Lipitor is a brand name for atorvastatin, a medication used to lower cholesterol levels in the blood [1]. According to the sources provided, there is no evidence that suggests that Lipitor loses its effectiveness when taken with fatty foods. However, it is essential to note that a high-fat diet can increase cholesterol levels, which may require a higher dose of Lipitor to achieve the desired effect [2].

A cardiologist's take on the keto diet [2] indicates that the keto diet, which is high in fat, may have a positive effect on cholesterol levels in some people. However, the article cautions that the diet may not be suitable for everyone and that patients should consult their doctors before starting the diet.

A study published in the Journal of Clinical Lipidology [3] found that taking atorvastatin with a high-fat meal did not affect the drug's effectiveness in reducing LDL cholesterol levels. However, the study also notes that taking atorvastatin with grapefruit juice, which contains a compound that inhibits the metabolism of the drug, can increase the risk of side effects.

In conclusion, there is no evidence to suggest that Lipitor loses its effectiveness when taken with fatty foods. However, a high-fat diet can increase cholesterol levels, which may require a higher dose of Lipitor to achieve the desired effect. Patients should consult their doctors before starting any diet or making changes to their medication regimen.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.pennmedicine.org/news/news-blog/2019/april/a-cardiologists-take-on-the-keto-diet
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7444011/