Oral Fat Tolerance Test (OFTT) in Human
Francine dos Santos-Macedo, Dilliane da Paixão Rodrigues Almeida, Bianca Martins Gregório, Fernanda Amorim de Morais Nascimento Braga, Caroline Fernandes-Santos
Disclaimer
The authors declare that there are no conflicts of interest associated with this research study.
Abstract
Following the consumption of a standardized high-fat meal, the oral fat tolerance test (OFTT) assesses the postprandial lipemic (PPL) response of blood triglycerides (TG). Blood samples are obtained four hours after meal ingestion, with a targeted TG level of ≤ 220 mg/dL considered within the normal range. An altered PPL response is defined by TG levels exceeding 220 mg/dL. The PPL is influenced by various factors, such as the quality and type of foods ingested in the diet, physical exercise, body metabolism, and genetics. The PPL response may predict the development of Atherosclerotic Cardiovascular Disease, thus serving as an early marker of the atherosclerotic process associated with metabolic disorders.
Before start
Depending on the blender available, preparing the volume of 4 meals at once is more practical because there are losses on the blender's wall. Participants must fast for 8 to 10 hours before blood collection. They should avoid consuming fatty foods and engaging in physical activity in the 72 hours before the test.
Steps
OFTT meal preparation (milkshake)
Identify the cup with the participant's name.
Weigh the empty cup and record it (W1).
Weight the ingredients
Add the ingredients to the blender and mix.
Distribute the milkshake into plastic cups.
Weigh the whole cup and record it (W2).
Place the lid and straw.
Oral Fat Tolerance Test (OFTT)
Collect venous blood from the arm using a 5 mL syringe and reserve it in a serum separator tube.
Offer the test meal to the study participant.
Monitor the time it takes for the participant to consume the milkshake. They should consume as much as possible.
After consumption is complete, weigh the cup (W3).
Collect a new venous blood sample from the arm 4 hours after the start of meal ingestion.
Calculating milkshake intake
Apply the following formula:
Serum triglyceride assay
Centrifuge the blood at 2,000 x g for 10 minutes.
Transfer the serum to 2.0 mL microtubes.
Conduct the biochemical assay following the manufacturer's instructions.
