Yes—nutrition supplements changed some nutrients in breast milk, but others stayed stable. The report describes research on mothers’ nutrition and their milk. Selenium was among the nutrients that responded to supplements. B vitamins and the mix of certain milk fats also changed. The key finding was selective change, not a shift in everything measured. The supplied excerpt does not say how many mothers were studied. It also leaves out supplement doses, study length, and the size of the changes. It does not say whether milk Selenium levels rose or fell. That means we cannot put a number on the effect. We also cannot tell whether Selenium alone caused it. The lead researcher’s takeaway was that milk does not simply mirror food intake. The body controls what goes into milk. Some parts respond to added nutrients, while others remain steady. A change in milk content is not, by itself, proof of better health. This excerpt does not establish a benefit for mothers or babies from taking Selenium. For BioSocial members, this is a useful reason to keep tracking specific. A supplement log records what you took. Bloodwork records what was measured in your blood. This report concerns milk, so those results should not be treated as interchangeable. When comparing notes, dose, dates, and the type of test help give numbers context. Shared experiences can raise useful questions without proving that a supplement caused a change. What have you learned from tracking your supplement use and test results during breastfeeding?