The 39-year-old activist and Good Place actress called out the 43-year-old tennis legend, and explained why she felt "uncomfortable" about the promotion of the medicine.
"Serena Williams is selling GLP-1s," she began. "The thing I feel most uncomfortable about here is that celebrities have access to doctors most other don't have access to. These 'miracle' weight loss drugs come at a price."
"The side effects can include paralysis of the gastric system, pancreatitis, cancer, hair loss, osteoporosis, severe malnutrition, muscle mass loss, depression (there have been reports of suicide), thyroid issues, blindness and they can really wreak havoc on your metabolism," she continued.
"If things go wrong, you don't have a billion dollars to fix it, that's why I don't like celebrities pushing drugs with such drastic documented side effects."
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"I GOT THIS INFORMATION FROM THE WEBSITES OF THE DRUGS IN THE SIDE EFFECTS PAGES. You can go see for yourself," she went on to clarify in the caption.
"Go ahead and take the drug or anything you like... Please just make sure you have access to proper healthcare before you make the decision to take any drug that has drastic results. Things can go south very fast, as is documented in many lawsuits emerging regarding these medicines. They can be amazing for some, but also devastating for others. So make sure you're prepared incase you are one of the unlucky ones. That is all I ask. ❤️," she went on to say before adding more clarifications, including addressing Serena's husband Alexis Ohanian, who is confirmed to be an investor in Ro, the direct-to-patient healthcare company Serena promoted in People's article.
"Ps. Many people have asked me to highlight the fact that Serena's husband is an investor in this company. Another reason we should take every celebrity endorsement with a pinch of salt."
"PPS. This post is about transparency, not judging Serena's body. Nor is it judging you or your decision to take a GLP-1. It's a literal, FACTUAL, evidence based, plea to make sure you have adequate medical support if you DO take these drugs. They're for the long term and we should always be prepared for anything that can significantly change our bodily functions for the better or worse! If you have a problem with my call for transparency and medical responsibility, you are the problem. My size does not change the fact that we need to maintain transparency, especially when celebrities make millions from endorsing a drug," she added, before concluding: "PPS. Cancer is not a direct side effect but a risk for anyone with a predisposition towards thyroid cancer. Which sadly many doctors forget to ask when they give out these drugs."