cancer has spread further and is causing him significant pain, his son Hunter Biden said in an interview with the BBC broadcast Friday.

"The cancer has spread, metastasized into his bones and further," he said. "It's very painful and it's very debilitating in many respects." He said his father continues to appear publicly and speak on issues he cares about. A spokesman for the former president declined to comment Saturday.

Biden, 83, disclosed in May 2025, less than four months after leaving office, that he had been diagnosed with an aggressive form of prostate cancer that had already spread to bone. His office said at the time that the diagnosis followed a small nodule found during a routine physical exam. A spokesman said in October that he was undergoing radiation and hormone therapy. Prostate cancer is the most commonly diagnosed cancer and the second-leading cause of cancer death among men in the U.S., according to the National Institutes of Health.

Pulse oximeter tunes itself to skin tone

A wrist-worn Tufts device measured oxygen saturation within 2.87% of a reference oximeter, with no observable bias by skin tone.

A wrist-worn sensor that calibrates itself to a patient's skin reflectance measured blood oxygen saturation accurately across a range of skin tones, according to a study published in Review of Scientific Instruments. The device, called ChromaSense, reads light reflected from tissue at the wrist rather than light transmitted through a fingertip, and it profiles a person's skin reflectance before adjusting both the light it emits and the signal processing it applies. Melanin absorbs and scatters light, which in patients with darker skin can weaken the signal or distort the ratio used to calculate oxygen saturation.

A 2020 New England Journal of Medicine analysis found occult hypoxemia went undetected in as many as 17% of Black patients, about three times the rate in white patients.

Testing at the Hypoxia Research Laboratory at the University of California, San Francisco, briefly lowered oxygen across a 70% to 100% saturation range in healthy adult volunteers of varied skin tones and compared the readings against an oximeter that samples blood directly. ChromaSense came within 2.87% of the reference and showed no observable tone-dependent bias, including at lower saturations, meeting FDA performance requirements. Participants were healthy volunteers under induced hypoxia rather than patients in clinical care, and the device is not commercially available.