Vague federal directives have led to frantic action, and perhaps overreaction, before a Friday deadline.

Robert F. Kennedy Jr., the nominee to lead the Department of Health and Human Services, made disputed claims before the Senate Committee on Health, Education, Labor and Pensions.

In a Senate hearing, Robert F. Kennedy, Jr. said that efforts to address the high rates of chronic disease need to start with fixing the food supply.

Health hazards from soot and smoke blown indoors onto furniture and walls can linger for months, researchers say: “Wind will get through every crack.”

After developing chronic pain, I started looking into what scientists do — and still don’t — understand about the disease. Here is what I learned.

As many as two billion people suffer from it — including me. Can science finally bring us relief?

But the report, on the experiences of 13 patients, found that the drug had no benefit for some people and that some who benefited said the improvement didn’t last.

While some agree with Robert F. Kennedy Jr. that the agency needs reform, their ideas for fixing it are very different from his.