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Why do chylomicrons enter the lymphatic system before reaching the bloodstream?

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Synthesis of palmitate — Fat Palmitic acid is one of the most prevalent fatty acids occurring in the oils and fats of animals; it also occurs naturally in palm oil. It is generated through the addition of an acetyl group to multiple malonyl groups connected by single bonds between carbons. This structure forms a saturated acid—a major component of solid glycerides.

Chylomicrons are large lipoprotein particles, typically ranging from 75 to 600 nm in diameter, that are synthesized in the absorptive cells of the small intestine following the digestion of dietary fat.12

They enter the lymphatic system through specialized lymphatic capillaries known as lacteals because of their significant size. While smaller molecules, such as medium-chain fatty acids, can pass directly into the blood capillaries of the portal circulation, chylomicrons are too large to cross the basement membranes of these blood capillaries. The lacteals, however, possess a structure that allows these large lipid-protein aggregates to enter and be transported through the lymphatic vessels, eventually reaching the bloodstream via the thoracic duct and the subclavian vein.123