Scientific Review on Palmitic Acid, its Physiological Role, Metabolism and Nutritional Implications

Posted on: November 21, 2017

In the recent review published in Frontiers in Physiology, the authors brought some light on the crucial role that palmitic acid plays in human health. Despite being negatively depicted as 'unhealthy' for its association to palm oil, particularly rich in palmitic acid, the authors reported how human evolution gave to this compound a central place in human physiology.

Palmitic acid is the most abundant saturated fatty acid in the human body and on average a 70kg person is made up of 3.5kg palmitic acid.  An internal 'control mechanism' (de novo lipogenesis) makes sure that its concentration is kept balanced by internally synthesizing palmitic acid from other fatty acids, sugars and proteins. In other words, changes in palmitic acid intake from the diet do not influence the amount of palmitic acid present in the body. Only when the 'control mechanism' is disrupted due to e.g. excessive intake of energy and sugars and sedentary lifestyle, health issues arise.  

The authors further explained the variety of pathways in which palmitic acid is involved, justifying the impressive abundance of palmitic acid in humans and its physiological relevance. For instance, palmitic acid has a critical role in cellular membrane functionality by affecting their 'flexibility' and permeability and it forms reversible links to cell membrane proteins, thus being involved in regulating the 'traffic' of molecules in and out of cells and inter cells 'communication'. Palmitic acid is then the precursor of PEA, a compound produced by our body with neuroprotective, anti-inflammatory and analgesic activities. Palmitic acid is also a component of the pulmonary surfactant, a 'lubricant' essential during breathing and produced by the lungs to protect them from injuries and infections.

Finally yet importantly, the authors dedicated part of the publication investigating the alleged correlation between cancer and an excess dietary palmitic acid intake. In this context, the authors concluded that the imbalance among different fatty acids, mainly SAFA and PUFA, rather than a single fatty acid, might play a role in generating a cellular environment that favors carcinogenesis. Following the authors conclusions, this might also be true in the context of the controversial association of saturated fatty acids intake and increased cardiovascular disease risk. For the authors the imbalance intake of PUFA, rather than the absolute intake of SAFA and palmitic acid, may be key in explaining the detrimental health effects attributed to excessive SAFA and palmitic acid intake.