Yes, it is true that it is no longer considered necessary to do a blood test to measure cholesterol after the age of 75. This is because there is limited data on the benefits of measuring cholesterol in older individuals, as the mathematical models used to make treatment and risk evaluation recommendations are not very reliable for this age group. While cholesterol can still be harmful, the focus is on promoting healthy lifestyle habits such as staying active, avoiding smoking, consuming fruits and vegetables, avoiding saturated fats, and adopting a Mediterranean diet if possible. Testing is not recommended for individuals over 75 to assess the impact of these measures.