I remember a patient who was fired from his job when his employer found out he had prostate cancer. Life insurance can still be denied if you release medical history info. But neither employers nor life insurance have any recourse if you do not allow them to have that info.
What protects you is the Health Insurance Portability and Accountability Act (HIPAA), a federal law, passed in 1996. The US Government grounded the justification for HIPAA in our 4th Amendment implied right to privacy. It is implied because the Amendment prevents the Government from illegal searches and seizures, which Courts have interpreted since 1967 (Katz v. United States, 389 U.S. 347) implies it. It is applied to the states by the 14th Amendment.
Justice Alito, writing for the majority, said the Court erred in Roe v. Wade in finding there is an implied right to privacy in the Constitution. He claims that the decision only applies to abortion. He points out that there are several cases that were decided based on the implied right to privacy: Loving, 388 U. S. 1 (right to marry a person of a different race), or procreation, Skinner, 316 U. S. 535 (right not to be sterilized); Griswold, 381 U. S. 479 9 (right of married persons to obtain contraceptives); Eisenstadt, 405 U. S. 438 (same, for unmarried persons). Clarence Thomas, in a concurring opinion omits Loving (he is a Black man married to a White woman) but adds to the list Lawrence v. Texas (preventing Gov't intrusion on sex between consenting adults) and Obergefell v. Hodges (allowing gay marriage). He signalled that the 6 to 3 Court is open to hearing cases based on challenges to the right to privacy.
So can an employer (e.g., Walmart), challenge HIPAA because they have an interest in employing only people who have expected longevity enough to justify their investment in training? The Court, applying the same legal theory that there is no implied right to privacy in the medical arena, can overturn HIPAA. My state (California) has an explicit right to privacy in the State Constitution, but not all states do. You may want to talk to your state legislators about this.
Edit 7/24/22- Since all current comments seem to be about abortion, and not about privacy rights, I will ask Darryl to lock this thread when he returns in August. Off-topic comments are filling my inbox and distracting me. - Allen